Merge remote-tracking branch 'px4/ekf_home_init' into navigator_cleanup_ekf_home_init

Conflicts:
	src/modules/commander/commander.cpp
	src/modules/mc_pos_control/mc_pos_control_main.cpp
	src/modules/navigator/navigator_main.cpp
	src/modules/uORB/topics/vehicle_global_position.h

42 files changed, 3782 insertions, 4154 deletions

diff --git a/Documentation/rc_mode_switch.odg b/Documentation/rc_mode_switch.odg
index 29d738c39..1ef05458f 100644
--- a/Documentation/rc_mode_switch.odg
+++ b/Documentation/rc_mode_switch.odg
diff --git a/Documentation/rc_mode_switch.pdf b/Documentation/rc_mode_switch.pdf
index 856dd55c5..b1a468d17 100644
--- a/Documentation/rc_mode_switch.pdf
+++ b/Documentation/rc_mode_switch.pdf
diff --git a/ROMFS/px4fmu_common/init.d/rc.fw_apps b/ROMFS/px4fmu_common/init.d/rc.fw_apps
index 429abc5ec..9aca3fc5f 100644
--- a/ROMFS/px4fmu_common/init.d/rc.fw_apps
+++ b/ROMFS/px4fmu_common/init.d/rc.fw_apps
@@ -6,7 +6,7 @@
 #
 # Start the attitude and position estimator
 #
-fw_att_pos_estimator start
+ekf_att_pos_estimator start
 
 #
 # Start attitude controller
diff --git a/ROMFS/px4fmu_common/init.d/rc.mc_apps b/ROMFS/px4fmu_common/init.d/rc.mc_apps
index ed3939757..268eb9bba 100644
--- a/ROMFS/px4fmu_common/init.d/rc.mc_apps
+++ b/ROMFS/px4fmu_common/init.d/rc.mc_apps
@@ -5,6 +5,7 @@
 #
 
 attitude_estimator_ekf start
+#ekf_att_pos_estimator start
 position_estimator_inav start
 
 mc_att_control start
diff --git a/ROMFS/px4fmu_common/init.d/rc.mc_defaults b/ROMFS/px4fmu_common/init.d/rc.mc_defaults
index 4db62607a..c1f9db7d1 100644
--- a/ROMFS/px4fmu_common/init.d/rc.mc_defaults
+++ b/ROMFS/px4fmu_common/init.d/rc.mc_defaults
@@ -35,6 +35,12 @@ then
 	param set MPC_TILT_MAX 1.0
 	param set MPC_LAND_SPEED 1.0
 	param set MPC_LAND_TILT 0.3
+
+	param set PE_VELNE_NOISE 0.5
+	param set PE_VELNE_NOISE 0.7
+	param set PE_POSNE_NOISE 0.5
+	param set PE_POSD_NOISE 1.0
+
 fi
 
 set PWM_RATE 400
diff --git a/makefiles/config_px4fmu-v1_default.mk b/makefiles/config_px4fmu-v1_default.mk
index 532e978d0..1daf8277e 100644
--- a/makefiles/config_px4fmu-v1_default.mk
+++ b/makefiles/config_px4fmu-v1_default.mk
@@ -70,7 +70,7 @@ MODULES		+= modules/gpio_led
 # Estimation modules (EKF/ SO3 / other filters)
 #
 MODULES		+= modules/attitude_estimator_ekf
-MODULES		+= modules/fw_att_pos_estimator
+MODULES		+= modules/ekf_att_pos_estimator
 MODULES		+= modules/position_estimator_inav
 #MODULES		+= examples/flow_position_estimator
 
diff --git a/makefiles/config_px4fmu-v2_default.mk b/makefiles/config_px4fmu-v2_default.mk
index e13421acc..7f0c59515 100644
--- a/makefiles/config_px4fmu-v2_default.mk
+++ b/makefiles/config_px4fmu-v2_default.mk
@@ -79,7 +79,7 @@ MODULES		+= modules/gpio_led
 #
 MODULES		+= modules/attitude_estimator_ekf
 MODULES		+= modules/attitude_estimator_so3
-MODULES		+= modules/fw_att_pos_estimator
+MODULES		+= modules/ekf_att_pos_estimator
 MODULES		+= modules/position_estimator_inav
 MODULES		+= examples/flow_position_estimator
 
diff --git a/src/drivers/frsky_telemetry/frsky_data.c b/src/drivers/frsky_telemetry/frsky_data.c
index cfcf91e3f..57a03bc84 100644
--- a/src/drivers/frsky_telemetry/frsky_data.c
+++ b/src/drivers/frsky_telemetry/frsky_data.c
@@ -225,7 +225,7 @@ void frsky_send_frame2(int uart)
 	float course = 0, lat = 0, lon = 0, speed = 0, alt = 0;
 	char lat_ns = 0, lon_ew = 0;
 	int sec = 0;
-	if (global_pos.global_valid) {
+	if (global_pos.timestamp != 0 && hrt_absolute_time() < global_pos.timestamp + 20000) {
 		time_t time_gps = global_pos.time_gps_usec / 1000000;
 		struct tm *tm_gps = gmtime(&time_gps);
 
diff --git a/src/lib/geo/geo.c b/src/lib/geo/geo.c
index f72dc607c..9a24ff50e 100644
--- a/src/lib/geo/geo.c
+++ b/src/lib/geo/geo.c
@@ -1,9 +1,6 @@
 /****************************************************************************
  *
- *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
- *   Author: Thomas Gubler <thomasgubler@student.ethz.ch>
- *           Julian Oes <joes@student.ethz.ch>
- *           Lorenz Meier <lm@inf.ethz.ch>
+ *   Copyright (C) 2012, 2014 PX4 Development Team. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -42,6 +39,7 @@
  * @author Thomas Gubler <thomasgubler@student.ethz.ch>
  * @author Julian Oes <joes@student.ethz.ch>
  * @author Lorenz Meier <lm@inf.ethz.ch>
+ * @author Anton Babushkin <anton.babushkin@me.com>
  */
 
 #include <geo/geo.h>
@@ -52,124 +50,58 @@
 #include <math.h>
 #include <stdbool.h>
 
+/*
+ * Azimuthal Equidistant Projection
+ * formulas according to: http://mathworld.wolfram.com/AzimuthalEquidistantProjection.html
+ */
 
-/* values for map projection */
-static double phi_1;
-static double sin_phi_1;
-static double cos_phi_1;
-static double lambda_0;
-static double scale;
-
-__EXPORT void map_projection_init(double lat_0, double lon_0) //lat_0, lon_0 are expected to be in correct format: -> 47.1234567 and not 471234567
+__EXPORT void map_projection_init(struct map_projection_reference_s *ref, double lat_0, double lon_0) //lat_0, lon_0 are expected to be in correct format: -> 47.1234567 and not 471234567
 {
-	/* notation and formulas according to: http://mathworld.wolfram.com/AzimuthalEquidistantProjection.html */
-	phi_1 = lat_0 / 180.0 * M_PI;
-	lambda_0 = lon_0 / 180.0 * M_PI;
-
-	sin_phi_1 = sin(phi_1);
-	cos_phi_1 = cos(phi_1);
-
-	/* calculate local scale by using the relation of true distance and the distance on plane */ //TODO: this is a quick solution, there are probably easier ways to determine the scale
-
-	/* 1) calculate true distance d on sphere to a point: http://www.movable-type.co.uk/scripts/latlong.html */
-
-	double lat1 = phi_1;
-	double lon1 = lambda_0;
-
-	double lat2 = phi_1 + 0.5 / 180 * M_PI;
-	double lon2 = lambda_0 + 0.5 / 180 * M_PI;
-	double sin_lat_2 = sin(lat2);
-	double cos_lat_2 = cos(lat2);
-	double d = acos(sin(lat1) * sin_lat_2 + cos(lat1) * cos_lat_2 * cos(lon2 - lon1)) * CONSTANTS_RADIUS_OF_EARTH;
-
-	/* 2) calculate distance rho on plane */
-	double k_bar = 0;
-	double c =  acos(sin_phi_1 * sin_lat_2 + cos_phi_1 * cos_lat_2 * cos(lon2 - lambda_0));
-
-	if (0 != c)
-		k_bar = c / sin(c);
-
-	double x2 = k_bar * (cos_lat_2 * sin(lon2 - lambda_0)); //Projection of point 2 on plane
-	double y2 = k_bar * ((cos_phi_1 * sin_lat_2 - sin_phi_1 * cos_lat_2 * cos(lon2 - lambda_0)));
-	double rho = sqrt(pow(x2, 2) + pow(y2, 2));
-
-	scale = d / rho;
+	ref->lat = lat_0 / 180.0 * M_PI;
+	ref->lon = lon_0 / 180.0 * M_PI;
 
+	ref->sin_lat = sin(ref->lat);
+	ref->cos_lat = cos(ref->lat);
 }
 
-__EXPORT void map_projection_project(double lat, double lon, float *x, float *y)
+__EXPORT void map_projection_project(struct map_projection_reference_s *ref, double lat, double lon, float *x, float *y)
 {
-	/* notation and formulas accoring to: http://mathworld.wolfram.com/AzimuthalEquidistantProjection.html */
-	double phi = lat / 180.0 * M_PI;
-	double lambda = lon / 180.0 * M_PI;
-
-	double sin_phi = sin(phi);
-	double cos_phi = cos(phi);
-
-	double k_bar = 0;
-	/* using small angle approximation (formula in comment is without aproximation) */
-	double c =  acos(sin_phi_1 * sin_phi + cos_phi_1 * cos_phi * (1 - pow((lambda - lambda_0), 2) / 2)); //double c =  acos( sin_phi_1 * sin_phi + cos_phi_1 * cos_phi * cos(lambda - lambda_0) );
+	double lat_rad = lat / 180.0 * M_PI;
+	double lon_rad = lon / 180.0 * M_PI;
 
-	if (0 != c)
-		k_bar = c / sin(c);
+	double sin_lat = sin(lat_rad);
+	double cos_lat = cos(lat_rad);
+	double cos_d_lon = cos(lon_rad - ref->lon);
 
-	/* using small angle approximation (formula in comment is without aproximation) */
-	*y = k_bar * (cos_phi * (lambda - lambda_0)) * scale;//*y = k_bar * (cos_phi * sin(lambda - lambda_0)) * scale;
-	*x = k_bar * ((cos_phi_1 * sin_phi - sin_phi_1 * cos_phi * (1 - pow((lambda - lambda_0), 2) / 2))) * scale; //	*x = k_bar * ((cos_phi_1 * sin_phi - sin_phi_1 * cos_phi * cos(lambda - lambda_0))) * scale;
+	double c = acos(ref->sin_lat * sin_lat + ref->cos_lat * cos_lat * cos_d_lon);
+	double k = (c == 0.0) ? 1.0 : (c / sin(c));
 
-//	printf("%phi_1=%.10f, lambda_0 =%.10f\n", phi_1, lambda_0);
+	*x = k * (ref->cos_lat * sin_lat - ref->sin_lat * cos_lat * cos_d_lon) * CONSTANTS_RADIUS_OF_EARTH;
+	*y = k * cos_lat * sin(lon_rad - ref->lon) * CONSTANTS_RADIUS_OF_EARTH;
 }
 
-__EXPORT void map_projection_reproject(float x, float y, double *lat, double *lon)
+__EXPORT void map_projection_reproject(struct map_projection_reference_s *ref, float x, float y, double *lat, double *lon)
 {
-	/* notation and formulas accoring to: http://mathworld.wolfram.com/AzimuthalEquidistantProjection.html */
-
-	double x_descaled = x / scale;
-	double y_descaled = y / scale;
-
-	double c = sqrt(pow(x_descaled, 2) + pow(y_descaled, 2));
+	float x_rad = x / CONSTANTS_RADIUS_OF_EARTH;
+	float y_rad = y / CONSTANTS_RADIUS_OF_EARTH;
+	double c = sqrtf(x_rad * x_rad + y_rad * y_rad);
 	double sin_c = sin(c);
 	double cos_c = cos(c);
 
-	double lat_sphere = 0;
-
-	if (c != 0)
-		lat_sphere = asin(cos_c * sin_phi_1 + (x_descaled * sin_c * cos_phi_1) / c);
-	else
-		lat_sphere = asin(cos_c * sin_phi_1);
-
-//	printf("lat_sphere = %.10f\n",lat_sphere);
-
-	double lon_sphere = 0;
-
-	if (phi_1  == M_PI / 2) {
-		//using small angle approximation (formula in comment is without aproximation)
-		lon_sphere = (lambda_0 - y_descaled / x_descaled); //lon_sphere = (lambda_0 + atan2(-y_descaled, x_descaled));
+	double lat_rad;
+	double lon_rad;
 
-	} else if (phi_1 == -M_PI / 2) {
-		//using small angle approximation (formula in comment is without aproximation)
-		lon_sphere = (lambda_0 + y_descaled / x_descaled); //lon_sphere = (lambda_0 + atan2(y_descaled, x_descaled));
+	if (c != 0.0) {
+		lat_rad = asin(cos_c * ref->sin_lat + (x_rad * sin_c * ref->cos_lat) / c);
+		lon_rad = (ref->lon + atan2(y_rad * sin_c, c * ref->cos_lat * cos_c - x_rad * ref->sin_lat * sin_c));
 
 	} else {
-
-		lon_sphere = (lambda_0 + atan2(y_descaled * sin_c , c * cos_phi_1 * cos_c - x_descaled * sin_phi_1 * sin_c));
-		//using small angle approximation
-//    	double denominator = (c * cos_phi_1 * cos_c - x_descaled * sin_phi_1 * sin_c);
-//    	if(denominator != 0)
-//    	{
-//    		lon_sphere = (lambda_0 + (y_descaled * sin_c) / denominator);
-//    	}
-//    	else
-//    	{
-//    	...
-//    	}
+		lat_rad = ref->lat;
+		lon_rad = ref->lon;
 	}
 
-//	printf("lon_sphere = %.10f\n",lon_sphere);
-
-	*lat = lat_sphere * 180.0 / M_PI;
-	*lon = lon_sphere * 180.0 / M_PI;
-
+	*lat = lat_rad * 180.0 / M_PI;
+	*lon = lon_rad * 180.0 / M_PI;
 }
 
 
@@ -207,7 +139,7 @@ __EXPORT float get_bearing_to_next_waypoint(double lat_now, double lon_now, doub
 	return theta;
 }
 
-__EXPORT void get_vector_to_next_waypoint(double lat_now, double lon_now, double lat_next, double lon_next, float* v_n, float* v_e)
+__EXPORT void get_vector_to_next_waypoint(double lat_now, double lon_now, double lat_next, double lon_next, float *v_n, float *v_e)
 {
 	double lat_now_rad = lat_now * M_DEG_TO_RAD;
 	double lon_now_rad = lon_now * M_DEG_TO_RAD;
@@ -222,7 +154,7 @@ __EXPORT void get_vector_to_next_waypoint(double lat_now, double lon_now, double
 	*v_e = CONSTANTS_RADIUS_OF_EARTH * sin(d_lon) * cos(lat_next_rad);
 }
 
-__EXPORT void get_vector_to_next_waypoint_fast(double lat_now, double lon_now, double lat_next, double lon_next, float* v_n, float* v_e)
+__EXPORT void get_vector_to_next_waypoint_fast(double lat_now, double lon_now, double lat_next, double lon_next, float *v_n, float *v_e)
 {
 	double lat_now_rad = lat_now * M_DEG_TO_RAD;
 	double lon_now_rad = lon_now * M_DEG_TO_RAD;
@@ -248,7 +180,7 @@ __EXPORT void add_vector_to_global_position(double lat_now, double lon_now, floa
 
 // Additional functions - @author Doug Weibel <douglas.weibel@colorado.edu>
 
-__EXPORT int get_distance_to_line(struct crosstrack_error_s * crosstrack_error, double lat_now, double lon_now, double lat_start, double lon_start, double lat_end, double lon_end)
+__EXPORT int get_distance_to_line(struct crosstrack_error_s *crosstrack_error, double lat_now, double lon_now, double lat_start, double lon_start, double lat_end, double lon_end)
 {
 // This function returns the distance to the nearest point on the track line.  Distance is positive if current
 // position is right of the track and negative if left of the track as seen from a point on the track line
@@ -265,7 +197,7 @@ __EXPORT int get_distance_to_line(struct crosstrack_error_s * crosstrack_error,
 	crosstrack_error->bearing = 0.0f;
 
 	// Return error if arguments are bad
-	if (lat_now == 0.0d || lon_now == 0.0d || lat_start == 0.0d || lon_start == 0.0d || lat_end == 0.0d || lon_end == 0.0d) return return_value;
+	if (lat_now == 0.0d || lon_now == 0.0d || lat_start == 0.0d || lon_start == 0.0d || lat_end == 0.0d || lon_end == 0.0d) { return return_value; }
 
 	bearing_end = get_bearing_to_next_waypoint(lat_now, lon_now, lat_end, lon_end);
 	bearing_track = get_bearing_to_next_waypoint(lat_start, lon_start, lat_end, lon_end);
@@ -296,8 +228,8 @@ __EXPORT int get_distance_to_line(struct crosstrack_error_s * crosstrack_error,
 }
 
 
-__EXPORT int get_distance_to_arc(struct crosstrack_error_s * crosstrack_error, double lat_now, double lon_now, double lat_center, double lon_center,
-		float radius, float arc_start_bearing, float arc_sweep)
+__EXPORT int get_distance_to_arc(struct crosstrack_error_s *crosstrack_error, double lat_now, double lon_now, double lat_center, double lon_center,
+				 float radius, float arc_start_bearing, float arc_sweep)
 {
 	// This function returns the distance to the nearest point on the track arc.  Distance is positive if current
 	// position is right of the arc and negative if left of the arc as seen from the closest point on the arc and
@@ -316,29 +248,29 @@ __EXPORT int get_distance_to_arc(struct crosstrack_error_s * crosstrack_error, d
 	crosstrack_error->bearing = 0.0f;
 
 	// Return error if arguments are bad
-	if (lat_now == 0.0d || lon_now == 0.0d || lat_center == 0.0d || lon_center == 0.0d || radius == 0.0d) return return_value;
+	if (lat_now == 0.0d || lon_now == 0.0d || lat_center == 0.0d || lon_center == 0.0d || radius == 0.0d) { return return_value; }
 
 
 	if (arc_sweep >= 0) {
 		bearing_sector_start = arc_start_bearing;
 		bearing_sector_end = arc_start_bearing + arc_sweep;
 
-		if (bearing_sector_end > 2.0f * M_PI_F) bearing_sector_end -= M_TWOPI_F;
+		if (bearing_sector_end > 2.0f * M_PI_F) { bearing_sector_end -= M_TWOPI_F; }
 
 	} else {
 		bearing_sector_end = arc_start_bearing;
 		bearing_sector_start = arc_start_bearing - arc_sweep;
 
-		if (bearing_sector_start < 0.0f) bearing_sector_start += M_TWOPI_F;
+		if (bearing_sector_start < 0.0f) { bearing_sector_start += M_TWOPI_F; }
 	}
 
 	in_sector = false;
 
 	// Case where sector does not span zero
-	if (bearing_sector_end >= bearing_sector_start && bearing_now >= bearing_sector_start && bearing_now <= bearing_sector_end) in_sector = true;
+	if (bearing_sector_end >= bearing_sector_start && bearing_now >= bearing_sector_start && bearing_now <= bearing_sector_end) { in_sector = true; }
 
 	// Case where sector does span zero
-	if (bearing_sector_end < bearing_sector_start && (bearing_now > bearing_sector_start || bearing_now < bearing_sector_end)) in_sector = true;
+	if (bearing_sector_end < bearing_sector_start && (bearing_now > bearing_sector_start || bearing_now < bearing_sector_end)) { in_sector = true; }
 
 	// If in the sector then calculate distance and bearing to closest point
 	if (in_sector) {
@@ -394,8 +326,8 @@ __EXPORT int get_distance_to_arc(struct crosstrack_error_s * crosstrack_error, d
 }
 
 __EXPORT float get_distance_to_point_global_wgs84(double lat_now, double lon_now, float alt_now,
-	                                          double lat_next, double lon_next, float alt_next,
-	                                          float *dist_xy, float *dist_z)
+		double lat_next, double lon_next, float alt_next,
+		float *dist_xy, float *dist_z)
 {
 	double current_x_rad = lat_next / 180.0 * M_PI;
 	double current_y_rad = lon_next / 180.0 * M_PI;
@@ -419,8 +351,8 @@ __EXPORT float get_distance_to_point_global_wgs84(double lat_now, double lon_now
 
 
 __EXPORT float mavlink_wpm_distance_to_point_local(float x_now, float y_now, float z_now,
-	                                           float x_next, float y_next, float z_next,
-	                                           float *dist_xy, float *dist_z)
+		float x_next, float y_next, float z_next,
+		float *dist_xy, float *dist_z)
 {
 	float dx = x_now - x_next;
 	float dy = y_now - y_next;
@@ -442,15 +374,19 @@ __EXPORT float _wrap_pi(float bearing)
 	int c = 0;
 	while (bearing >= M_PI_F) {
 		bearing -= M_TWOPI_F;
-		if (c++ > 3)
+
+		if (c++ > 3) {
 			return NAN;
+		}
 	}
 
 	c = 0;
 	while (bearing < -M_PI_F) {
 		bearing += M_TWOPI_F;
-		if (c++ > 3)
+
+		if (c++ > 3) {
 			return NAN;
+		}
 	}
 
 	return bearing;
@@ -466,15 +402,19 @@ __EXPORT float _wrap_2pi(float bearing)
 	int c = 0;
 	while (bearing >= M_TWOPI_F) {
 		bearing -= M_TWOPI_F;
-		if (c++ > 3)
+
+		if (c++ > 3) {
 			return NAN;
+		}
 	}
 
 	c = 0;
 	while (bearing < 0.0f) {
 		bearing += M_TWOPI_F;
-		if (c++ > 3)
+
+		if (c++ > 3) {
 			return NAN;
+		}
 	}
 
 	return bearing;
@@ -490,15 +430,19 @@ __EXPORT float _wrap_180(float bearing)
 	int c = 0;
 	while (bearing >= 180.0f) {
 		bearing -= 360.0f;
-		if (c++ > 3)
+
+		if (c++ > 3) {
 			return NAN;
+		}
 	}
 
 	c = 0;
 	while (bearing < -180.0f) {
 		bearing += 360.0f;
-		if (c++ > 3)
+
+		if (c++ > 3) {
 			return NAN;
+		}
 	}
 
 	return bearing;
@@ -514,15 +458,19 @@ __EXPORT float _wrap_360(float bearing)
 	int c = 0;
 	while (bearing >= 360.0f) {
 		bearing -= 360.0f;
-		if (c++ > 3)
+
+		if (c++ > 3) {
 			return NAN;
+		}
 	}
 
 	c = 0;
 	while (bearing < 0.0f) {
 		bearing += 360.0f;
-		if (c++ > 3)
+
+		if (c++ > 3) {
 			return NAN;
+		}
 	}
 
 	return bearing;
diff --git a/src/lib/geo/geo.h b/src/lib/geo/geo.h
index 94afb4df0..0a3f85d97 100644
--- a/src/lib/geo/geo.h
+++ b/src/lib/geo/geo.h
@@ -1,9 +1,6 @@
 /****************************************************************************
  *
- *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
- *   Author: Thomas Gubler <thomasgubler@student.ethz.ch>
- *           Julian Oes <joes@student.ethz.ch>
- *           Lorenz Meier <lm@inf.ethz.ch>
+ *   Copyright (C) 2012, 2014 PX4 Development Team. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -42,6 +39,7 @@
  * @author Thomas Gubler <thomasgubler@student.ethz.ch>
  * @author Julian Oes <joes@student.ethz.ch>
  * @author Lorenz Meier <lm@inf.ethz.ch>
+ * @author Anton Babushkin <anton.babushkin@me.com>
  * Additional functions - @author Doug Weibel <douglas.weibel@colorado.edu>
  */
 
@@ -67,6 +65,14 @@ struct crosstrack_error_s {
 	float bearing;		// Bearing in radians to closest point on line/arc
 } ;
 
+/* lat/lon are in radians */
+struct map_projection_reference_s {
+	double lat;
+	double lon;
+	double sin_lat;
+	double cos_lat;
+};
+
 /**
  * Initializes the map transformation.
  *
@@ -74,7 +80,7 @@ struct crosstrack_error_s {
  * @param lat in degrees (47.1234567°, not 471234567°)
  * @param lon in degrees (8.1234567°, not 81234567°)
  */
-__EXPORT void map_projection_init(double lat_0, double lon_0);
+__EXPORT void map_projection_init(struct map_projection_reference_s *ref, double lat_0, double lon_0);
 
 /**
  * Transforms a point in the geographic coordinate system to the local azimuthal equidistant plane
@@ -83,7 +89,7 @@ __EXPORT void map_projection_init(double lat_0, double lon_0);
  * @param lat in degrees (47.1234567°, not 471234567°)
  * @param lon in degrees (8.1234567°, not 81234567°)
  */
-__EXPORT void map_projection_project(double lat, double lon, float *x, float *y);
+__EXPORT void map_projection_project(struct map_projection_reference_s *ref, double lat, double lon, float *x, float *y);
 
 /**
  * Transforms a point in the local azimuthal equidistant plane to the geographic coordinate system
@@ -93,7 +99,7 @@ __EXPORT void map_projection_project(double lat, double lon, float *x, float *y)
  * @param lat in degrees (47.1234567°, not 471234567°)
  * @param lon in degrees (8.1234567°, not 81234567°)
  */
-__EXPORT void map_projection_reproject(float x, float y, double *lat, double *lon);
+__EXPORT void map_projection_reproject(struct map_projection_reference_s *ref, float x, float y, double *lat, double *lon);
 
 /**
  * Returns the distance to the next waypoint in meters.
@@ -115,30 +121,30 @@ __EXPORT float get_distance_to_next_waypoint(double lat_now, double lon_now, dou
  */
 __EXPORT float get_bearing_to_next_waypoint(double lat_now, double lon_now, double lat_next, double lon_next);
 
-__EXPORT void get_vector_to_next_waypoint(double lat_now, double lon_now, double lat_next, double lon_next, float* v_n, float* v_e);
+__EXPORT void get_vector_to_next_waypoint(double lat_now, double lon_now, double lat_next, double lon_next, float *v_n, float *v_e);
 
-__EXPORT void get_vector_to_next_waypoint_fast(double lat_now, double lon_now, double lat_next, double lon_next, float* v_n, float* v_e);
+__EXPORT void get_vector_to_next_waypoint_fast(double lat_now, double lon_now, double lat_next, double lon_next, float *v_n, float *v_e);
 
 __EXPORT void add_vector_to_global_position(double lat_now, double lon_now, float v_n, float v_e, double *lat_res, double *lon_res);
 
-__EXPORT int get_distance_to_line(struct crosstrack_error_s * crosstrack_error, double lat_now, double lon_now, double lat_start, double lon_start, double lat_end, double lon_end);
+__EXPORT int get_distance_to_line(struct crosstrack_error_s *crosstrack_error, double lat_now, double lon_now, double lat_start, double lon_start, double lat_end, double lon_end);
 
-__EXPORT int get_distance_to_arc(struct crosstrack_error_s * crosstrack_error, double lat_now, double lon_now, double lat_center, double lon_center,
-		float radius, float arc_start_bearing, float arc_sweep);
+__EXPORT int get_distance_to_arc(struct crosstrack_error_s *crosstrack_error, double lat_now, double lon_now, double lat_center, double lon_center,
+				 float radius, float arc_start_bearing, float arc_sweep);
 
 /*
  * Calculate distance in global frame
  */
 __EXPORT float get_distance_to_point_global_wgs84(double lat_now, double lon_now, float alt_now,
-	                                          double lat_next, double lon_next, float alt_next,
-	                                          float *dist_xy, float *dist_z);
+		double lat_next, double lon_next, float alt_next,
+		float *dist_xy, float *dist_z);
 
 /*
  * Calculate distance in local frame (NED)
  */
 __EXPORT float mavlink_wpm_distance_to_point_local(float x_now, float y_now, float z_now,
-	                                           float x_next, float y_next, float z_next,
-	                                           float *dist_xy, float *dist_z);
+		float x_next, float y_next, float z_next,
+		float *dist_xy, float *dist_z);
 
 __EXPORT float _wrap_180(float bearing);
 __EXPORT float _wrap_360(float bearing);
diff --git a/src/modules/att_pos_estimator_ekf/KalmanNav.cpp b/src/modules/att_pos_estimator_ekf/KalmanNav.cpp
deleted file mode 100644
index 668bac5d9..000000000
--- a/src/modules/att_pos_estimator_ekf/KalmanNav.cpp
+++ /dev/null
@@ -1,815 +0,0 @@
-/****************************************************************************
- *
- *   Copyright (c) 2012, 2013 PX4 Development Team. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in
- *    the documentation and/or other materials provided with the
- *    distribution.
- * 3. Neither the name PX4 nor the names of its contributors may be
- *    used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- ****************************************************************************/
-
-/**
- * @file KalmanNav.cpp
- *
- * Kalman filter navigation code
- */
-
-#include <poll.h>
-
-#include "KalmanNav.hpp"
-#include <systemlib/err.h>
-#include <geo/geo.h>
-
-// constants
-// Titterton pg. 52
-static const float omega = 7.2921150e-5f; // earth rotation rate, rad/s
-static const float R0 = 6378137.0f; // earth radius, m
-static const float g0 = 9.806f; // standard gravitational accel. m/s^2
-static const int8_t ret_ok = 0; 		// no error in function
-static const int8_t ret_error = -1; 	// error occurred
-
-KalmanNav::KalmanNav(SuperBlock *parent, const char *name) :
-	SuperBlock(parent, name),
-	// subscriptions
-	_sensors(&getSubscriptions(), ORB_ID(sensor_combined), 5), // limit to 200 Hz
-	_gps(&getSubscriptions(), ORB_ID(vehicle_gps_position), 100), // limit to 10 Hz
-	_param_update(&getSubscriptions(), ORB_ID(parameter_update), 1000), // limit to 1 Hz
-	// publications
-	_pos(&getPublications(), ORB_ID(vehicle_global_position)),
-	_localPos(&getPublications(), ORB_ID(vehicle_local_position)),
-	_att(&getPublications(), ORB_ID(vehicle_attitude)),
-	// timestamps
-	_pubTimeStamp(hrt_absolute_time()),
-	_predictTimeStamp(hrt_absolute_time()),
-	_attTimeStamp(hrt_absolute_time()),
-	_outTimeStamp(hrt_absolute_time()),
-	// frame count
-	_navFrames(0),
-	// miss counts
-	_miss(0),
-	// accelerations
-	fN(0), fE(0), fD(0),
-	// state
-	phi(0), theta(0), psi(0),
-	vN(0), vE(0), vD(0),
-	lat(0), lon(0), alt(0),
-	lat0(0), lon0(0), alt0(0),
-	// parameters for ground station
-	_vGyro(this, "V_GYRO"),
-	_vAccel(this, "V_ACCEL"),
-	_rMag(this, "R_MAG"),
-	_rGpsVel(this, "R_GPS_VEL"),
-	_rGpsPos(this, "R_GPS_POS"),
-	_rGpsAlt(this, "R_GPS_ALT"),
-	_rPressAlt(this, "R_PRESS_ALT"),
-	_rAccel(this, "R_ACCEL"),
-	_magDip(this, "ENV_MAG_DIP"),
-	_magDec(this, "ENV_MAG_DEC"),
-	_g(this, "ENV_G"),
-	_faultPos(this, "FAULT_POS"),
-	_faultAtt(this, "FAULT_ATT"),
-	_attitudeInitialized(false),
-	_positionInitialized(false),
-	_attitudeInitCounter(0)
-{
-	using namespace math;
-
-	F.zero();
-	G.zero();
-	V.zero();
-	HAtt.zero();
-	RAtt.zero();
-	HPos.zero();
-	RPos.zero();
-
-	// initial state covariance matrix
-	P0.identity();
-	P0 *= 0.01f;
-	P = P0;
-
-	// initial state
-	phi = 0.0f;
-	theta = 0.0f;
-	psi = 0.0f;
-	vN = 0.0f;
-	vE = 0.0f;
-	vD = 0.0f;
-	lat = 0.0f;
-	lon = 0.0f;
-	alt = 0.0f;
-
-	// initialize rotation quaternion with a single raw sensor measurement
-	_sensors.update();
-	q = init(
-		_sensors.accelerometer_m_s2[0],
-		_sensors.accelerometer_m_s2[1],
-		_sensors.accelerometer_m_s2[2],
-		_sensors.magnetometer_ga[0],
-		_sensors.magnetometer_ga[1],
-		_sensors.magnetometer_ga[2]);
-
-	// initialize dcm
-	C_nb = q.to_dcm();
-
-	// HPos is constant
-	HPos(0, 3) = 1.0f;
-	HPos(1, 4) = 1.0f;
-	HPos(2, 6) = 1.0e7f * M_RAD_TO_DEG_F;
-	HPos(3, 7) = 1.0e7f * M_RAD_TO_DEG_F;
-	HPos(4, 8) = 1.0f;
-	HPos(5, 8) = 1.0f;
-
-	// initialize all parameters
-	updateParams();
-}
-
-math::Quaternion KalmanNav::init(float ax, float ay, float az, float mx, float my, float mz)
-{
-    float initialRoll, initialPitch;
-    float cosRoll, sinRoll, cosPitch, sinPitch;
-    float magX, magY;
-    float initialHdg, cosHeading, sinHeading;
-
-    initialRoll = atan2(-ay, -az);
-    initialPitch = atan2(ax, -az);
-
-    cosRoll = cosf(initialRoll);
-    sinRoll = sinf(initialRoll);
-    cosPitch = cosf(initialPitch);
-    sinPitch = sinf(initialPitch);
-
-    magX = mx * cosPitch + my * sinRoll * sinPitch + mz * cosRoll * sinPitch;
-
-    magY = my * cosRoll - mz * sinRoll;
-
-    initialHdg = atan2f(-magY, magX);
-
-    cosRoll = cosf(initialRoll * 0.5f);
-    sinRoll = sinf(initialRoll * 0.5f);
-
-    cosPitch = cosf(initialPitch * 0.5f);
-    sinPitch = sinf(initialPitch * 0.5f);
-
-    cosHeading = cosf(initialHdg * 0.5f);
-    sinHeading = sinf(initialHdg * 0.5f);
-
-    float q0 = cosRoll * cosPitch * cosHeading + sinRoll * sinPitch * sinHeading;
-    float q1 = sinRoll * cosPitch * cosHeading - cosRoll * sinPitch * sinHeading;
-    float q2 = cosRoll * sinPitch * cosHeading + sinRoll * cosPitch * sinHeading;
-    float q3 = cosRoll * cosPitch * sinHeading - sinRoll * sinPitch * cosHeading;
-
-    return math::Quaternion(q0, q1, q2, q3);
-
-}
-
-void KalmanNav::update()
-{
-	using namespace math;
-
-	struct pollfd fds[1];
-	fds[0].fd = _sensors.getHandle();
-	fds[0].events = POLLIN;
-
-	// poll for new data
-	int ret = poll(fds, 1, 1000);
-
-	if (ret < 0) {
-		// XXX this is seriously bad - should be an emergency
-		return;
-
-	} else if (ret == 0) { // timeout
-		return;
-	}
-
-	// get new timestamp
-	uint64_t newTimeStamp = hrt_absolute_time();
-
-	// check updated subscriptions
-	if (_param_update.updated()) updateParams();
-
-	bool gpsUpdate = _gps.updated();
-	bool sensorsUpdate = _sensors.updated();
-
-	// get new information from subscriptions
-	// this clears update flag
-	updateSubscriptions();
-
-	// initialize attitude when sensors online
-	if (!_attitudeInitialized && sensorsUpdate) {
-		if (correctAtt() == ret_ok) _attitudeInitCounter++;
-
-		if (_attitudeInitCounter > 100) {
-			warnx("initialized EKF attitude");
-			warnx("phi: %8.4f, theta: %8.4f, psi: %8.4f",
-			       double(phi), double(theta), double(psi));
-			_attitudeInitialized = true;
-		}
-	}
-
-	// initialize position when gps received
-	if (!_positionInitialized &&
-	    _attitudeInitialized && // wait for attitude first
-	    gpsUpdate &&
-	    _gps.fix_type > 2
-	    //&& _gps.counter_pos_valid > 10
-	   ) {
-		vN = _gps.vel_n_m_s;
-		vE = _gps.vel_e_m_s;
-		vD = _gps.vel_d_m_s;
-		setLatDegE7(_gps.lat);
-		setLonDegE7(_gps.lon);
-		setAltE3(_gps.alt);
-		// set reference position for
-		// local position
-		lat0 = lat;
-		lon0 = lon;
-		alt0 = alt;
-		// XXX map_projection has internal global
-		// states that multiple things could change, 
-		// should make map_projection take reference
-		// lat/lon and not have init
-		map_projection_init(lat0, lon0);
-		_positionInitialized = true;
-		warnx("initialized EKF state with GPS");
-		warnx("vN: %8.4f, vE: %8.4f, vD: %8.4f, lat: %8.4f, lon: %8.4f, alt: %8.4f",
-		       double(vN), double(vE), double(vD),
-		       lat, lon, double(alt));
-	}
-
-	// prediction step
-	// using sensors timestamp so we can account for packet lag
-	float dt = (_sensors.timestamp - _predictTimeStamp) / 1.0e6f;
-	//printf("dt: %15.10f\n", double(dt));
-	_predictTimeStamp = _sensors.timestamp;
-
-	// don't predict if time greater than a second
-	if (dt < 1.0f) {
-		predictState(dt);
-		predictStateCovariance(dt);
-		// count fast frames
-		_navFrames += 1;
-	}
-
-	// count times 100 Hz rate isn't met
-	if (dt > 0.01f) _miss++;
-
-	// gps correction step
-	if (_positionInitialized && gpsUpdate) {
-		correctPos();
-	}
-
-	// attitude correction step
-	if (_attitudeInitialized 								// initialized
-	    && sensorsUpdate 								// new data
-	    && _sensors.timestamp - _attTimeStamp > 1e6 / 50 	// 50 Hz
-	   ) {
-		_attTimeStamp = _sensors.timestamp;
-		correctAtt();
-	}
-
-	// publication
-	if (newTimeStamp - _pubTimeStamp > 1e6 / 50) { // 50 Hz
-		_pubTimeStamp = newTimeStamp;
-
-		updatePublications();
-	}
-
-	// output
-	if (newTimeStamp - _outTimeStamp > 10e6) { // 0.1 Hz
-		_outTimeStamp = newTimeStamp;
-		//printf("nav: %4d Hz, miss #: %4d\n",
-		//       _navFrames / 10, _miss / 10);
-		_navFrames = 0;
-		_miss = 0;
-	}
-}
-
-void KalmanNav::updatePublications()
-{
-	using namespace math;
-
-	// global position publication
-	_pos.timestamp = _pubTimeStamp;
-	_pos.time_gps_usec = _gps.timestamp_position;
-	_pos.global_valid = true;
-	_pos.lat = lat * M_RAD_TO_DEG;
-	_pos.lon = lon * M_RAD_TO_DEG;
-	_pos.alt = float(alt);
-	_pos.vel_n = vN;
-	_pos.vel_e = vE;
-	_pos.vel_d = vD;
-	_pos.yaw = psi;
-
-	// local position publication
-	float x;
-	float y;
-	bool landed = alt < (alt0 + 0.1); // XXX improve?
-	map_projection_project(lat, lon, &x, &y); 
-	_localPos.timestamp = _pubTimeStamp;
-	_localPos.xy_valid = true;
-	_localPos.z_valid = true;
-	_localPos.v_xy_valid = true;
-	_localPos.v_z_valid = true;
-	_localPos.x = x;
-	_localPos.y = y;
-	_localPos.z = alt0 - alt;
-	_localPos.vx = vN;
-	_localPos.vy = vE;
-	_localPos.vz = vD;
-	_localPos.yaw = psi;
-	_localPos.xy_global = true;
-	_localPos.z_global = true;
-	_localPos.ref_timestamp = _pubTimeStamp;
-	_localPos.ref_lat = getLatDegE7();
-	_localPos.ref_lon = getLonDegE7();
-	_localPos.ref_alt = 0;
-	_localPos.landed = landed;
-
-	// attitude publication
-	_att.timestamp = _pubTimeStamp;
-	_att.roll = phi;
-	_att.pitch = theta;
-	_att.yaw = psi;
-	_att.rollspeed = _sensors.gyro_rad_s[0];
-	_att.pitchspeed = _sensors.gyro_rad_s[1];
-	_att.yawspeed = _sensors.gyro_rad_s[2];
-	// TODO, add gyro offsets to filter
-	_att.rate_offsets[0] = 0.0f;
-	_att.rate_offsets[1] = 0.0f;
-	_att.rate_offsets[2] = 0.0f;
-
-	for (int i = 0; i < 3; i++) for (int j = 0; j < 3; j++)
-			_att.R[i][j] = C_nb(i, j);
-
-	for (int i = 0; i < 4; i++) _att.q[i] = q(i);
-
-	_att.R_valid = true;
-	_att.q_valid = true;
-
-	// selectively update publications,
-	// do NOT call superblock do-all method
-	if (_positionInitialized) {
-		_pos.update();
-		_localPos.update();
-	}
-
-	if (_attitudeInitialized)
-		_att.update();
-}
-
-int KalmanNav::predictState(float dt)
-{
-	using namespace math;
-
-	// trig
-	float sinL = sinf(lat);
-	float cosL = cosf(lat);
-	float cosLSing = cosf(lat);
-
-	// prevent singularity
-	if (fabsf(cosLSing) < 0.01f) {
-		if (cosLSing > 0) cosLSing = 0.01;
-		else cosLSing = -0.01;
-	}
-
-	// attitude prediction
-	if (_attitudeInitialized) {
-		Vector<3> w(_sensors.gyro_rad_s);
-
-		// attitude
-		q = q + q.derivative(w) * dt;
-
-		// renormalize quaternion if needed
-		if (fabsf(q.length() - 1.0f) > 1e-4f) {
-			q.normalize();
-		}
-
-		// C_nb update
-		C_nb = q.to_dcm();
-
-		// euler update
-		Vector<3> euler = C_nb.to_euler();
-		phi = euler.data[0];
-		theta = euler.data[1];
-		psi = euler.data[2];
-
-		// specific acceleration in nav frame
-		Vector<3> accelB(_sensors.accelerometer_m_s2);
-		Vector<3> accelN = C_nb * accelB;
-		fN = accelN(0);
-		fE = accelN(1);
-		fD = accelN(2);
-	}
-
-	// position prediction
-	if (_positionInitialized) {
-		// neglects angular deflections in local gravity
-		// see Titerton pg. 70
-		float R = R0 + float(alt);
-		float LDot = vN / R;
-		float lDot = vE / (cosLSing * R);
-		float rotRate = 2 * omega + lDot;
-
-		// XXX position prediction using speed
-		float vNDot = fN - vE * rotRate * sinL +
-			      vD * LDot;
-		float vDDot = fD - vE * rotRate * cosL -
-			      vN * LDot + _g.get();
-		float vEDot = fE + vN * rotRate * sinL +
-			      vDDot * rotRate * cosL;
-
-		// rectangular integration
-		vN += vNDot * dt;
-		vE += vEDot * dt;
-		vD += vDDot * dt;
-		lat += double(LDot * dt);
-		lon += double(lDot * dt);
-		alt += double(-vD * dt);
-	}
-
-	return ret_ok;
-}
-
-int KalmanNav::predictStateCovariance(float dt)
-{
-	using namespace math;
-
-	// trig
-	float sinL = sinf(lat);
-	float cosL = cosf(lat);
-	float cosLSq = cosL * cosL;
-	float tanL = tanf(lat);
-
-	// prepare for matrix
-	float R = R0 + float(alt);
-	float RSq = R * R;
-
-	// F Matrix
-	// Titterton pg. 291
-
-	F(0, 1) = -(omega * sinL + vE * tanL / R);
-	F(0, 2) = vN / R;
-	F(0, 4) = 1.0f / R;
-	F(0, 6) = -omega * sinL;
-	F(0, 8) = -vE / RSq;
-
-	F(1, 0) = omega * sinL + vE * tanL / R;
-	F(1, 2) = omega * cosL + vE / R;
-	F(1, 3) = -1.0f / R;
-	F(1, 8) = vN / RSq;
-
-	F(2, 0) = -vN / R;
-	F(2, 1) = -omega * cosL - vE / R;
-	F(2, 4) = -tanL / R;
-	F(2, 6) = -omega * cosL - vE / (R * cosLSq);
-	F(2, 8) = vE * tanL / RSq;
-
-	F(3, 1) = -fD;
-	F(3, 2) = fE;
-	F(3, 3) = vD / R;
-	F(3, 4) = -2 * (omega * sinL + vE * tanL / R);
-	F(3, 5) = vN / R;
-	F(3, 6) = -vE * (2 * omega * cosL + vE / (R * cosLSq));
-	F(3, 8) = (vE * vE * tanL - vN * vD) / RSq;
-
-	F(4, 0) = fD;
-	F(4, 2) = -fN;
-	F(4, 3) = 2 * omega * sinL + vE * tanL / R;
-	F(4, 4) = (vN * tanL + vD) / R;
-	F(4, 5) = 2 * omega * cosL + vE / R;
-	F(4, 6) = 2 * omega * (vN * cosL - vD * sinL) +
-		  vN * vE / (R * cosLSq);
-	F(4, 8) = -vE * (vN * tanL + vD) / RSq;
-
-	F(5, 0) = -fE;
-	F(5, 1) = fN;
-	F(5, 3) = -2 * vN / R;
-	F(5, 4) = -2 * (omega * cosL + vE / R);
-	F(5, 6) = 2 * omega * vE * sinL;
-	F(5, 8) = (vN * vN + vE * vE) / RSq;
-
-	F(6, 3) = 1 / R;
-	F(6, 8) = -vN / RSq;
-
-	F(7, 4) = 1 / (R * cosL);
-	F(7, 6) = vE * tanL / (R * cosL);
-	F(7, 8) = -vE / (cosL * RSq);
-
-	F(8, 5) = -1;
-
-	// G Matrix
-	// Titterton pg. 291
-	G(0, 0) = -C_nb(0, 0);
-	G(0, 1) = -C_nb(0, 1);
-	G(0, 2) = -C_nb(0, 2);
-	G(1, 0) = -C_nb(1, 0);
-	G(1, 1) = -C_nb(1, 1);
-	G(1, 2) = -C_nb(1, 2);
-	G(2, 0) = -C_nb(2, 0);
-	G(2, 1) = -C_nb(2, 1);
-	G(2, 2) = -C_nb(2, 2);
-
-	G(3, 3) = C_nb(0, 0);
-	G(3, 4) = C_nb(0, 1);
-	G(3, 5) = C_nb(0, 2);
-	G(4, 3) = C_nb(1, 0);
-	G(4, 4) = C_nb(1, 1);
-	G(4, 5) = C_nb(1, 2);
-	G(5, 3) = C_nb(2, 0);
-	G(5, 4) = C_nb(2, 1);
-	G(5, 5) = C_nb(2, 2);
-
-	// continuous prediction equations
-	// for discrete time EKF
-	// http://en.wikipedia.org/wiki/Extended_Kalman_filter
-	P = P + (F * P + P * F.transposed() + G * V * G.transposed()) * dt;
-
-	return ret_ok;
-}
-
-int KalmanNav::correctAtt()
-{
-	using namespace math;
-
-	// trig
-	float cosPhi = cosf(phi);
-	float cosTheta = cosf(theta);
-	// float cosPsi = cosf(psi);
-	float sinPhi = sinf(phi);
-	float sinTheta = sinf(theta);
-	// float sinPsi = sinf(psi);
-
-	// mag predicted measurement
-	// choosing some typical magnetic field properties,
-	//  TODO dip/dec depend on lat/ lon/ time
-	//float dip = _magDip.get() / M_RAD_TO_DEG_F; // dip, inclination with level
-	float dec = _magDec.get() / M_RAD_TO_DEG_F; // declination, clockwise rotation from north
-
-	// compensate roll and pitch, but not yaw
-	// XXX take the vectors out of the C_nb matrix to avoid singularities
-	math::Matrix<3,3> C_rp;
-	C_rp.from_euler(phi, theta, 0.0f);//C_nb.transposed();
-
-	// mag measurement
-	Vector<3> magBody(_sensors.magnetometer_ga);
-
-	// transform to earth frame
-	Vector<3> magNav = C_rp * magBody;
-
-	// calculate error between estimate and measurement
-	// apply declination correction for true heading as well.
-	float yMag = -atan2f(magNav(1),magNav(0)) - psi - dec;
-	if (yMag > M_PI_F) yMag -= 2*M_PI_F;
-	if (yMag < -M_PI_F) yMag += 2*M_PI_F;
-
-	// accel measurement
-	Vector<3> zAccel(_sensors.accelerometer_m_s2);
-	float accelMag = zAccel.length();
-	zAccel.normalize();
-
-	// ignore accel correction when accel mag not close to g
-	Matrix<4,4> RAttAdjust = RAtt;
-
-	bool ignoreAccel = fabsf(accelMag - _g.get()) > 1.1f;
-
-	if (ignoreAccel) {
-		RAttAdjust(1, 1) = 1.0e10;
-		RAttAdjust(2, 2) = 1.0e10;
-		RAttAdjust(3, 3) = 1.0e10;
-
-	} else {
-		//printf("correcting attitude with accel\n");
-	}
-
-	// accel predicted measurement
-	Vector<3> zAccelHat = (C_nb.transposed() * Vector<3>(0, 0, -_g.get())).normalized();
-
-	// calculate residual
-	Vector<4> y(yMag, zAccel(0) - zAccelHat(0), zAccel(1) - zAccelHat(1), zAccel(2) - zAccelHat(2));
-
-	// HMag
-	HAtt(0, 2) = 1;
-
-	// HAccel
-	HAtt(1, 1) = cosTheta;
-	HAtt(2, 0) = -cosPhi * cosTheta;
-	HAtt(2, 1) = sinPhi * sinTheta;
-	HAtt(3, 0) = sinPhi * cosTheta;
-	HAtt(3, 1) = cosPhi * sinTheta;
-
-	// compute correction
-	// http://en.wikipedia.org/wiki/Extended_Kalman_filter
-	Matrix<4, 4> S = HAtt * P * HAtt.transposed() + RAttAdjust; // residual covariance
-	Matrix<9, 4> K = P * HAtt.transposed() * S.inversed();
-	Vector<9> xCorrect = K * y;
-
-	// check correciton is sane
-	for (size_t i = 0; i < xCorrect.get_size(); i++) {
-		float val = xCorrect(i);
-
-		if (isnan(val) || isinf(val)) {
-			// abort correction and return
-			warnx("numerical failure in att correction");
-			// reset P matrix to P0
-			P = P0;
-			return ret_error;
-		}
-	}
-
-	// correct state
-	if (!ignoreAccel) {
-		phi += xCorrect(PHI);
-		theta += xCorrect(THETA);
-	}
-
-	psi += xCorrect(PSI);
-
-	// attitude also affects nav velocities
-	if (_positionInitialized) {
-		vN += xCorrect(VN);
-		vE += xCorrect(VE);
-		vD += xCorrect(VD);
-	}
-
-	// update state covariance
-	// http://en.wikipedia.org/wiki/Extended_Kalman_filter
-	P = P - K * HAtt * P;
-
-	// fault detection
-	float beta = y * (S.inversed() * y);
-
-	if (beta > _faultAtt.get()) {
-		warnx("fault in attitude: beta = %8.4f", (double)beta);
-		warnx("y:"); y.print();
-	}
-
-	// update quaternions from euler
-	// angle correction
-	q.from_euler(phi, theta, psi);
-
-	return ret_ok;
-}
-
-int KalmanNav::correctPos()
-{
-	using namespace math;
-
-	// residual
-	Vector<6> y;
-	y(0) = _gps.vel_n_m_s - vN;
-	y(1) = _gps.vel_e_m_s - vE;
-	y(2) = double(_gps.lat) - double(lat) * 1.0e7 * M_RAD_TO_DEG;
-	y(3) = double(_gps.lon) - double(lon) * 1.0e7 * M_RAD_TO_DEG;
-	y(4) = _gps.alt / 1.0e3f - alt;
-	y(5) = _sensors.baro_alt_meter - alt;
-
-	// compute correction
-	// http://en.wikipedia.org/wiki/Extended_Kalman_filter
-	Matrix<6,6> S = HPos * P * HPos.transposed() + RPos; // residual covariance
-	Matrix<9,6> K = P * HPos.transposed() * S.inversed();
-	Vector<9> xCorrect = K * y;
-
-	// check correction is sane
-	for (size_t i = 0; i < xCorrect.get_size(); i++) {
-		float val = xCorrect(i);
-
-		if (!isfinite(val)) {
-			// abort correction and return
-			warnx("numerical failure in gps correction");
-			// fallback to GPS
-			vN = _gps.vel_n_m_s;
-			vE = _gps.vel_e_m_s;
-			vD = _gps.vel_d_m_s;
-			setLatDegE7(_gps.lat);
-			setLonDegE7(_gps.lon);
-			setAltE3(_gps.alt);
-			// reset P matrix to P0
-			P = P0;
-			return ret_error;
-		}
-	}
-
-	// correct state
-	vN += xCorrect(VN);
-	vE += xCorrect(VE);
-	vD += xCorrect(VD);
-	lat += double(xCorrect(LAT));
-	lon += double(xCorrect(LON));
-	alt += xCorrect(ALT);
-
-	// update state covariance
-	// http://en.wikipedia.org/wiki/Extended_Kalman_filter
-	P = P - K * HPos * P;
-
-	// fault detetcion
-	float beta = y * (S.inversed() * y);
-
-	static int counter = 0;
-	if (beta > _faultPos.get() && (counter % 10 == 0)) {
-		warnx("fault in gps: beta = %8.4f", (double)beta);
-		warnx("Y/N: vN: %8.4f, vE: %8.4f, lat: %8.4f, lon: %8.4f, alt: %8.4f, baro: %8.4f",
-		       double(y(0) / sqrtf(RPos(0, 0))),
-		       double(y(1) / sqrtf(RPos(1, 1))),
-		       double(y(2) / sqrtf(RPos(2, 2))),
-		       double(y(3) / sqrtf(RPos(3, 3))),
-		       double(y(4) / sqrtf(RPos(4, 4))),
-		       double(y(5) / sqrtf(RPos(5, 5))));
-	}
-	counter++;
-
-	return ret_ok;
-}
-
-void KalmanNav::updateParams()
-{
-	using namespace math;
-	using namespace control;
-	SuperBlock::updateParams();
-
-	// gyro noise
-	V(0, 0) = _vGyro.get();   // gyro x, rad/s
-	V(1, 1) = _vGyro.get();   // gyro y
-	V(2, 2) = _vGyro.get();   // gyro z
-
-	// accel noise
-	V(3, 3) = _vAccel.get();   // accel x, m/s^2
-	V(4, 4) = _vAccel.get();   // accel y
-	V(5, 5) = _vAccel.get();   // accel z
-
-	// magnetometer noise
-	float noiseMin = 1e-6f;
-	float noiseMagSq = _rMag.get() * _rMag.get();
-
-	if (noiseMagSq < noiseMin) noiseMagSq = noiseMin;
-
-	RAtt(0, 0) = noiseMagSq; // normalized direction
-
-	// accelerometer noise
-	float noiseAccelSq = _rAccel.get() * _rAccel.get();
-
-	// bound noise to prevent singularities
-	if (noiseAccelSq < noiseMin) noiseAccelSq = noiseMin;
-
-	RAtt(1, 1) = noiseAccelSq; // normalized direction
-	RAtt(2, 2) = noiseAccelSq;
-	RAtt(3, 3) = noiseAccelSq;
-
-	// gps noise
-	float R = R0 + float(alt);
-	float cosLSing = cosf(lat);
-
-	// prevent singularity
-	if (fabsf(cosLSing) < 0.01f) {
-		if (cosLSing > 0) cosLSing = 0.01;
-		else cosLSing = -0.01;
-	}
-
-	float noiseVel = _rGpsVel.get();
-	float noiseLatDegE7 = 1.0e7f * M_RAD_TO_DEG_F * _rGpsPos.get() / R;
-	float noiseLonDegE7 = noiseLatDegE7 / cosLSing;
-	float noiseGpsAlt = _rGpsAlt.get();
-	float noisePressAlt = _rPressAlt.get();
-
-	// bound noise to prevent singularities
-	if (noiseVel < noiseMin) noiseVel = noiseMin;
-
-	if (noiseLatDegE7 < noiseMin) noiseLatDegE7 = noiseMin;
-
-	if (noiseLonDegE7 < noiseMin) noiseLonDegE7 = noiseMin;
-
-	if (noiseGpsAlt < noiseMin) noiseGpsAlt = noiseMin;
-
-	if (noisePressAlt < noiseMin) noisePressAlt = noiseMin;
-
-	RPos(0, 0) = noiseVel * noiseVel; // vn
-	RPos(1, 1) = noiseVel * noiseVel; // ve
-	RPos(2, 2) = noiseLatDegE7 * noiseLatDegE7; // lat
-	RPos(3, 3) = noiseLonDegE7 * noiseLonDegE7; // lon
-	RPos(4, 4) = noiseGpsAlt * noiseGpsAlt; // h
-	RPos(5, 5) = noisePressAlt * noisePressAlt; // h
-	// XXX, note that RPos depends on lat, so updateParams should
-	// be called if lat changes significantly
-}
diff --git a/src/modules/att_pos_estimator_ekf/KalmanNav.hpp b/src/modules/att_pos_estimator_ekf/KalmanNav.hpp
deleted file mode 100644
index caf93bc78..000000000
--- a/src/modules/att_pos_estimator_ekf/KalmanNav.hpp
+++ /dev/null
@@ -1,192 +0,0 @@
-/****************************************************************************
- *
- *   Copyright (c) 2012, 2013 PX4 Development Team. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in
- *    the documentation and/or other materials provided with the
- *    distribution.
- * 3. Neither the name PX4 nor the names of its contributors may be
- *    used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- ****************************************************************************/
-
-/**
- * @file KalmanNav.hpp
- *
- * kalman filter navigation code
- */
-
-#pragma once
-
-//#define MATRIX_ASSERT
-//#define VECTOR_ASSERT
-
-#include <nuttx/config.h>
-
-#include <mathlib/mathlib.h>
-#include <controllib/blocks.hpp>
-#include <controllib/block/BlockParam.hpp>
-#include <uORB/Subscription.hpp>
-#include <uORB/Publication.hpp>
-
-#include <uORB/topics/vehicle_attitude.h>
-#include <uORB/topics/vehicle_global_position.h>
-#include <uORB/topics/vehicle_local_position.h>
-#include <uORB/topics/sensor_combined.h>
-#include <uORB/topics/vehicle_gps_position.h>
-#include <uORB/topics/parameter_update.h>
-
-#include <drivers/drv_accel.h>
-#include <drivers/drv_gyro.h>
-#include <drivers/drv_mag.h>
-
-#include <drivers/drv_hrt.h>
-#include <poll.h>
-#include <unistd.h>
-
-/**
- * Kalman filter navigation class
- * http://en.wikipedia.org/wiki/Extended_Kalman_filter
- * Discrete-time extended Kalman filter
- */
-class KalmanNav : public control::SuperBlock
-{
-public:
-	/**
-	 * Constructor
-	 */
-	KalmanNav(SuperBlock *parent, const char *name);
-
-	/**
-	 * Deconstuctor
-	 */
-
-	virtual ~KalmanNav() {};
-
-	math::Quaternion init(float ax, float ay, float az, float mx, float my, float mz);
-
-	/**
-	 * The main callback function for the class
-	 */
-	void update();
-
-
-	/**
-	 * Publication update
-	 */
-	virtual void updatePublications();
-
-	/**
-	 * State prediction
-	 * Continuous, non-linear
-	 */
-	int predictState(float dt);
-
-	/**
-	 * State covariance prediction
-	 * Continuous, linear
-	 */
-	int predictStateCovariance(float dt);
-
-	/**
-	 * Attitude correction
-	 */
-	int correctAtt();
-
-	/**
-	 * Position correction
-	 */
-	int correctPos();
-
-	/**
-	 * Overloaded update parameters
-	 */
-	virtual void updateParams();
-protected:
-	// kalman filter
-	math::Matrix<9,9> F;             /**< Jacobian(f,x), where dx/dt = f(x,u) */
-	math::Matrix<9,6> G;             /**< noise shaping matrix for gyro/accel */
-	math::Matrix<9,9> P;             /**< state covariance matrix */
-	math::Matrix<9,9> P0;            /**< initial state covariance matrix */
-	math::Matrix<6,6> V;             /**< gyro/ accel noise matrix */
-	math::Matrix<4,9> HAtt;          /**< attitude measurement matrix */
-	math::Matrix<4,4> RAtt;          /**< attitude measurement noise matrix */
-	math::Matrix<6,9> HPos;          /**< position measurement jacobian matrix */
-	math::Matrix<6,6> RPos;          /**< position measurement noise matrix */
-	// attitude
-	math::Matrix<3,3> C_nb;             /**< direction cosine matrix from body to nav frame */
-	math::Quaternion q;         /**< quaternion from body to nav frame */
-	// subscriptions
-	uORB::Subscription<sensor_combined_s> _sensors;          /**< sensors sub. */
-	uORB::Subscription<vehicle_gps_position_s> _gps;         /**< gps sub. */
-	uORB::Subscription<parameter_update_s> _param_update;    /**< parameter update sub. */
-	// publications
-	uORB::Publication<vehicle_global_position_s> _pos;       /**< position pub. */
-	uORB::Publication<vehicle_local_position_s> _localPos;   /**< local position pub. */
-	uORB::Publication<vehicle_attitude_s> _att;              /**< attitude pub. */
-	// time stamps
-	uint64_t _pubTimeStamp;     /**< output data publication time stamp */
-	uint64_t _predictTimeStamp; /**< prediction time stamp */
-	uint64_t _attTimeStamp;     /**< attitude correction time stamp */
-	uint64_t _outTimeStamp;     /**< output time stamp */
-	// frame count
-	uint16_t _navFrames;        /**< navigation frames completed in output cycle */
-	// miss counts
-	uint16_t _miss;         	/**< number of times fast prediction loop missed */
-	// accelerations
-	float fN, fE, fD;           /**< navigation frame acceleration */
-	// states
-	enum {PHI = 0, THETA, PSI, VN, VE, VD, LAT, LON, ALT};  /**< state enumeration */
-	float phi, theta, psi;                  /**< 3-2-1 euler angles */
-	float vN, vE, vD;                       /**< navigation velocity, m/s */
-	double lat, lon;                   	/**< lat, lon radians */
-	// parameters
-	float alt;                   		/**< altitude, meters */
-	double lat0, lon0;                   	/**< reference latitude and longitude */
-	float alt0;                   		/**<  refeerence altitude (ground height) */
-	control::BlockParamFloat _vGyro;      /**< gyro process noise */
-	control::BlockParamFloat _vAccel;     /**< accelerometer process noise  */
-	control::BlockParamFloat _rMag;       /**< magnetometer measurement noise  */
-	control::BlockParamFloat _rGpsVel;    /**< gps velocity measurement noise */
-	control::BlockParamFloat _rGpsPos;    /**< gps position measurement noise */
-	control::BlockParamFloat _rGpsAlt;    /**< gps altitude measurement noise */
-	control::BlockParamFloat _rPressAlt;  /**< press altitude measurement noise */
-	control::BlockParamFloat _rAccel;     /**< accelerometer measurement noise */
-	control::BlockParamFloat _magDip;     /**< magnetic inclination with level */
-	control::BlockParamFloat _magDec;     /**< magnetic declination, clockwise rotation */
-	control::BlockParamFloat _g;          /**< gravitational constant */
-	control::BlockParamFloat _faultPos;   /**< fault detection threshold for position */
-	control::BlockParamFloat _faultAtt;   /**< fault detection threshold for attitude */
-	// status
-	bool _attitudeInitialized;
-	bool _positionInitialized;
-	uint16_t _attitudeInitCounter;
-	// accessors
-	int32_t getLatDegE7() { return int32_t(lat * 1.0e7 * M_RAD_TO_DEG); }
-	void setLatDegE7(int32_t val) { lat = val / 1.0e7 / M_RAD_TO_DEG; }
-	int32_t getLonDegE7() { return int32_t(lon * 1.0e7 * M_RAD_TO_DEG); }
-	void setLonDegE7(int32_t val) { lon = val / 1.0e7 / M_RAD_TO_DEG; }
-	int32_t getAltE3() { return int32_t(alt * 1.0e3); }
-	void setAltE3(int32_t val) { alt = double(val) / 1.0e3; }
-};
diff --git a/src/modules/att_pos_estimator_ekf/kalman_main.cpp b/src/modules/att_pos_estimator_ekf/kalman_main.cpp
deleted file mode 100644
index 3d20d4d2d..000000000
--- a/src/modules/att_pos_estimator_ekf/kalman_main.cpp
+++ /dev/null
@@ -1,157 +0,0 @@
-/****************************************************************************
- *
- *   Copyright (c) 2012, 2013 PX4 Development Team. All rights reserved.
- *   Author: 	James Goppert
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in
- *    the documentation and/or other materials provided with the
- *    distribution.
- * 3. Neither the name PX4 nor the names of its contributors may be
- *    used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- ****************************************************************************/
-
-/**
- * @file kalman_main.cpp
- * Combined attitude / position estimator.
- *
- * @author James Goppert
- */
-
-#include <nuttx/config.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <systemlib/systemlib.h>
-#include <systemlib/param/param.h>
-#include <systemlib/err.h>
-#include <drivers/drv_hrt.h>
-#include <math.h>
-#include "KalmanNav.hpp"
-
-static bool thread_should_exit = false;     /**< Deamon exit flag */
-static bool thread_running = false;     /**< Deamon status flag */
-static int daemon_task;             /**< Handle of deamon task / thread */
-
-/**
- * Deamon management function.
- */
-extern "C" __EXPORT int att_pos_estimator_ekf_main(int argc, char *argv[]);
-
-/**
- * Mainloop of deamon.
- */
-int kalman_demo_thread_main(int argc, char *argv[]);
-
-/**
- * Print the correct usage.
- */
-static void usage(const char *reason);
-
-static void
-usage(const char *reason)
-{
-	if (reason)
-		fprintf(stderr, "%s\n", reason);
-
-	warnx("usage: att_pos_estimator_ekf {start|stop|status} [-p <additional params>]");
-	exit(1);
-}
-
-/**
- * The deamon app only briefly exists to start
- * the background job. The stack size assigned in the
- * Makefile does only apply to this management task.
- *
- * The actual stack size should be set in the call
- * to task_create().
- */
-int att_pos_estimator_ekf_main(int argc, char *argv[])
-{
-
-	if (argc < 1)
-		usage("missing command");
-
-	if (!strcmp(argv[1], "start")) {
-
-		if (thread_running) {
-			warnx("already running");
-			/* this is not an error */
-			exit(0);
-		}
-
-		thread_should_exit = false;
-
-		daemon_task = task_spawn_cmd("att_pos_estimator_ekf",
-					 SCHED_DEFAULT,
-					 SCHED_PRIORITY_MAX - 30,
-					 8192,
-					 kalman_demo_thread_main,
-					 (argv) ? (const char **)&argv[2] : (const char **)NULL);
-		exit(0);
-	}
-
-	if (!strcmp(argv[1], "stop")) {
-		thread_should_exit = true;
-		exit(0);
-	}
-
-	if (!strcmp(argv[1], "status")) {
-		if (thread_running) {
-			warnx("is running\n");
-			exit(0);
-
-		} else {
-			warnx("not started\n");
-			exit(1);
-		}
-
-	}
-
-	usage("unrecognized command");
-	exit(1);
-}
-
-int kalman_demo_thread_main(int argc, char *argv[])
-{
-
-	warnx("starting");
-
-	using namespace math;
-
-	thread_running = true;
-
-	KalmanNav nav(NULL, "KF");
-
-	while (!thread_should_exit) {
-		nav.update();
-	}
-
-	warnx("exiting.");
-
-	thread_running = false;
-
-	return 0;
-}
diff --git a/src/modules/att_pos_estimator_ekf/module.mk b/src/modules/att_pos_estimator_ekf/module.mk
deleted file mode 100644
index 8d4a40d95..000000000
--- a/src/modules/att_pos_estimator_ekf/module.mk
+++ /dev/null
@@ -1,42 +0,0 @@
-############################################################################
-#
-#   Copyright (c) 2012, 2013 PX4 Development Team. All rights reserved.
-#
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions
-# are met:
-#
-# 1. Redistributions of source code must retain the above copyright
-#    notice, this list of conditions and the following disclaimer.
-# 2. Redistributions in binary form must reproduce the above copyright
-#    notice, this list of conditions and the following disclaimer in
-#    the documentation and/or other materials provided with the
-#    distribution.
-# 3. Neither the name PX4 nor the names of its contributors may be
-#    used to endorse or promote products derived from this software
-#    without specific prior written permission.
-#
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
-# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
-# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
-# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
-# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
-# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
-# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
-# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-# POSSIBILITY OF SUCH DAMAGE.
-#
-############################################################################
-
-#
-# Full attitude / position Extended Kalman Filter
-#
-
-MODULE_COMMAND	= att_pos_estimator_ekf
-
-SRCS		= kalman_main.cpp \
-		  KalmanNav.cpp \
-		  params.c
diff --git a/src/modules/att_pos_estimator_ekf/params.c b/src/modules/att_pos_estimator_ekf/params.c
deleted file mode 100644
index 4af5edead..000000000
--- a/src/modules/att_pos_estimator_ekf/params.c
+++ /dev/null
@@ -1,49 +0,0 @@
-/****************************************************************************
- *
- *   Copyright (c) 2012, 2013 PX4 Development Team. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in
- *    the documentation and/or other materials provided with the
- *    distribution.
- * 3. Neither the name PX4 nor the names of its contributors may be
- *    used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- ****************************************************************************/
-
-#include <systemlib/param/param.h>
-
-/*PARAM_DEFINE_FLOAT(NAME,0.0f);*/
-PARAM_DEFINE_FLOAT(KF_V_GYRO, 0.008f);
-PARAM_DEFINE_FLOAT(KF_V_ACCEL, 1.0f);
-PARAM_DEFINE_FLOAT(KF_R_MAG, 0.8f);
-PARAM_DEFINE_FLOAT(KF_R_GPS_VEL, 0.5f);
-PARAM_DEFINE_FLOAT(KF_R_GPS_POS, 2.0f);
-PARAM_DEFINE_FLOAT(KF_R_GPS_ALT, 3.0f);
-PARAM_DEFINE_FLOAT(KF_R_PRESS_ALT, 0.1f);
-PARAM_DEFINE_FLOAT(KF_R_ACCEL, 1.0f);
-PARAM_DEFINE_FLOAT(KF_FAULT_POS, 10.0f);
-PARAM_DEFINE_FLOAT(KF_FAULT_ATT, 10.0f);
-PARAM_DEFINE_FLOAT(KF_ENV_G, 9.765f);
-PARAM_DEFINE_FLOAT(KF_ENV_MAG_DIP, 60.0f);
-PARAM_DEFINE_FLOAT(KF_ENV_MAG_DEC, 0.0f);
diff --git a/src/modules/attitude_estimator_ekf/attitude_estimator_ekf_main.cpp b/src/modules/attitude_estimator_ekf/attitude_estimator_ekf_main.cpp
index 10a6cd2c5..c61b6ff3f 100755
--- a/src/modules/attitude_estimator_ekf/attitude_estimator_ekf_main.cpp
+++ b/src/modules/attitude_estimator_ekf/attitude_estimator_ekf_main.cpp
@@ -407,7 +407,7 @@ const unsigned int loop_interval_alarm = 6500;	// loop interval in microseconds
 							vel(2) = gps.vel_d_m_s;
 						}
 
-					} else if (ekf_params.acc_comp == 2 && global_pos.global_valid && hrt_absolute_time() < global_pos.timestamp + 500000) {
+					} else if (ekf_params.acc_comp == 2 && gps.eph_m < 5.0f && global_pos.timestamp != 0 && hrt_absolute_time() < global_pos.timestamp + 20000) {
 						vel_valid = true;
 						if (global_pos_updated) {
 							vel_t = global_pos.timestamp;
diff --git a/src/modules/commander/commander.cpp b/src/modules/commander/commander.cpp
index 52e658019..6f86e0c2f 100644
--- a/src/modules/commander/commander.cpp
+++ b/src/modules/commander/commander.cpp
@@ -117,7 +117,7 @@ extern struct system_load_s system_load;
 #define STICK_ON_OFF_HYSTERESIS_TIME_MS 1000
 #define STICK_ON_OFF_COUNTER_LIMIT (STICK_ON_OFF_HYSTERESIS_TIME_MS*COMMANDER_MONITORING_LOOPSPERMSEC)
 
-#define POSITION_TIMEOUT 1000000 /**< consider the local or global position estimate invalid after 1s */
+#define POSITION_TIMEOUT 30000 /**< consider the local or global position estimate invalid after 30ms */
 #define RC_TIMEOUT 500000
 #define DIFFPRESS_TIMEOUT 2000000
 
@@ -153,6 +153,7 @@ static bool on_usb_power = false;
 
 static float takeoff_alt = 5.0f;
 static int parachute_enabled = 0;
+static float eph_epv_threshold = 5.0f;
 
 static struct vehicle_status_s status;
 static struct actuator_armed_s armed;
@@ -194,7 +195,7 @@ void usage(const char *reason);
 /**
  * React to commands that are sent e.g. from the mavlink module.
  */
-bool handle_command(struct vehicle_status_s *status, struct vehicle_command_s *cmd, struct actuator_armed_s *armed);
+bool handle_command(struct vehicle_status_s *status, const struct safety_s *safety, struct vehicle_command_s *cmd, struct actuator_armed_s *armed, struct home_position_s *home, struct vehicle_global_position_s *global_pos, orb_advert_t *home_pub);
 
 /**
  * Mainloop of commander.
@@ -378,7 +379,7 @@ transition_result_t arm_disarm(bool arm, const int mavlink_fd, const char* armed
     return arming_res;
 }
 
-bool handle_command(struct vehicle_status_s *status, const struct safety_s *safety, struct vehicle_command_s *cmd, struct actuator_armed_s *armed)
+bool handle_command(struct vehicle_status_s *status, const struct safety_s *safety, struct vehicle_command_s *cmd, struct actuator_armed_s *armed, struct home_position_s *home, struct vehicle_global_position_s *global_pos, orb_advert_t *home_pub)
 {
 	/* result of the command */
 	enum VEHICLE_CMD_RESULT result = VEHICLE_CMD_RESULT_UNSUPPORTED;
@@ -534,6 +535,51 @@ bool handle_command(struct vehicle_status_s *status, const struct safety_s *safe
 		}
 		break;
 
+	case VEHICLE_CMD_DO_SET_HOME: {
+			bool use_current = cmd->param1 > 0.5f;
+			if (use_current) {
+				/* use current position */
+				if (status->condition_global_position_valid) {
+					home->lat = global_pos->lat;
+					home->lon = global_pos->lon;
+					home->alt = global_pos->alt;
+
+					home->timestamp = hrt_absolute_time();
+
+					result = VEHICLE_CMD_RESULT_ACCEPTED;
+
+				} else {
+					result = VEHICLE_CMD_RESULT_TEMPORARILY_REJECTED;
+				}
+
+			} else {
+				/* use specified position */
+				home->lat = cmd->param5;
+				home->lon = cmd->param6;
+				home->alt = cmd->param7;
+
+				home->timestamp = hrt_absolute_time();
+
+				result = VEHICLE_CMD_RESULT_ACCEPTED;
+			}
+
+			if (result == VEHICLE_CMD_RESULT_ACCEPTED) {
+				warnx("home: lat = %.7f, lon = %.7f, alt = %.2f ", home->lat, home->lon, (double)home->alt);
+				mavlink_log_info(mavlink_fd, "[cmd] home: %.7f, %.7f, %.2f", home->lat, home->lon, (double)home->alt);
+
+				/* announce new home position */
+				if (*home_pub > 0) {
+					orb_publish(ORB_ID(home_position), *home_pub, home);
+
+				} else {
+					*home_pub = orb_advertise(ORB_ID(home_position), home);
+				}
+
+				/* mark home position as set */
+				status->condition_home_position_valid = true;
+			}
+		}
+		break;
 	case VEHICLE_CMD_PREFLIGHT_REBOOT_SHUTDOWN:
 	case VEHICLE_CMD_PREFLIGHT_CALIBRATION:
 	case VEHICLE_CMD_PREFLIGHT_SET_SENSOR_OFFSETS:
@@ -566,6 +612,7 @@ int commander_thread_main(int argc, char *argv[])
 	commander_initialized = false;
 
 	bool arm_tune_played = false;
+	bool was_armed = false;
 
 	/* set parameters */
 	param_t _param_sys_type = param_find("MAV_TYPE");
@@ -877,9 +924,6 @@ int commander_thread_main(int argc, char *argv[])
 			orb_copy(ORB_ID(vehicle_global_position), global_position_sub, &global_position);
 		}
 
-		/* update condition_global_position_valid */
-		check_valid(global_position.timestamp, POSITION_TIMEOUT, global_position.global_valid, &(status.condition_global_position_valid), &status_changed);
-
 		/* update local position estimate */
 		orb_check(local_position_sub, &updated);
 
@@ -888,8 +932,53 @@ int commander_thread_main(int argc, char *argv[])
 			orb_copy(ORB_ID(vehicle_local_position), local_position_sub, &local_position);
 		}
 
+		/* update condition_global_position_valid */
+		/* hysteresis for EPH/EPV */
+		bool eph_epv_good;
+		if (status.condition_global_position_valid) {
+			if (global_position.eph > eph_epv_threshold * 2.0f || global_position.epv > eph_epv_threshold * 2.0f) {
+				eph_epv_good = false;
+			}
+
+		} else {
+			if (global_position.eph < eph_epv_threshold && global_position.epv < eph_epv_threshold) {
+				eph_epv_good = true;
+			}
+		}
+		check_valid(global_position.timestamp, POSITION_TIMEOUT, eph_epv_good, &(status.condition_global_position_valid), &status_changed);
+
+		/* check if GPS fix is ok */
+
+		/* update home position */
+		if (!status.condition_home_position_valid && status.condition_global_position_valid && !armed.armed &&
+			(global_position.eph < eph_epv_threshold) && (global_position.epv < eph_epv_threshold)) {
+
+			home.lat = global_position.lat;
+			home.lon = global_position.lon;
+			home.alt = global_position.alt;
+
+			home.x = local_position.x;
+			home.y = local_position.y;
+			home.z = local_position.z;
+
+			warnx("home: lat = %.7f, lon = %.7f, alt = %.2f ", home.lat, home.lon, (double)home.alt);
+			mavlink_log_info(mavlink_fd, "[cmd] home: %.7f, %.7f, %.2f", home.lat, home.lon, (double)home.alt);
+
+			/* announce new home position */
+			if (home_pub > 0) {
+				orb_publish(ORB_ID(home_position), home_pub, &home);
+
+			} else {
+				home_pub = orb_advertise(ORB_ID(home_position), &home);
+			}
+
+			/* mark home position as set */
+			status.condition_home_position_valid = true;
+			tune_positive(true);
+		}
+
 		/* update condition_local_position_valid and condition_local_altitude_valid */
-		check_valid(local_position.timestamp, POSITION_TIMEOUT, local_position.xy_valid, &(status.condition_local_position_valid), &status_changed);
+		check_valid(local_position.timestamp, POSITION_TIMEOUT, local_position.xy_valid && eph_epv_good, &(status.condition_local_position_valid), &status_changed);
 		check_valid(local_position.timestamp, POSITION_TIMEOUT, local_position.z_valid, &(status.condition_local_altitude_valid), &status_changed);
 
 		static bool published_condition_landed_fw = false;
@@ -964,7 +1053,7 @@ int commander_thread_main(int argc, char *argv[])
 			status_changed = true;
 		}
 
-		/* update subsystem */
+		/* update position setpoint triplet */
 		orb_check(pos_sp_triplet_sub, &updated);
 
 		if (updated) {
@@ -1033,45 +1122,6 @@ int commander_thread_main(int argc, char *argv[])
 
 		if (updated) {
 			orb_copy(ORB_ID(vehicle_gps_position), gps_sub, &gps_position);
-			/* check if GPS fix is ok */
-			float hdop_threshold_m = 4.0f;
-			float vdop_threshold_m = 8.0f;
-
-			/*
-			 * If horizontal dilution of precision (hdop / eph)
-			 * and vertical diluation of precision (vdop / epv)
-			 * are below a certain threshold (e.g. 4 m), AND
-			 * home position is not yet set AND the last GPS
-			 * GPS measurement is not older than two seconds AND
-			 * the system is currently not armed, set home
-			 * position to the current position.
-			 */
-
-			if (!status.condition_home_position_valid && gps_position.fix_type >= 3 &&
-			    (gps_position.eph_m < hdop_threshold_m) && (gps_position.epv_m < vdop_threshold_m) &&
-			    (hrt_absolute_time() < gps_position.timestamp_position + POSITION_TIMEOUT) && !armed.armed
-			    && global_position.global_valid) {
-
-				/* copy position data to uORB home message, store it locally as well */
-				home.lat = global_position.lat;
-				home.lon = global_position.lon;
-				home.alt = global_position.alt;
-
-				warnx("home: lat = %.7f, lon = %.7f, alt = %.4f ", home.lat, home.lon, (double)home.alt);
-				mavlink_log_info(mavlink_fd, "[cmd] home: %.7f, %.7f, %.4f", home.lat, home.lon, (double)home.alt);
-
-				/* announce new home position */
-				if (home_pub > 0) {
-					orb_publish(ORB_ID(home_position), home_pub, &home);
-
-				} else {
-					home_pub = orb_advertise(ORB_ID(home_position), &home);
-				}
-
-				/* mark home position as set */
-				status.condition_home_position_valid = true;
-				tune_positive(true);
-			}
 		}
 
 		/* start RC input check */
@@ -1171,30 +1221,27 @@ int commander_thread_main(int argc, char *argv[])
 				mavlink_log_critical(mavlink_fd, "ERROR: main state transition denied");
 			}
 
-			if (sp_man.mode_switch == SWITCH_POS_ON) {
+			/* set navigation state */
+			/* RETURN switch, overrides MISSION switch */
+			if (sp_man.return_switch == SWITCH_POS_ON) {
+				/* switch to RTL if not already landed after RTL and home position set */
+				status.set_nav_state = NAVIGATION_STATE_RTL;
 
-				/* set navigation state */
-				/* RETURN switch, overrides MISSION switch */
-				if (sp_man.return_switch == SWITCH_POS_ON) {
-					/* switch to RTL if not already landed after RTL and home position set */
-					status.set_nav_state = NAVIGATION_STATE_RTL;
 
-				} else {
-					/* MISSION switch */
-					if (sp_man.mission_switch == SWITCH_POS_ON) {
-						/* stick is in LOITER position */
-						status.set_nav_state = NAVIGATION_STATE_LOITER;
-
-					} else if (sp_man.mission_switch != SWITCH_POS_NONE) {
-						/* stick is in MISSION position */
-						status.set_nav_state = NAVIGATION_STATE_MISSION;
-					}
-					/* XXX: I don't understand this */					
-					//else if ((sp_man.return_switch == SWITCH_POS_OFF || sp_man.return_switch == SWITCH_POS_MIDDLE) &&
-					// 		pos_sp_triplet.nav_state == NAVIGATION_STATE_RTL) {
-					// 	/* RETURN switch is in normal mode, no MISSION switch mapped, interrupt if in RTL state */
-					// 	status.set_nav_state = NAV_STATE_MISSION;
-					// }
+			} else {
+				/* MISSION switch */
+				if (sp_man.loiter_switch == SWITCH_POS_ON) {
+					/* stick is in LOITER position */
+					status.set_nav_state = NAVIGATION_STATE_LOITER;
+
+				} else if (sp_man.loiter_switch != SWITCH_POS_NONE) {
+					/* stick is in MISSION position */
+					status.set_nav_state = NAVIGATION_STATE_MISSION;
+
+				} else if ((sp_man.return_switch == SWITCH_POS_OFF || sp_man.return_switch == SWITCH_POS_MIDDLE) &&
+						pos_sp_triplet.nav_state == NAV_STATE_RTL) {
+					/* RETURN switch is in normal mode, no MISSION switch mapped, interrupt if in RTL state */
+					status.set_nav_state = NAVIGATION_STATE_MISSION;
 				}
 			}
 
@@ -1222,10 +1269,15 @@ int commander_thread_main(int argc, char *argv[])
 
 				} else {
 					/* failsafe for manual modes */
-					transition_result_t res = failsafe_state_transition(&status, FAILSAFE_STATE_RTL);
+					transition_result_t res = TRANSITION_DENIED;
+
+					if (!status.condition_landed) {
+						/* vehicle is not landed, try to perform RTL */
+						res = failsafe_state_transition(&status, FAILSAFE_STATE_RTL);
+					}
 
 					if (res == TRANSITION_DENIED) {
-						/* RTL not allowed (no global position estimate), try LAND */
+						/* RTL not allowed (no global position estimate) or not wanted, try LAND */
 						res = failsafe_state_transition(&status, FAILSAFE_STATE_LAND);
 
 						if (res == TRANSITION_DENIED) {
@@ -1259,7 +1311,7 @@ int commander_thread_main(int argc, char *argv[])
 			orb_copy(ORB_ID(vehicle_command), cmd_sub, &cmd);
 
 			/* handle it */
-			if (handle_command(&status, &safety, &cmd, &armed))
+			if (handle_command(&status, &safety, &cmd, &armed, &home, &global_position, &home_pub))
 				status_changed = true;
 		}
 
@@ -1274,7 +1326,36 @@ int commander_thread_main(int argc, char *argv[])
 		if (arming_state_changed) {
 			status_changed = true;
 			mavlink_log_info(mavlink_fd, "[cmd] arming state: %s", arming_states_str[status.arming_state]);
+
+			/* update home position on arming if at least 2s from commander start spent to avoid setting home on in-air restart */
+			if (armed.armed && !was_armed && hrt_absolute_time() > start_time + 2000000 && status.condition_global_position_valid &&
+				(global_position.eph < eph_epv_threshold) && (global_position.epv < eph_epv_threshold)) {
+
+				// TODO remove code duplication
+				home.lat = global_position.lat;
+				home.lon = global_position.lon;
+				home.alt = global_position.alt;
+
+				home.x = local_position.x;
+				home.y = local_position.y;
+				home.z = local_position.z;
+
+				warnx("home: lat = %.7f, lon = %.7f, alt = %.2f ", home.lat, home.lon, (double)home.alt);
+				mavlink_log_info(mavlink_fd, "[cmd] home: %.7f, %.7f, %.2f", home.lat, home.lon, (double)home.alt);
+
+				/* announce new home position */
+				if (home_pub > 0) {
+					orb_publish(ORB_ID(home_position), home_pub, &home);
+
+				} else {
+					home_pub = orb_advertise(ORB_ID(home_position), &home);
+				}
+
+				/* mark home position as set */
+				status.condition_home_position_valid = true;
+			}
 		}
+		was_armed = armed.armed;
 
 		if (main_state_changed) {
 			status_changed = true;
@@ -1620,8 +1701,11 @@ set_control_mode()
 		control_mode.flag_control_auto_enabled = true;
 		control_mode.flag_control_rates_enabled = true;
 		control_mode.flag_control_attitude_enabled = true;
-		control_mode.flag_control_position_enabled = true;
-		control_mode.flag_control_velocity_enabled = true;
+
+		/* in failsafe LAND mode position may be not available */
+		control_mode.flag_control_position_enabled = status.condition_local_position_valid;
+		control_mode.flag_control_velocity_enabled = status.condition_local_position_valid;
+
 		control_mode.flag_control_altitude_enabled = true;
 		control_mode.flag_control_climb_rate_enabled = true;
 	}
diff --git a/src/modules/ekf_att_pos_estimator/estimator.cpp b/src/modules/ekf_att_pos_estimator/estimator.cpp
new file mode 100644
index 000000000..6eceb21f8
--- /dev/null
+++ b/src/modules/ekf_att_pos_estimator/estimator.cpp
@@ -0,0 +1,2539 @@
+#include "estimator.h"
+#include <string.h>
+
+// Define EKF_DEBUG here to enable the debug print calls
+// if the macro is not set, these will be completely
+// optimized out by the compiler.
+#define EKF_DEBUG
+
+#ifdef EKF_DEBUG
+#include <stdio.h>
+
+static void
+ekf_debug_print(const char *fmt, va_list args)
+{
+    fprintf(stderr, "%s: ", "[ekf]");
+    vfprintf(stderr, fmt, args);
+
+    fprintf(stderr, "\n");
+}
+
+static void
+ekf_debug(const char *fmt, ...)
+{
+    va_list args;
+
+    va_start(args, fmt);
+    ekf_debug_print(fmt, args);
+}
+
+#else
+
+static void ekf_debug(const char *fmt, ...) { while(0){} }
+#endif
+
+float Vector3f::length(void) const
+{
+    return sqrt(x*x + y*y + z*z);
+}
+
+void Vector3f::zero(void)
+{
+    x = 0.0f;
+    y = 0.0f;
+    z = 0.0f;
+}
+
+Mat3f::Mat3f() {
+    identity();
+}
+
+void Mat3f::identity() {
+    x.x = 1.0f;
+    x.y = 0.0f;
+    x.z = 0.0f;
+
+    y.x = 0.0f;
+    y.y = 1.0f;
+    y.z = 0.0f;
+
+    z.x = 0.0f;
+    z.y = 0.0f;
+    z.z = 1.0f;
+}
+
+Mat3f Mat3f::transpose(void) const
+{
+    Mat3f ret = *this;
+    swap_var(ret.x.y, ret.y.x);
+    swap_var(ret.x.z, ret.z.x);
+    swap_var(ret.y.z, ret.z.y);
+    return ret;
+}
+
+// overload + operator to provide a vector addition
+Vector3f operator+( Vector3f vecIn1, Vector3f vecIn2)
+{
+    Vector3f vecOut;
+    vecOut.x = vecIn1.x + vecIn2.x;
+    vecOut.y = vecIn1.y + vecIn2.y;
+    vecOut.z = vecIn1.z + vecIn2.z;
+    return vecOut;
+}
+
+// overload - operator to provide a vector subtraction
+Vector3f operator-( Vector3f vecIn1, Vector3f vecIn2)
+{
+    Vector3f vecOut;
+    vecOut.x = vecIn1.x - vecIn2.x;
+    vecOut.y = vecIn1.y - vecIn2.y;
+    vecOut.z = vecIn1.z - vecIn2.z;
+    return vecOut;
+}
+
+// overload * operator to provide a matrix vector product
+Vector3f operator*( Mat3f matIn, Vector3f vecIn)
+{
+    Vector3f vecOut;
+    vecOut.x = matIn.x.x*vecIn.x + matIn.x.y*vecIn.y + matIn.x.z*vecIn.z;
+    vecOut.y = matIn.y.x*vecIn.x + matIn.y.y*vecIn.y + matIn.y.z*vecIn.z;
+    vecOut.z = matIn.x.x*vecIn.x + matIn.z.y*vecIn.y + matIn.z.z*vecIn.z;
+    return vecOut;
+}
+
+// overload % operator to provide a vector cross product
+Vector3f operator%( Vector3f vecIn1, Vector3f vecIn2)
+{
+    Vector3f vecOut;
+    vecOut.x = vecIn1.y*vecIn2.z - vecIn1.z*vecIn2.y;
+    vecOut.y = vecIn1.z*vecIn2.x - vecIn1.x*vecIn2.z;
+    vecOut.z = vecIn1.x*vecIn2.y - vecIn1.y*vecIn2.x;
+    return vecOut;
+}
+
+// overload * operator to provide a vector scaler product
+Vector3f operator*(Vector3f vecIn1, float sclIn1)
+{
+    Vector3f vecOut;
+    vecOut.x = vecIn1.x * sclIn1;
+    vecOut.y = vecIn1.y * sclIn1;
+    vecOut.z = vecIn1.z * sclIn1;
+    return vecOut;
+}
+
+// overload * operator to provide a vector scaler product
+Vector3f operator*(float sclIn1, Vector3f vecIn1)
+{
+    Vector3f vecOut;
+    vecOut.x = vecIn1.x * sclIn1;
+    vecOut.y = vecIn1.y * sclIn1;
+    vecOut.z = vecIn1.z * sclIn1;
+    return vecOut;
+}
+
+void swap_var(float &d1, float &d2)
+{
+    float tmp = d1;
+    d1 = d2;
+    d2 = tmp;
+}
+
+AttPosEKF::AttPosEKF() :
+    fusionModeGPS(0),
+    covSkipCount(0),
+    statesInitialised(false),
+    fuseVelData(false),
+    fusePosData(false),
+    fuseHgtData(false),
+    fuseMagData(false),
+    fuseVtasData(false),
+    onGround(true),
+    staticMode(true),
+    useAirspeed(true),
+    useCompass(true),
+    useRangeFinder(true),
+    numericalProtection(true),
+    refSet(false),
+    storeIndex(0),
+    gpsHgt(0.0f),
+    baroHgt(0.0f),
+    GPSstatus(0),
+    VtasMeas(0.0f)
+{
+    velNED[0] = 0.0f;
+    velNED[1] = 0.0f;
+    velNED[2] = 0.0f;
+
+    InitialiseParameters();
+    ZeroVariables();
+}
+
+AttPosEKF::~AttPosEKF()
+{
+}
+
+void AttPosEKF::UpdateStrapdownEquationsNED()
+{
+    Vector3f delVelNav;
+    float q00;
+    float q11;
+    float q22;
+    float q33;
+    float q01;
+    float q02;
+    float q03;
+    float q12;
+    float q13;
+    float q23;
+    float rotationMag;
+    float qUpdated[4];
+    float quatMag;
+    float deltaQuat[4];
+    const Vector3f gravityNED = {0.0,0.0,GRAVITY_MSS};
+
+// Remove sensor bias errors
+    correctedDelAng.x = dAngIMU.x - states[10];
+    correctedDelAng.y = dAngIMU.y - states[11];
+    correctedDelAng.z = dAngIMU.z - states[12];
+    dVelIMU.x = dVelIMU.x;
+    dVelIMU.y = dVelIMU.y;
+    dVelIMU.z = dVelIMU.z - states[13];
+
+// Save current measurements
+    Vector3f  prevDelAng = correctedDelAng;
+
+// Apply corrections for earths rotation rate and coning errors
+// * and + operators have been overloaded
+    correctedDelAng   = correctedDelAng - Tnb*earthRateNED*dtIMU + 8.333333333333333e-2f*(prevDelAng % correctedDelAng);
+
+// Convert the rotation vector to its equivalent quaternion
+    rotationMag = correctedDelAng.length();
+    if (rotationMag < 1e-12f)
+    {
+        deltaQuat[0] = 1.0;
+        deltaQuat[1] = 0.0;
+        deltaQuat[2] = 0.0;
+        deltaQuat[3] = 0.0;
+    }
+    else
+    {
+        deltaQuat[0] = cosf(0.5f*rotationMag);
+        float rotScaler = (sinf(0.5f*rotationMag))/rotationMag;
+        deltaQuat[1] = correctedDelAng.x*rotScaler;
+        deltaQuat[2] = correctedDelAng.y*rotScaler;
+        deltaQuat[3] = correctedDelAng.z*rotScaler;
+    }
+
+// Update the quaternions by rotating from the previous attitude through
+// the delta angle rotation quaternion
+    qUpdated[0] = states[0]*deltaQuat[0] - states[1]*deltaQuat[1] - states[2]*deltaQuat[2] - states[3]*deltaQuat[3];
+    qUpdated[1] = states[0]*deltaQuat[1] + states[1]*deltaQuat[0] + states[2]*deltaQuat[3] - states[3]*deltaQuat[2];
+    qUpdated[2] = states[0]*deltaQuat[2] + states[2]*deltaQuat[0] + states[3]*deltaQuat[1] - states[1]*deltaQuat[3];
+    qUpdated[3] = states[0]*deltaQuat[3] + states[3]*deltaQuat[0] + states[1]*deltaQuat[2] - states[2]*deltaQuat[1];
+
+// Normalise the quaternions and update the quaternion states
+    quatMag = sqrtf(sq(qUpdated[0]) + sq(qUpdated[1]) + sq(qUpdated[2]) + sq(qUpdated[3]));
+    if (quatMag > 1e-16f)
+    {
+        float quatMagInv = 1.0f/quatMag;
+        states[0] = quatMagInv*qUpdated[0];
+        states[1] = quatMagInv*qUpdated[1];
+        states[2] = quatMagInv*qUpdated[2];
+        states[3] = quatMagInv*qUpdated[3];
+    }
+
+// Calculate the body to nav cosine matrix
+    q00 = sq(states[0]);
+    q11 = sq(states[1]);
+    q22 = sq(states[2]);
+    q33 = sq(states[3]);
+    q01 =  states[0]*states[1];
+    q02 =  states[0]*states[2];
+    q03 =  states[0]*states[3];
+    q12 =  states[1]*states[2];
+    q13 =  states[1]*states[3];
+    q23 =  states[2]*states[3];
+
+    Tbn.x.x = q00 + q11 - q22 - q33;
+    Tbn.y.y = q00 - q11 + q22 - q33;
+    Tbn.z.z = q00 - q11 - q22 + q33;
+    Tbn.x.y = 2*(q12 - q03);
+    Tbn.x.z = 2*(q13 + q02);
+    Tbn.y.x = 2*(q12 + q03);
+    Tbn.y.z = 2*(q23 - q01);
+    Tbn.z.x = 2*(q13 - q02);
+    Tbn.z.y = 2*(q23 + q01);
+
+    Tnb = Tbn.transpose();
+
+// transform body delta velocities to delta velocities in the nav frame
+// * and + operators have been overloaded
+    //delVelNav = Tbn*dVelIMU + gravityNED*dtIMU;
+    delVelNav.x = Tbn.x.x*dVelIMU.x + Tbn.x.y*dVelIMU.y + Tbn.x.z*dVelIMU.z + gravityNED.x*dtIMU;
+    delVelNav.y = Tbn.y.x*dVelIMU.x + Tbn.y.y*dVelIMU.y + Tbn.y.z*dVelIMU.z + gravityNED.y*dtIMU;
+    delVelNav.z = Tbn.z.x*dVelIMU.x + Tbn.z.y*dVelIMU.y + Tbn.z.z*dVelIMU.z + gravityNED.z*dtIMU;
+
+// calculate the magnitude of the nav acceleration (required for GPS
+// variance estimation)
+    accNavMag = delVelNav.length()/dtIMU;
+
+// If calculating position save previous velocity
+    float lastVelocity[3];
+    lastVelocity[0] = states[4];
+    lastVelocity[1] = states[5];
+    lastVelocity[2] = states[6];
+
+// Sum delta velocities to get velocity
+    states[4] = states[4] + delVelNav.x;
+    states[5] = states[5] + delVelNav.y;
+    states[6] = states[6] + delVelNav.z;
+
+// If calculating postions, do a trapezoidal integration for position
+    states[7] = states[7] + 0.5f*(states[4] + lastVelocity[0])*dtIMU;
+    states[8] = states[8] + 0.5f*(states[5] + lastVelocity[1])*dtIMU;
+    states[9] = states[9] + 0.5f*(states[6] + lastVelocity[2])*dtIMU;
+
+    // Constrain states (to protect against filter divergence)
+    ConstrainStates();
+}
+
+void AttPosEKF::CovariancePrediction(float dt)
+{
+    // scalars
+    float daxCov;
+    float dayCov;
+    float dazCov;
+    float dvxCov;
+    float dvyCov;
+    float dvzCov;
+    float dvx;
+    float dvy;
+    float dvz;
+    float dax;
+    float day;
+    float daz;
+    float q0;
+    float q1;
+    float q2;
+    float q3;
+    float dax_b;
+    float day_b;
+    float daz_b;
+    float dvz_b;
+
+    // arrays
+    float processNoise[n_states];
+    float SF[15];
+    float SG[8];
+    float SQ[11];
+    float SPP[8] = {0};
+    float nextP[n_states][n_states];
+
+    // calculate covariance prediction process noise
+    for (uint8_t i= 0; i<=9;  i++) processNoise[i] = 1.0e-9f;
+    for (uint8_t i=10; i<=12; i++) processNoise[i] = dt * dAngBiasSigma;
+    // scale gyro bias noise when on ground to allow for faster bias estimation
+    for (uint8_t i=10; i<=12; i++) processNoise[i] = dt * dAngBiasSigma;
+    processNoise[13] = dVelBiasSigma;
+    for (uint8_t i=14; i<=15; i++) processNoise[i] = dt * windVelSigma;
+    for (uint8_t i=16; i<=18; i++) processNoise[i] = dt * magEarthSigma;
+    for (uint8_t i=19; i<=21; i++) processNoise[i] = dt * magBodySigma;
+    processNoise[22] = dt * sqrtf(sq(states[4]) + sq(states[5])) * gndHgtSigma;
+
+    // square all sigmas
+    for (unsigned i = 0; i < n_states; i++) processNoise[i] = sq(processNoise[i]);
+
+    // set variables used to calculate covariance growth
+    dvx = summedDelVel.x;
+    dvy = summedDelVel.y;
+    dvz = summedDelVel.z;
+    dax = summedDelAng.x;
+    day = summedDelAng.y;
+    daz = summedDelAng.z;
+    q0 = states[0];
+    q1 = states[1];
+    q2 = states[2];
+    q3 = states[3];
+    dax_b = states[10];
+    day_b = states[11];
+    daz_b = states[12];
+    dvz_b =  states[13];
+    gyroProcessNoise = ConstrainFloat(gyroProcessNoise, 1e-3f, 5e-2f);
+    daxCov = sq(dt*gyroProcessNoise);
+    dayCov = sq(dt*gyroProcessNoise);
+    dazCov = sq(dt*gyroProcessNoise);
+    if (onGround) dazCov = dazCov * sq(yawVarScale);
+    accelProcessNoise = ConstrainFloat(accelProcessNoise, 5e-2, 1.0f);
+    dvxCov = sq(dt*accelProcessNoise);
+    dvyCov = sq(dt*accelProcessNoise);
+    dvzCov = sq(dt*accelProcessNoise);
+
+    // Predicted covariance calculation
+    SF[0] = dvz - dvz_b;
+    SF[1] = 2*q3*SF[0] + 2*dvx*q1 + 2*dvy*q2;
+    SF[2] = 2*dvx*q3 - 2*q1*SF[0] + 2*dvy*q0;
+    SF[3] = 2*q2*SF[0] + 2*dvx*q0 - 2*dvy*q3;
+    SF[4] = day/2 - day_b/2;
+    SF[5] = daz/2 - daz_b/2;
+    SF[6] = dax/2 - dax_b/2;
+    SF[7] = dax_b/2 - dax/2;
+    SF[8] = daz_b/2 - daz/2;
+    SF[9] = day_b/2 - day/2;
+    SF[10] = 2*q0*SF[0];
+    SF[11] = q1/2;
+    SF[12] = q2/2;
+    SF[13] = q3/2;
+    SF[14] = 2*dvy*q1;
+
+    SG[0] = q0/2;
+    SG[1] = sq(q3);
+    SG[2] = sq(q2);
+    SG[3] = sq(q1);
+    SG[4] = sq(q0);
+    SG[5] = 2*q2*q3;
+    SG[6] = 2*q1*q3;
+    SG[7] = 2*q1*q2;
+
+    SQ[0] = dvzCov*(SG[5] - 2*q0*q1)*(SG[1] - SG[2] - SG[3] + SG[4]) - dvyCov*(SG[5] + 2*q0*q1)*(SG[1] - SG[2] + SG[3] - SG[4]) + dvxCov*(SG[6] - 2*q0*q2)*(SG[7] + 2*q0*q3);
+    SQ[1] = dvzCov*(SG[6] + 2*q0*q2)*(SG[1] - SG[2] - SG[3] + SG[4]) - dvxCov*(SG[6] - 2*q0*q2)*(SG[1] + SG[2] - SG[3] - SG[4]) + dvyCov*(SG[5] + 2*q0*q1)*(SG[7] - 2*q0*q3);
+    SQ[2] = dvzCov*(SG[5] - 2*q0*q1)*(SG[6] + 2*q0*q2) - dvyCov*(SG[7] - 2*q0*q3)*(SG[1] - SG[2] + SG[3] - SG[4]) - dvxCov*(SG[7] + 2*q0*q3)*(SG[1] + SG[2] - SG[3] - SG[4]);
+    SQ[3] = (dayCov*q1*SG[0])/2 - (dazCov*q1*SG[0])/2 - (daxCov*q2*q3)/4;
+    SQ[4] = (dazCov*q2*SG[0])/2 - (daxCov*q2*SG[0])/2 - (dayCov*q1*q3)/4;
+    SQ[5] = (daxCov*q3*SG[0])/2 - (dayCov*q3*SG[0])/2 - (dazCov*q1*q2)/4;
+    SQ[6] = (daxCov*q1*q2)/4 - (dazCov*q3*SG[0])/2 - (dayCov*q1*q2)/4;
+    SQ[7] = (dazCov*q1*q3)/4 - (daxCov*q1*q3)/4 - (dayCov*q2*SG[0])/2;
+    SQ[8] = (dayCov*q2*q3)/4 - (daxCov*q1*SG[0])/2 - (dazCov*q2*q3)/4;
+    SQ[9] = sq(SG[0]);
+    SQ[10] = sq(q1);
+
+    SPP[0] = SF[10] + SF[14] - 2*dvx*q2;
+    SPP[1] = 2*q2*SF[0] + 2*dvx*q0 - 2*dvy*q3;
+    SPP[2] = 2*dvx*q3 - 2*q1*SF[0] + 2*dvy*q0;
+    SPP[3] = 2*q0*q1 - 2*q2*q3;
+    SPP[4] = 2*q0*q2 + 2*q1*q3;
+    SPP[5] = sq(q0) - sq(q1) - sq(q2) + sq(q3);
+    SPP[6] = SF[13];
+    SPP[7] = SF[12];
+
+    nextP[0][0] = P[0][0] + P[1][0]*SF[7] + P[2][0]*SF[9] + P[3][0]*SF[8] + P[10][0]*SF[11] + P[11][0]*SPP[7] + P[12][0]*SPP[6] + (daxCov*SQ[10])/4 + SF[7]*(P[0][1] + P[1][1]*SF[7] + P[2][1]*SF[9] + P[3][1]*SF[8] + P[10][1]*SF[11] + P[11][1]*SPP[7] + P[12][1]*SPP[6]) + SF[9]*(P[0][2] + P[1][2]*SF[7] + P[2][2]*SF[9] + P[3][2]*SF[8] + P[10][2]*SF[11] + P[11][2]*SPP[7] + P[12][2]*SPP[6]) + SF[8]*(P[0][3] + P[1][3]*SF[7] + P[2][3]*SF[9] + P[3][3]*SF[8] + P[10][3]*SF[11] + P[11][3]*SPP[7] + P[12][3]*SPP[6]) + SF[11]*(P[0][10] + P[1][10]*SF[7] + P[2][10]*SF[9] + P[3][10]*SF[8] + P[10][10]*SF[11] + P[11][10]*SPP[7] + P[12][10]*SPP[6]) + SPP[7]*(P[0][11] + P[1][11]*SF[7] + P[2][11]*SF[9] + P[3][11]*SF[8] + P[10][11]*SF[11] + P[11][11]*SPP[7] + P[12][11]*SPP[6]) + SPP[6]*(P[0][12] + P[1][12]*SF[7] + P[2][12]*SF[9] + P[3][12]*SF[8] + P[10][12]*SF[11] + P[11][12]*SPP[7] + P[12][12]*SPP[6]) + (dayCov*sq(q2))/4 + (dazCov*sq(q3))/4;
+    nextP[0][1] = P[0][1] + SQ[8] + P[1][1]*SF[7] + P[2][1]*SF[9] + P[3][1]*SF[8] + P[10][1]*SF[11] + P[11][1]*SPP[7] + P[12][1]*SPP[6] + SF[6]*(P[0][0] + P[1][0]*SF[7] + P[2][0]*SF[9] + P[3][0]*SF[8] + P[10][0]*SF[11] + P[11][0]*SPP[7] + P[12][0]*SPP[6]) + SF[5]*(P[0][2] + P[1][2]*SF[7] + P[2][2]*SF[9] + P[3][2]*SF[8] + P[10][2]*SF[11] + P[11][2]*SPP[7] + P[12][2]*SPP[6]) + SF[9]*(P[0][3] + P[1][3]*SF[7] + P[2][3]*SF[9] + P[3][3]*SF[8] + P[10][3]*SF[11] + P[11][3]*SPP[7] + P[12][3]*SPP[6]) + SPP[6]*(P[0][11] + P[1][11]*SF[7] + P[2][11]*SF[9] + P[3][11]*SF[8] + P[10][11]*SF[11] + P[11][11]*SPP[7] + P[12][11]*SPP[6]) - SPP[7]*(P[0][12] + P[1][12]*SF[7] + P[2][12]*SF[9] + P[3][12]*SF[8] + P[10][12]*SF[11] + P[11][12]*SPP[7] + P[12][12]*SPP[6]) - (q0*(P[0][10] + P[1][10]*SF[7] + P[2][10]*SF[9] + P[3][10]*SF[8] + P[10][10]*SF[11] + P[11][10]*SPP[7] + P[12][10]*SPP[6]))/2;
+    nextP[0][2] = P[0][2] + SQ[7] + P[1][2]*SF[7] + P[2][2]*SF[9] + P[3][2]*SF[8] + P[10][2]*SF[11] + P[11][2]*SPP[7] + P[12][2]*SPP[6] + SF[4]*(P[0][0] + P[1][0]*SF[7] + P[2][0]*SF[9] + P[3][0]*SF[8] + P[10][0]*SF[11] + P[11][0]*SPP[7] + P[12][0]*SPP[6]) + SF[8]*(P[0][1] + P[1][1]*SF[7] + P[2][1]*SF[9] + P[3][1]*SF[8] + P[10][1]*SF[11] + P[11][1]*SPP[7] + P[12][1]*SPP[6]) + SF[6]*(P[0][3] + P[1][3]*SF[7] + P[2][3]*SF[9] + P[3][3]*SF[8] + P[10][3]*SF[11] + P[11][3]*SPP[7] + P[12][3]*SPP[6]) + SF[11]*(P[0][12] + P[1][12]*SF[7] + P[2][12]*SF[9] + P[3][12]*SF[8] + P[10][12]*SF[11] + P[11][12]*SPP[7] + P[12][12]*SPP[6]) - SPP[6]*(P[0][10] + P[1][10]*SF[7] + P[2][10]*SF[9] + P[3][10]*SF[8] + P[10][10]*SF[11] + P[11][10]*SPP[7] + P[12][10]*SPP[6]) - (q0*(P[0][11] + P[1][11]*SF[7] + P[2][11]*SF[9] + P[3][11]*SF[8] + P[10][11]*SF[11] + P[11][11]*SPP[7] + P[12][11]*SPP[6]))/2;
+    nextP[0][3] = P[0][3] + SQ[6] + P[1][3]*SF[7] + P[2][3]*SF[9] + P[3][3]*SF[8] + P[10][3]*SF[11] + P[11][3]*SPP[7] + P[12][3]*SPP[6] + SF[5]*(P[0][0] + P[1][0]*SF[7] + P[2][0]*SF[9] + P[3][0]*SF[8] + P[10][0]*SF[11] + P[11][0]*SPP[7] + P[12][0]*SPP[6]) + SF[4]*(P[0][1] + P[1][1]*SF[7] + P[2][1]*SF[9] + P[3][1]*SF[8] + P[10][1]*SF[11] + P[11][1]*SPP[7] + P[12][1]*SPP[6]) + SF[7]*(P[0][2] + P[1][2]*SF[7] + P[2][2]*SF[9] + P[3][2]*SF[8] + P[10][2]*SF[11] + P[11][2]*SPP[7] + P[12][2]*SPP[6]) - SF[11]*(P[0][11] + P[1][11]*SF[7] + P[2][11]*SF[9] + P[3][11]*SF[8] + P[10][11]*SF[11] + P[11][11]*SPP[7] + P[12][11]*SPP[6]) + SPP[7]*(P[0][10] + P[1][10]*SF[7] + P[2][10]*SF[9] + P[3][10]*SF[8] + P[10][10]*SF[11] + P[11][10]*SPP[7] + P[12][10]*SPP[6]) - (q0*(P[0][12] + P[1][12]*SF[7] + P[2][12]*SF[9] + P[3][12]*SF[8] + P[10][12]*SF[11] + P[11][12]*SPP[7] + P[12][12]*SPP[6]))/2;
+    nextP[0][4] = P[0][4] + P[1][4]*SF[7] + P[2][4]*SF[9] + P[3][4]*SF[8] + P[10][4]*SF[11] + P[11][4]*SPP[7] + P[12][4]*SPP[6] + SF[3]*(P[0][0] + P[1][0]*SF[7] + P[2][0]*SF[9] + P[3][0]*SF[8] + P[10][0]*SF[11] + P[11][0]*SPP[7] + P[12][0]*SPP[6]) + SF[1]*(P[0][1] + P[1][1]*SF[7] + P[2][1]*SF[9] + P[3][1]*SF[8] + P[10][1]*SF[11] + P[11][1]*SPP[7] + P[12][1]*SPP[6]) + SPP[0]*(P[0][2] + P[1][2]*SF[7] + P[2][2]*SF[9] + P[3][2]*SF[8] + P[10][2]*SF[11] + P[11][2]*SPP[7] + P[12][2]*SPP[6]) - SPP[2]*(P[0][3] + P[1][3]*SF[7] + P[2][3]*SF[9] + P[3][3]*SF[8] + P[10][3]*SF[11] + P[11][3]*SPP[7] + P[12][3]*SPP[6]) - SPP[4]*(P[0][13] + P[1][13]*SF[7] + P[2][13]*SF[9] + P[3][13]*SF[8] + P[10][13]*SF[11] + P[11][13]*SPP[7] + P[12][13]*SPP[6]);
+    nextP[0][5] = P[0][5] + P[1][5]*SF[7] + P[2][5]*SF[9] + P[3][5]*SF[8] + P[10][5]*SF[11] + P[11][5]*SPP[7] + P[12][5]*SPP[6] + SF[2]*(P[0][0] + P[1][0]*SF[7] + P[2][0]*SF[9] + P[3][0]*SF[8] + P[10][0]*SF[11] + P[11][0]*SPP[7] + P[12][0]*SPP[6]) + SF[1]*(P[0][2] + P[1][2]*SF[7] + P[2][2]*SF[9] + P[3][2]*SF[8] + P[10][2]*SF[11] + P[11][2]*SPP[7] + P[12][2]*SPP[6]) + SF[3]*(P[0][3] + P[1][3]*SF[7] + P[2][3]*SF[9] + P[3][3]*SF[8] + P[10][3]*SF[11] + P[11][3]*SPP[7] + P[12][3]*SPP[6]) - SPP[0]*(P[0][1] + P[1][1]*SF[7] + P[2][1]*SF[9] + P[3][1]*SF[8] + P[10][1]*SF[11] + P[11][1]*SPP[7] + P[12][1]*SPP[6]) + SPP[3]*(P[0][13] + P[1][13]*SF[7] + P[2][13]*SF[9] + P[3][13]*SF[8] + P[10][13]*SF[11] + P[11][13]*SPP[7] + P[12][13]*SPP[6]);
+    nextP[0][6] = P[0][6] + P[1][6]*SF[7] + P[2][6]*SF[9] + P[3][6]*SF[8] + P[10][6]*SF[11] + P[11][6]*SPP[7] + P[12][6]*SPP[6] + SF[2]*(P[0][1] + P[1][1]*SF[7] + P[2][1]*SF[9] + P[3][1]*SF[8] + P[10][1]*SF[11] + P[11][1]*SPP[7] + P[12][1]*SPP[6]) + SF[1]*(P[0][3] + P[1][3]*SF[7] + P[2][3]*SF[9] + P[3][3]*SF[8] + P[10][3]*SF[11] + P[11][3]*SPP[7] + P[12][3]*SPP[6]) + SPP[0]*(P[0][0] + P[1][0]*SF[7] + P[2][0]*SF[9] + P[3][0]*SF[8] + P[10][0]*SF[11] + P[11][0]*SPP[7] + P[12][0]*SPP[6]) - SPP[1]*(P[0][2] + P[1][2]*SF[7] + P[2][2]*SF[9] + P[3][2]*SF[8] + P[10][2]*SF[11] + P[11][2]*SPP[7] + P[12][2]*SPP[6]) - (sq(q0) - sq(q1) - sq(q2) + sq(q3))*(P[0][13] + P[1][13]*SF[7] + P[2][13]*SF[9] + P[3][13]*SF[8] + P[10][13]*SF[11] + P[11][13]*SPP[7] + P[12][13]*SPP[6]);
+    nextP[0][7] = P[0][7] + P[1][7]*SF[7] + P[2][7]*SF[9] + P[3][7]*SF[8] + P[10][7]*SF[11] + P[11][7]*SPP[7] + P[12][7]*SPP[6] + dt*(P[0][4] + P[1][4]*SF[7] + P[2][4]*SF[9] + P[3][4]*SF[8] + P[10][4]*SF[11] + P[11][4]*SPP[7] + P[12][4]*SPP[6]);
+    nextP[0][8] = P[0][8] + P[1][8]*SF[7] + P[2][8]*SF[9] + P[3][8]*SF[8] + P[10][8]*SF[11] + P[11][8]*SPP[7] + P[12][8]*SPP[6] + dt*(P[0][5] + P[1][5]*SF[7] + P[2][5]*SF[9] + P[3][5]*SF[8] + P[10][5]*SF[11] + P[11][5]*SPP[7] + P[12][5]*SPP[6]);
+    nextP[0][9] = P[0][9] + P[1][9]*SF[7] + P[2][9]*SF[9] + P[3][9]*SF[8] + P[10][9]*SF[11] + P[11][9]*SPP[7] + P[12][9]*SPP[6] + dt*(P[0][6] + P[1][6]*SF[7] + P[2][6]*SF[9] + P[3][6]*SF[8] + P[10][6]*SF[11] + P[11][6]*SPP[7] + P[12][6]*SPP[6]);
+    nextP[0][10] = P[0][10] + P[1][10]*SF[7] + P[2][10]*SF[9] + P[3][10]*SF[8] + P[10][10]*SF[11] + P[11][10]*SPP[7] + P[12][10]*SPP[6];
+    nextP[0][11] = P[0][11] + P[1][11]*SF[7] + P[2][11]*SF[9] + P[3][11]*SF[8] + P[10][11]*SF[11] + P[11][11]*SPP[7] + P[12][11]*SPP[6];
+    nextP[0][12] = P[0][12] + P[1][12]*SF[7] + P[2][12]*SF[9] + P[3][12]*SF[8] + P[10][12]*SF[11] + P[11][12]*SPP[7] + P[12][12]*SPP[6];
+    nextP[0][13] = P[0][13] + P[1][13]*SF[7] + P[2][13]*SF[9] + P[3][13]*SF[8] + P[10][13]*SF[11] + P[11][13]*SPP[7] + P[12][13]*SPP[6];
+    nextP[0][14] = P[0][14] + P[1][14]*SF[7] + P[2][14]*SF[9] + P[3][14]*SF[8] + P[10][14]*SF[11] + P[11][14]*SPP[7] + P[12][14]*SPP[6];
+    nextP[0][15] = P[0][15] + P[1][15]*SF[7] + P[2][15]*SF[9] + P[3][15]*SF[8] + P[10][15]*SF[11] + P[11][15]*SPP[7] + P[12][15]*SPP[6];
+    nextP[0][16] = P[0][16] + P[1][16]*SF[7] + P[2][16]*SF[9] + P[3][16]*SF[8] + P[10][16]*SF[11] + P[11][16]*SPP[7] + P[12][16]*SPP[6];
+    nextP[0][17] = P[0][17] + P[1][17]*SF[7] + P[2][17]*SF[9] + P[3][17]*SF[8] + P[10][17]*SF[11] + P[11][17]*SPP[7] + P[12][17]*SPP[6];
+    nextP[0][18] = P[0][18] + P[1][18]*SF[7] + P[2][18]*SF[9] + P[3][18]*SF[8] + P[10][18]*SF[11] + P[11][18]*SPP[7] + P[12][18]*SPP[6];
+    nextP[0][19] = P[0][19] + P[1][19]*SF[7] + P[2][19]*SF[9] + P[3][19]*SF[8] + P[10][19]*SF[11] + P[11][19]*SPP[7] + P[12][19]*SPP[6];
+    nextP[0][20] = P[0][20] + P[1][20]*SF[7] + P[2][20]*SF[9] + P[3][20]*SF[8] + P[10][20]*SF[11] + P[11][20]*SPP[7] + P[12][20]*SPP[6];
+    nextP[0][21] = P[0][21] + P[1][21]*SF[7] + P[2][21]*SF[9] + P[3][21]*SF[8] + P[10][21]*SF[11] + P[11][21]*SPP[7] + P[12][21]*SPP[6];
+    nextP[0][22] = P[0][22] + P[1][22]*SF[7] + P[2][22]*SF[9] + P[3][22]*SF[8] + P[10][22]*SF[11] + P[11][22]*SPP[7] + P[12][22]*SPP[6];
+    nextP[1][0] = P[1][0] + SQ[8] + P[0][0]*SF[6] + P[2][0]*SF[5] + P[3][0]*SF[9] + P[11][0]*SPP[6] - P[12][0]*SPP[7] - (P[10][0]*q0)/2 + SF[7]*(P[1][1] + P[0][1]*SF[6] + P[2][1]*SF[5] + P[3][1]*SF[9] + P[11][1]*SPP[6] - P[12][1]*SPP[7] - (P[10][1]*q0)/2) + SF[9]*(P[1][2] + P[0][2]*SF[6] + P[2][2]*SF[5] + P[3][2]*SF[9] + P[11][2]*SPP[6] - P[12][2]*SPP[7] - (P[10][2]*q0)/2) + SF[8]*(P[1][3] + P[0][3]*SF[6] + P[2][3]*SF[5] + P[3][3]*SF[9] + P[11][3]*SPP[6] - P[12][3]*SPP[7] - (P[10][3]*q0)/2) + SF[11]*(P[1][10] + P[0][10]*SF[6] + P[2][10]*SF[5] + P[3][10]*SF[9] + P[11][10]*SPP[6] - P[12][10]*SPP[7] - (P[10][10]*q0)/2) + SPP[7]*(P[1][11] + P[0][11]*SF[6] + P[2][11]*SF[5] + P[3][11]*SF[9] + P[11][11]*SPP[6] - P[12][11]*SPP[7] - (P[10][11]*q0)/2) + SPP[6]*(P[1][12] + P[0][12]*SF[6] + P[2][12]*SF[5] + P[3][12]*SF[9] + P[11][12]*SPP[6] - P[12][12]*SPP[7] - (P[10][12]*q0)/2);
+    nextP[1][1] = P[1][1] + P[0][1]*SF[6] + P[2][1]*SF[5] + P[3][1]*SF[9] + P[11][1]*SPP[6] - P[12][1]*SPP[7] + daxCov*SQ[9] - (P[10][1]*q0)/2 + SF[6]*(P[1][0] + P[0][0]*SF[6] + P[2][0]*SF[5] + P[3][0]*SF[9] + P[11][0]*SPP[6] - P[12][0]*SPP[7] - (P[10][0]*q0)/2) + SF[5]*(P[1][2] + P[0][2]*SF[6] + P[2][2]*SF[5] + P[3][2]*SF[9] + P[11][2]*SPP[6] - P[12][2]*SPP[7] - (P[10][2]*q0)/2) + SF[9]*(P[1][3] + P[0][3]*SF[6] + P[2][3]*SF[5] + P[3][3]*SF[9] + P[11][3]*SPP[6] - P[12][3]*SPP[7] - (P[10][3]*q0)/2) + SPP[6]*(P[1][11] + P[0][11]*SF[6] + P[2][11]*SF[5] + P[3][11]*SF[9] + P[11][11]*SPP[6] - P[12][11]*SPP[7] - (P[10][11]*q0)/2) - SPP[7]*(P[1][12] + P[0][12]*SF[6] + P[2][12]*SF[5] + P[3][12]*SF[9] + P[11][12]*SPP[6] - P[12][12]*SPP[7] - (P[10][12]*q0)/2) + (dayCov*sq(q3))/4 + (dazCov*sq(q2))/4 - (q0*(P[1][10] + P[0][10]*SF[6] + P[2][10]*SF[5] + P[3][10]*SF[9] + P[11][10]*SPP[6] - P[12][10]*SPP[7] - (P[10][10]*q0)/2))/2;
+    nextP[1][2] = P[1][2] + SQ[5] + P[0][2]*SF[6] + P[2][2]*SF[5] + P[3][2]*SF[9] + P[11][2]*SPP[6] - P[12][2]*SPP[7] - (P[10][2]*q0)/2 + SF[4]*(P[1][0] + P[0][0]*SF[6] + P[2][0]*SF[5] + P[3][0]*SF[9] + P[11][0]*SPP[6] - P[12][0]*SPP[7] - (P[10][0]*q0)/2) + SF[8]*(P[1][1] + P[0][1]*SF[6] + P[2][1]*SF[5] + P[3][1]*SF[9] + P[11][1]*SPP[6] - P[12][1]*SPP[7] - (P[10][1]*q0)/2) + SF[6]*(P[1][3] + P[0][3]*SF[6] + P[2][3]*SF[5] + P[3][3]*SF[9] + P[11][3]*SPP[6] - P[12][3]*SPP[7] - (P[10][3]*q0)/2) + SF[11]*(P[1][12] + P[0][12]*SF[6] + P[2][12]*SF[5] + P[3][12]*SF[9] + P[11][12]*SPP[6] - P[12][12]*SPP[7] - (P[10][12]*q0)/2) - SPP[6]*(P[1][10] + P[0][10]*SF[6] + P[2][10]*SF[5] + P[3][10]*SF[9] + P[11][10]*SPP[6] - P[12][10]*SPP[7] - (P[10][10]*q0)/2) - (q0*(P[1][11] + P[0][11]*SF[6] + P[2][11]*SF[5] + P[3][11]*SF[9] + P[11][11]*SPP[6] - P[12][11]*SPP[7] - (P[10][11]*q0)/2))/2;
+    nextP[1][3] = P[1][3] + SQ[4] + P[0][3]*SF[6] + P[2][3]*SF[5] + P[3][3]*SF[9] + P[11][3]*SPP[6] - P[12][3]*SPP[7] - (P[10][3]*q0)/2 + SF[5]*(P[1][0] + P[0][0]*SF[6] + P[2][0]*SF[5] + P[3][0]*SF[9] + P[11][0]*SPP[6] - P[12][0]*SPP[7] - (P[10][0]*q0)/2) + SF[4]*(P[1][1] + P[0][1]*SF[6] + P[2][1]*SF[5] + P[3][1]*SF[9] + P[11][1]*SPP[6] - P[12][1]*SPP[7] - (P[10][1]*q0)/2) + SF[7]*(P[1][2] + P[0][2]*SF[6] + P[2][2]*SF[5] + P[3][2]*SF[9] + P[11][2]*SPP[6] - P[12][2]*SPP[7] - (P[10][2]*q0)/2) - SF[11]*(P[1][11] + P[0][11]*SF[6] + P[2][11]*SF[5] + P[3][11]*SF[9] + P[11][11]*SPP[6] - P[12][11]*SPP[7] - (P[10][11]*q0)/2) + SPP[7]*(P[1][10] + P[0][10]*SF[6] + P[2][10]*SF[5] + P[3][10]*SF[9] + P[11][10]*SPP[6] - P[12][10]*SPP[7] - (P[10][10]*q0)/2) - (q0*(P[1][12] + P[0][12]*SF[6] + P[2][12]*SF[5] + P[3][12]*SF[9] + P[11][12]*SPP[6] - P[12][12]*SPP[7] - (P[10][12]*q0)/2))/2;
+    nextP[1][4] = P[1][4] + P[0][4]*SF[6] + P[2][4]*SF[5] + P[3][4]*SF[9] + P[11][4]*SPP[6] - P[12][4]*SPP[7] - (P[10][4]*q0)/2 + SF[3]*(P[1][0] + P[0][0]*SF[6] + P[2][0]*SF[5] + P[3][0]*SF[9] + P[11][0]*SPP[6] - P[12][0]*SPP[7] - (P[10][0]*q0)/2) + SF[1]*(P[1][1] + P[0][1]*SF[6] + P[2][1]*SF[5] + P[3][1]*SF[9] + P[11][1]*SPP[6] - P[12][1]*SPP[7] - (P[10][1]*q0)/2) + SPP[0]*(P[1][2] + P[0][2]*SF[6] + P[2][2]*SF[5] + P[3][2]*SF[9] + P[11][2]*SPP[6] - P[12][2]*SPP[7] - (P[10][2]*q0)/2) - SPP[2]*(P[1][3] + P[0][3]*SF[6] + P[2][3]*SF[5] + P[3][3]*SF[9] + P[11][3]*SPP[6] - P[12][3]*SPP[7] - (P[10][3]*q0)/2) - SPP[4]*(P[1][13] + P[0][13]*SF[6] + P[2][13]*SF[5] + P[3][13]*SF[9] + P[11][13]*SPP[6] - P[12][13]*SPP[7] - (P[10][13]*q0)/2);
+    nextP[1][5] = P[1][5] + P[0][5]*SF[6] + P[2][5]*SF[5] + P[3][5]*SF[9] + P[11][5]*SPP[6] - P[12][5]*SPP[7] - (P[10][5]*q0)/2 + SF[2]*(P[1][0] + P[0][0]*SF[6] + P[2][0]*SF[5] + P[3][0]*SF[9] + P[11][0]*SPP[6] - P[12][0]*SPP[7] - (P[10][0]*q0)/2) + SF[1]*(P[1][2] + P[0][2]*SF[6] + P[2][2]*SF[5] + P[3][2]*SF[9] + P[11][2]*SPP[6] - P[12][2]*SPP[7] - (P[10][2]*q0)/2) + SF[3]*(P[1][3] + P[0][3]*SF[6] + P[2][3]*SF[5] + P[3][3]*SF[9] + P[11][3]*SPP[6] - P[12][3]*SPP[7] - (P[10][3]*q0)/2) - SPP[0]*(P[1][1] + P[0][1]*SF[6] + P[2][1]*SF[5] + P[3][1]*SF[9] + P[11][1]*SPP[6] - P[12][1]*SPP[7] - (P[10][1]*q0)/2) + SPP[3]*(P[1][13] + P[0][13]*SF[6] + P[2][13]*SF[5] + P[3][13]*SF[9] + P[11][13]*SPP[6] - P[12][13]*SPP[7] - (P[10][13]*q0)/2);
+    nextP[1][6] = P[1][6] + P[0][6]*SF[6] + P[2][6]*SF[5] + P[3][6]*SF[9] + P[11][6]*SPP[6] - P[12][6]*SPP[7] - (P[10][6]*q0)/2 + SF[2]*(P[1][1] + P[0][1]*SF[6] + P[2][1]*SF[5] + P[3][1]*SF[9] + P[11][1]*SPP[6] - P[12][1]*SPP[7] - (P[10][1]*q0)/2) + SF[1]*(P[1][3] + P[0][3]*SF[6] + P[2][3]*SF[5] + P[3][3]*SF[9] + P[11][3]*SPP[6] - P[12][3]*SPP[7] - (P[10][3]*q0)/2) + SPP[0]*(P[1][0] + P[0][0]*SF[6] + P[2][0]*SF[5] + P[3][0]*SF[9] + P[11][0]*SPP[6] - P[12][0]*SPP[7] - (P[10][0]*q0)/2) - SPP[1]*(P[1][2] + P[0][2]*SF[6] + P[2][2]*SF[5] + P[3][2]*SF[9] + P[11][2]*SPP[6] - P[12][2]*SPP[7] - (P[10][2]*q0)/2) - (sq(q0) - sq(q1) - sq(q2) + sq(q3))*(P[1][13] + P[0][13]*SF[6] + P[2][13]*SF[5] + P[3][13]*SF[9] + P[11][13]*SPP[6] - P[12][13]*SPP[7] - (P[10][13]*q0)/2);
+    nextP[1][7] = P[1][7] + P[0][7]*SF[6] + P[2][7]*SF[5] + P[3][7]*SF[9] + P[11][7]*SPP[6] - P[12][7]*SPP[7] - (P[10][7]*q0)/2 + dt*(P[1][4] + P[0][4]*SF[6] + P[2][4]*SF[5] + P[3][4]*SF[9] + P[11][4]*SPP[6] - P[12][4]*SPP[7] - (P[10][4]*q0)/2);
+    nextP[1][8] = P[1][8] + P[0][8]*SF[6] + P[2][8]*SF[5] + P[3][8]*SF[9] + P[11][8]*SPP[6] - P[12][8]*SPP[7] - (P[10][8]*q0)/2 + dt*(P[1][5] + P[0][5]*SF[6] + P[2][5]*SF[5] + P[3][5]*SF[9] + P[11][5]*SPP[6] - P[12][5]*SPP[7] - (P[10][5]*q0)/2);
+    nextP[1][9] = P[1][9] + P[0][9]*SF[6] + P[2][9]*SF[5] + P[3][9]*SF[9] + P[11][9]*SPP[6] - P[12][9]*SPP[7] - (P[10][9]*q0)/2 + dt*(P[1][6] + P[0][6]*SF[6] + P[2][6]*SF[5] + P[3][6]*SF[9] + P[11][6]*SPP[6] - P[12][6]*SPP[7] - (P[10][6]*q0)/2);
+    nextP[1][10] = P[1][10] + P[0][10]*SF[6] + P[2][10]*SF[5] + P[3][10]*SF[9] + P[11][10]*SPP[6] - P[12][10]*SPP[7] - (P[10][10]*q0)/2;
+    nextP[1][11] = P[1][11] + P[0][11]*SF[6] + P[2][11]*SF[5] + P[3][11]*SF[9] + P[11][11]*SPP[6] - P[12][11]*SPP[7] - (P[10][11]*q0)/2;
+    nextP[1][12] = P[1][12] + P[0][12]*SF[6] + P[2][12]*SF[5] + P[3][12]*SF[9] + P[11][12]*SPP[6] - P[12][12]*SPP[7] - (P[10][12]*q0)/2;
+    nextP[1][13] = P[1][13] + P[0][13]*SF[6] + P[2][13]*SF[5] + P[3][13]*SF[9] + P[11][13]*SPP[6] - P[12][13]*SPP[7] - (P[10][13]*q0)/2;
+    nextP[1][14] = P[1][14] + P[0][14]*SF[6] + P[2][14]*SF[5] + P[3][14]*SF[9] + P[11][14]*SPP[6] - P[12][14]*SPP[7] - (P[10][14]*q0)/2;
+    nextP[1][15] = P[1][15] + P[0][15]*SF[6] + P[2][15]*SF[5] + P[3][15]*SF[9] + P[11][15]*SPP[6] - P[12][15]*SPP[7] - (P[10][15]*q0)/2;
+    nextP[1][16] = P[1][16] + P[0][16]*SF[6] + P[2][16]*SF[5] + P[3][16]*SF[9] + P[11][16]*SPP[6] - P[12][16]*SPP[7] - (P[10][16]*q0)/2;
+    nextP[1][17] = P[1][17] + P[0][17]*SF[6] + P[2][17]*SF[5] + P[3][17]*SF[9] + P[11][17]*SPP[6] - P[12][17]*SPP[7] - (P[10][17]*q0)/2;
+    nextP[1][18] = P[1][18] + P[0][18]*SF[6] + P[2][18]*SF[5] + P[3][18]*SF[9] + P[11][18]*SPP[6] - P[12][18]*SPP[7] - (P[10][18]*q0)/2;
+    nextP[1][19] = P[1][19] + P[0][19]*SF[6] + P[2][19]*SF[5] + P[3][19]*SF[9] + P[11][19]*SPP[6] - P[12][19]*SPP[7] - (P[10][19]*q0)/2;
+    nextP[1][20] = P[1][20] + P[0][20]*SF[6] + P[2][20]*SF[5] + P[3][20]*SF[9] + P[11][20]*SPP[6] - P[12][20]*SPP[7] - (P[10][20]*q0)/2;
+    nextP[1][21] = P[1][21] + P[0][21]*SF[6] + P[2][21]*SF[5] + P[3][21]*SF[9] + P[11][21]*SPP[6] - P[12][21]*SPP[7] - (P[10][21]*q0)/2;
+    nextP[1][22] = P[1][22] + P[0][22]*SF[6] + P[2][22]*SF[5] + P[3][22]*SF[9] + P[11][22]*SPP[6] - P[12][22]*SPP[7] - (P[10][22]*q0)/2;
+    nextP[2][0] = P[2][0] + SQ[7] + P[0][0]*SF[4] + P[1][0]*SF[8] + P[3][0]*SF[6] + P[12][0]*SF[11] - P[10][0]*SPP[6] - (P[11][0]*q0)/2 + SF[7]*(P[2][1] + P[0][1]*SF[4] + P[1][1]*SF[8] + P[3][1]*SF[6] + P[12][1]*SF[11] - P[10][1]*SPP[6] - (P[11][1]*q0)/2) + SF[9]*(P[2][2] + P[0][2]*SF[4] + P[1][2]*SF[8] + P[3][2]*SF[6] + P[12][2]*SF[11] - P[10][2]*SPP[6] - (P[11][2]*q0)/2) + SF[8]*(P[2][3] + P[0][3]*SF[4] + P[1][3]*SF[8] + P[3][3]*SF[6] + P[12][3]*SF[11] - P[10][3]*SPP[6] - (P[11][3]*q0)/2) + SF[11]*(P[2][10] + P[0][10]*SF[4] + P[1][10]*SF[8] + P[3][10]*SF[6] + P[12][10]*SF[11] - P[10][10]*SPP[6] - (P[11][10]*q0)/2) + SPP[7]*(P[2][11] + P[0][11]*SF[4] + P[1][11]*SF[8] + P[3][11]*SF[6] + P[12][11]*SF[11] - P[10][11]*SPP[6] - (P[11][11]*q0)/2) + SPP[6]*(P[2][12] + P[0][12]*SF[4] + P[1][12]*SF[8] + P[3][12]*SF[6] + P[12][12]*SF[11] - P[10][12]*SPP[6] - (P[11][12]*q0)/2);
+    nextP[2][1] = P[2][1] + SQ[5] + P[0][1]*SF[4] + P[1][1]*SF[8] + P[3][1]*SF[6] + P[12][1]*SF[11] - P[10][1]*SPP[6] - (P[11][1]*q0)/2 + SF[6]*(P[2][0] + P[0][0]*SF[4] + P[1][0]*SF[8] + P[3][0]*SF[6] + P[12][0]*SF[11] - P[10][0]*SPP[6] - (P[11][0]*q0)/2) + SF[5]*(P[2][2] + P[0][2]*SF[4] + P[1][2]*SF[8] + P[3][2]*SF[6] + P[12][2]*SF[11] - P[10][2]*SPP[6] - (P[11][2]*q0)/2) + SF[9]*(P[2][3] + P[0][3]*SF[4] + P[1][3]*SF[8] + P[3][3]*SF[6] + P[12][3]*SF[11] - P[10][3]*SPP[6] - (P[11][3]*q0)/2) + SPP[6]*(P[2][11] + P[0][11]*SF[4] + P[1][11]*SF[8] + P[3][11]*SF[6] + P[12][11]*SF[11] - P[10][11]*SPP[6] - (P[11][11]*q0)/2) - SPP[7]*(P[2][12] + P[0][12]*SF[4] + P[1][12]*SF[8] + P[3][12]*SF[6] + P[12][12]*SF[11] - P[10][12]*SPP[6] - (P[11][12]*q0)/2) - (q0*(P[2][10] + P[0][10]*SF[4] + P[1][10]*SF[8] + P[3][10]*SF[6] + P[12][10]*SF[11] - P[10][10]*SPP[6] - (P[11][10]*q0)/2))/2;
+    nextP[2][2] = P[2][2] + P[0][2]*SF[4] + P[1][2]*SF[8] + P[3][2]*SF[6] + P[12][2]*SF[11] - P[10][2]*SPP[6] + dayCov*SQ[9] + (dazCov*SQ[10])/4 - (P[11][2]*q0)/2 + SF[4]*(P[2][0] + P[0][0]*SF[4] + P[1][0]*SF[8] + P[3][0]*SF[6] + P[12][0]*SF[11] - P[10][0]*SPP[6] - (P[11][0]*q0)/2) + SF[8]*(P[2][1] + P[0][1]*SF[4] + P[1][1]*SF[8] + P[3][1]*SF[6] + P[12][1]*SF[11] - P[10][1]*SPP[6] - (P[11][1]*q0)/2) + SF[6]*(P[2][3] + P[0][3]*SF[4] + P[1][3]*SF[8] + P[3][3]*SF[6] + P[12][3]*SF[11] - P[10][3]*SPP[6] - (P[11][3]*q0)/2) + SF[11]*(P[2][12] + P[0][12]*SF[4] + P[1][12]*SF[8] + P[3][12]*SF[6] + P[12][12]*SF[11] - P[10][12]*SPP[6] - (P[11][12]*q0)/2) - SPP[6]*(P[2][10] + P[0][10]*SF[4] + P[1][10]*SF[8] + P[3][10]*SF[6] + P[12][10]*SF[11] - P[10][10]*SPP[6] - (P[11][10]*q0)/2) + (daxCov*sq(q3))/4 - (q0*(P[2][11] + P[0][11]*SF[4] + P[1][11]*SF[8] + P[3][11]*SF[6] + P[12][11]*SF[11] - P[10][11]*SPP[6] - (P[11][11]*q0)/2))/2;
+    nextP[2][3] = P[2][3] + SQ[3] + P[0][3]*SF[4] + P[1][3]*SF[8] + P[3][3]*SF[6] + P[12][3]*SF[11] - P[10][3]*SPP[6] - (P[11][3]*q0)/2 + SF[5]*(P[2][0] + P[0][0]*SF[4] + P[1][0]*SF[8] + P[3][0]*SF[6] + P[12][0]*SF[11] - P[10][0]*SPP[6] - (P[11][0]*q0)/2) + SF[4]*(P[2][1] + P[0][1]*SF[4] + P[1][1]*SF[8] + P[3][1]*SF[6] + P[12][1]*SF[11] - P[10][1]*SPP[6] - (P[11][1]*q0)/2) + SF[7]*(P[2][2] + P[0][2]*SF[4] + P[1][2]*SF[8] + P[3][2]*SF[6] + P[12][2]*SF[11] - P[10][2]*SPP[6] - (P[11][2]*q0)/2) - SF[11]*(P[2][11] + P[0][11]*SF[4] + P[1][11]*SF[8] + P[3][11]*SF[6] + P[12][11]*SF[11] - P[10][11]*SPP[6] - (P[11][11]*q0)/2) + SPP[7]*(P[2][10] + P[0][10]*SF[4] + P[1][10]*SF[8] + P[3][10]*SF[6] + P[12][10]*SF[11] - P[10][10]*SPP[6] - (P[11][10]*q0)/2) - (q0*(P[2][12] + P[0][12]*SF[4] + P[1][12]*SF[8] + P[3][12]*SF[6] + P[12][12]*SF[11] - P[10][12]*SPP[6] - (P[11][12]*q0)/2))/2;
+    nextP[2][4] = P[2][4] + P[0][4]*SF[4] + P[1][4]*SF[8] + P[3][4]*SF[6] + P[12][4]*SF[11] - P[10][4]*SPP[6] - (P[11][4]*q0)/2 + SF[3]*(P[2][0] + P[0][0]*SF[4] + P[1][0]*SF[8] + P[3][0]*SF[6] + P[12][0]*SF[11] - P[10][0]*SPP[6] - (P[11][0]*q0)/2) + SF[1]*(P[2][1] + P[0][1]*SF[4] + P[1][1]*SF[8] + P[3][1]*SF[6] + P[12][1]*SF[11] - P[10][1]*SPP[6] - (P[11][1]*q0)/2) + SPP[0]*(P[2][2] + P[0][2]*SF[4] + P[1][2]*SF[8] + P[3][2]*SF[6] + P[12][2]*SF[11] - P[10][2]*SPP[6] - (P[11][2]*q0)/2) - SPP[2]*(P[2][3] + P[0][3]*SF[4] + P[1][3]*SF[8] + P[3][3]*SF[6] + P[12][3]*SF[11] - P[10][3]*SPP[6] - (P[11][3]*q0)/2) - SPP[4]*(P[2][13] + P[0][13]*SF[4] + P[1][13]*SF[8] + P[3][13]*SF[6] + P[12][13]*SF[11] - P[10][13]*SPP[6] - (P[11][13]*q0)/2);
+    nextP[2][5] = P[2][5] + P[0][5]*SF[4] + P[1][5]*SF[8] + P[3][5]*SF[6] + P[12][5]*SF[11] - P[10][5]*SPP[6] - (P[11][5]*q0)/2 + SF[2]*(P[2][0] + P[0][0]*SF[4] + P[1][0]*SF[8] + P[3][0]*SF[6] + P[12][0]*SF[11] - P[10][0]*SPP[6] - (P[11][0]*q0)/2) + SF[1]*(P[2][2] + P[0][2]*SF[4] + P[1][2]*SF[8] + P[3][2]*SF[6] + P[12][2]*SF[11] - P[10][2]*SPP[6] - (P[11][2]*q0)/2) + SF[3]*(P[2][3] + P[0][3]*SF[4] + P[1][3]*SF[8] + P[3][3]*SF[6] + P[12][3]*SF[11] - P[10][3]*SPP[6] - (P[11][3]*q0)/2) - SPP[0]*(P[2][1] + P[0][1]*SF[4] + P[1][1]*SF[8] + P[3][1]*SF[6] + P[12][1]*SF[11] - P[10][1]*SPP[6] - (P[11][1]*q0)/2) + SPP[3]*(P[2][13] + P[0][13]*SF[4] + P[1][13]*SF[8] + P[3][13]*SF[6] + P[12][13]*SF[11] - P[10][13]*SPP[6] - (P[11][13]*q0)/2);
+    nextP[2][6] = P[2][6] + P[0][6]*SF[4] + P[1][6]*SF[8] + P[3][6]*SF[6] + P[12][6]*SF[11] - P[10][6]*SPP[6] - (P[11][6]*q0)/2 + SF[2]*(P[2][1] + P[0][1]*SF[4] + P[1][1]*SF[8] + P[3][1]*SF[6] + P[12][1]*SF[11] - P[10][1]*SPP[6] - (P[11][1]*q0)/2) + SF[1]*(P[2][3] + P[0][3]*SF[4] + P[1][3]*SF[8] + P[3][3]*SF[6] + P[12][3]*SF[11] - P[10][3]*SPP[6] - (P[11][3]*q0)/2) + SPP[0]*(P[2][0] + P[0][0]*SF[4] + P[1][0]*SF[8] + P[3][0]*SF[6] + P[12][0]*SF[11] - P[10][0]*SPP[6] - (P[11][0]*q0)/2) - SPP[1]*(P[2][2] + P[0][2]*SF[4] + P[1][2]*SF[8] + P[3][2]*SF[6] + P[12][2]*SF[11] - P[10][2]*SPP[6] - (P[11][2]*q0)/2) - (sq(q0) - sq(q1) - sq(q2) + sq(q3))*(P[2][13] + P[0][13]*SF[4] + P[1][13]*SF[8] + P[3][13]*SF[6] + P[12][13]*SF[11] - P[10][13]*SPP[6] - (P[11][13]*q0)/2);
+    nextP[2][7] = P[2][7] + P[0][7]*SF[4] + P[1][7]*SF[8] + P[3][7]*SF[6] + P[12][7]*SF[11] - P[10][7]*SPP[6] - (P[11][7]*q0)/2 + dt*(P[2][4] + P[0][4]*SF[4] + P[1][4]*SF[8] + P[3][4]*SF[6] + P[12][4]*SF[11] - P[10][4]*SPP[6] - (P[11][4]*q0)/2);
+    nextP[2][8] = P[2][8] + P[0][8]*SF[4] + P[1][8]*SF[8] + P[3][8]*SF[6] + P[12][8]*SF[11] - P[10][8]*SPP[6] - (P[11][8]*q0)/2 + dt*(P[2][5] + P[0][5]*SF[4] + P[1][5]*SF[8] + P[3][5]*SF[6] + P[12][5]*SF[11] - P[10][5]*SPP[6] - (P[11][5]*q0)/2);
+    nextP[2][9] = P[2][9] + P[0][9]*SF[4] + P[1][9]*SF[8] + P[3][9]*SF[6] + P[12][9]*SF[11] - P[10][9]*SPP[6] - (P[11][9]*q0)/2 + dt*(P[2][6] + P[0][6]*SF[4] + P[1][6]*SF[8] + P[3][6]*SF[6] + P[12][6]*SF[11] - P[10][6]*SPP[6] - (P[11][6]*q0)/2);
+    nextP[2][10] = P[2][10] + P[0][10]*SF[4] + P[1][10]*SF[8] + P[3][10]*SF[6] + P[12][10]*SF[11] - P[10][10]*SPP[6] - (P[11][10]*q0)/2;
+    nextP[2][11] = P[2][11] + P[0][11]*SF[4] + P[1][11]*SF[8] + P[3][11]*SF[6] + P[12][11]*SF[11] - P[10][11]*SPP[6] - (P[11][11]*q0)/2;
+    nextP[2][12] = P[2][12] + P[0][12]*SF[4] + P[1][12]*SF[8] + P[3][12]*SF[6] + P[12][12]*SF[11] - P[10][12]*SPP[6] - (P[11][12]*q0)/2;
+    nextP[2][13] = P[2][13] + P[0][13]*SF[4] + P[1][13]*SF[8] + P[3][13]*SF[6] + P[12][13]*SF[11] - P[10][13]*SPP[6] - (P[11][13]*q0)/2;
+    nextP[2][14] = P[2][14] + P[0][14]*SF[4] + P[1][14]*SF[8] + P[3][14]*SF[6] + P[12][14]*SF[11] - P[10][14]*SPP[6] - (P[11][14]*q0)/2;
+    nextP[2][15] = P[2][15] + P[0][15]*SF[4] + P[1][15]*SF[8] + P[3][15]*SF[6] + P[12][15]*SF[11] - P[10][15]*SPP[6] - (P[11][15]*q0)/2;
+    nextP[2][16] = P[2][16] + P[0][16]*SF[4] + P[1][16]*SF[8] + P[3][16]*SF[6] + P[12][16]*SF[11] - P[10][16]*SPP[6] - (P[11][16]*q0)/2;
+    nextP[2][17] = P[2][17] + P[0][17]*SF[4] + P[1][17]*SF[8] + P[3][17]*SF[6] + P[12][17]*SF[11] - P[10][17]*SPP[6] - (P[11][17]*q0)/2;
+    nextP[2][18] = P[2][18] + P[0][18]*SF[4] + P[1][18]*SF[8] + P[3][18]*SF[6] + P[12][18]*SF[11] - P[10][18]*SPP[6] - (P[11][18]*q0)/2;
+    nextP[2][19] = P[2][19] + P[0][19]*SF[4] + P[1][19]*SF[8] + P[3][19]*SF[6] + P[12][19]*SF[11] - P[10][19]*SPP[6] - (P[11][19]*q0)/2;
+    nextP[2][20] = P[2][20] + P[0][20]*SF[4] + P[1][20]*SF[8] + P[3][20]*SF[6] + P[12][20]*SF[11] - P[10][20]*SPP[6] - (P[11][20]*q0)/2;
+    nextP[2][21] = P[2][21] + P[0][21]*SF[4] + P[1][21]*SF[8] + P[3][21]*SF[6] + P[12][21]*SF[11] - P[10][21]*SPP[6] - (P[11][21]*q0)/2;
+    nextP[2][22] = P[2][22] + P[0][22]*SF[4] + P[1][22]*SF[8] + P[3][22]*SF[6] + P[12][22]*SF[11] - P[10][22]*SPP[6] - (P[11][22]*q0)/2;
+    nextP[3][0] = P[3][0] + SQ[6] + P[0][0]*SF[5] + P[1][0]*SF[4] + P[2][0]*SF[7] - P[11][0]*SF[11] + P[10][0]*SPP[7] - (P[12][0]*q0)/2 + SF[7]*(P[3][1] + P[0][1]*SF[5] + P[1][1]*SF[4] + P[2][1]*SF[7] - P[11][1]*SF[11] + P[10][1]*SPP[7] - (P[12][1]*q0)/2) + SF[9]*(P[3][2] + P[0][2]*SF[5] + P[1][2]*SF[4] + P[2][2]*SF[7] - P[11][2]*SF[11] + P[10][2]*SPP[7] - (P[12][2]*q0)/2) + SF[8]*(P[3][3] + P[0][3]*SF[5] + P[1][3]*SF[4] + P[2][3]*SF[7] - P[11][3]*SF[11] + P[10][3]*SPP[7] - (P[12][3]*q0)/2) + SF[11]*(P[3][10] + P[0][10]*SF[5] + P[1][10]*SF[4] + P[2][10]*SF[7] - P[11][10]*SF[11] + P[10][10]*SPP[7] - (P[12][10]*q0)/2) + SPP[7]*(P[3][11] + P[0][11]*SF[5] + P[1][11]*SF[4] + P[2][11]*SF[7] - P[11][11]*SF[11] + P[10][11]*SPP[7] - (P[12][11]*q0)/2) + SPP[6]*(P[3][12] + P[0][12]*SF[5] + P[1][12]*SF[4] + P[2][12]*SF[7] - P[11][12]*SF[11] + P[10][12]*SPP[7] - (P[12][12]*q0)/2);
+    nextP[3][1] = P[3][1] + SQ[4] + P[0][1]*SF[5] + P[1][1]*SF[4] + P[2][1]*SF[7] - P[11][1]*SF[11] + P[10][1]*SPP[7] - (P[12][1]*q0)/2 + SF[6]*(P[3][0] + P[0][0]*SF[5] + P[1][0]*SF[4] + P[2][0]*SF[7] - P[11][0]*SF[11] + P[10][0]*SPP[7] - (P[12][0]*q0)/2) + SF[5]*(P[3][2] + P[0][2]*SF[5] + P[1][2]*SF[4] + P[2][2]*SF[7] - P[11][2]*SF[11] + P[10][2]*SPP[7] - (P[12][2]*q0)/2) + SF[9]*(P[3][3] + P[0][3]*SF[5] + P[1][3]*SF[4] + P[2][3]*SF[7] - P[11][3]*SF[11] + P[10][3]*SPP[7] - (P[12][3]*q0)/2) + SPP[6]*(P[3][11] + P[0][11]*SF[5] + P[1][11]*SF[4] + P[2][11]*SF[7] - P[11][11]*SF[11] + P[10][11]*SPP[7] - (P[12][11]*q0)/2) - SPP[7]*(P[3][12] + P[0][12]*SF[5] + P[1][12]*SF[4] + P[2][12]*SF[7] - P[11][12]*SF[11] + P[10][12]*SPP[7] - (P[12][12]*q0)/2) - (q0*(P[3][10] + P[0][10]*SF[5] + P[1][10]*SF[4] + P[2][10]*SF[7] - P[11][10]*SF[11] + P[10][10]*SPP[7] - (P[12][10]*q0)/2))/2;
+    nextP[3][2] = P[3][2] + SQ[3] + P[0][2]*SF[5] + P[1][2]*SF[4] + P[2][2]*SF[7] - P[11][2]*SF[11] + P[10][2]*SPP[7] - (P[12][2]*q0)/2 + SF[4]*(P[3][0] + P[0][0]*SF[5] + P[1][0]*SF[4] + P[2][0]*SF[7] - P[11][0]*SF[11] + P[10][0]*SPP[7] - (P[12][0]*q0)/2) + SF[8]*(P[3][1] + P[0][1]*SF[5] + P[1][1]*SF[4] + P[2][1]*SF[7] - P[11][1]*SF[11] + P[10][1]*SPP[7] - (P[12][1]*q0)/2) + SF[6]*(P[3][3] + P[0][3]*SF[5] + P[1][3]*SF[4] + P[2][3]*SF[7] - P[11][3]*SF[11] + P[10][3]*SPP[7] - (P[12][3]*q0)/2) + SF[11]*(P[3][12] + P[0][12]*SF[5] + P[1][12]*SF[4] + P[2][12]*SF[7] - P[11][12]*SF[11] + P[10][12]*SPP[7] - (P[12][12]*q0)/2) - SPP[6]*(P[3][10] + P[0][10]*SF[5] + P[1][10]*SF[4] + P[2][10]*SF[7] - P[11][10]*SF[11] + P[10][10]*SPP[7] - (P[12][10]*q0)/2) - (q0*(P[3][11] + P[0][11]*SF[5] + P[1][11]*SF[4] + P[2][11]*SF[7] - P[11][11]*SF[11] + P[10][11]*SPP[7] - (P[12][11]*q0)/2))/2;
+    nextP[3][3] = P[3][3] + P[0][3]*SF[5] + P[1][3]*SF[4] + P[2][3]*SF[7] - P[11][3]*SF[11] + P[10][3]*SPP[7] + (dayCov*SQ[10])/4 + dazCov*SQ[9] - (P[12][3]*q0)/2 + SF[5]*(P[3][0] + P[0][0]*SF[5] + P[1][0]*SF[4] + P[2][0]*SF[7] - P[11][0]*SF[11] + P[10][0]*SPP[7] - (P[12][0]*q0)/2) + SF[4]*(P[3][1] + P[0][1]*SF[5] + P[1][1]*SF[4] + P[2][1]*SF[7] - P[11][1]*SF[11] + P[10][1]*SPP[7] - (P[12][1]*q0)/2) + SF[7]*(P[3][2] + P[0][2]*SF[5] + P[1][2]*SF[4] + P[2][2]*SF[7] - P[11][2]*SF[11] + P[10][2]*SPP[7] - (P[12][2]*q0)/2) - SF[11]*(P[3][11] + P[0][11]*SF[5] + P[1][11]*SF[4] + P[2][11]*SF[7] - P[11][11]*SF[11] + P[10][11]*SPP[7] - (P[12][11]*q0)/2) + SPP[7]*(P[3][10] + P[0][10]*SF[5] + P[1][10]*SF[4] + P[2][10]*SF[7] - P[11][10]*SF[11] + P[10][10]*SPP[7] - (P[12][10]*q0)/2) + (daxCov*sq(q2))/4 - (q0*(P[3][12] + P[0][12]*SF[5] + P[1][12]*SF[4] + P[2][12]*SF[7] - P[11][12]*SF[11] + P[10][12]*SPP[7] - (P[12][12]*q0)/2))/2;
+    nextP[3][4] = P[3][4] + P[0][4]*SF[5] + P[1][4]*SF[4] + P[2][4]*SF[7] - P[11][4]*SF[11] + P[10][4]*SPP[7] - (P[12][4]*q0)/2 + SF[3]*(P[3][0] + P[0][0]*SF[5] + P[1][0]*SF[4] + P[2][0]*SF[7] - P[11][0]*SF[11] + P[10][0]*SPP[7] - (P[12][0]*q0)/2) + SF[1]*(P[3][1] + P[0][1]*SF[5] + P[1][1]*SF[4] + P[2][1]*SF[7] - P[11][1]*SF[11] + P[10][1]*SPP[7] - (P[12][1]*q0)/2) + SPP[0]*(P[3][2] + P[0][2]*SF[5] + P[1][2]*SF[4] + P[2][2]*SF[7] - P[11][2]*SF[11] + P[10][2]*SPP[7] - (P[12][2]*q0)/2) - SPP[2]*(P[3][3] + P[0][3]*SF[5] + P[1][3]*SF[4] + P[2][3]*SF[7] - P[11][3]*SF[11] + P[10][3]*SPP[7] - (P[12][3]*q0)/2) - SPP[4]*(P[3][13] + P[0][13]*SF[5] + P[1][13]*SF[4] + P[2][13]*SF[7] - P[11][13]*SF[11] + P[10][13]*SPP[7] - (P[12][13]*q0)/2);
+    nextP[3][5] = P[3][5] + P[0][5]*SF[5] + P[1][5]*SF[4] + P[2][5]*SF[7] - P[11][5]*SF[11] + P[10][5]*SPP[7] - (P[12][5]*q0)/2 + SF[2]*(P[3][0] + P[0][0]*SF[5] + P[1][0]*SF[4] + P[2][0]*SF[7] - P[11][0]*SF[11] + P[10][0]*SPP[7] - (P[12][0]*q0)/2) + SF[1]*(P[3][2] + P[0][2]*SF[5] + P[1][2]*SF[4] + P[2][2]*SF[7] - P[11][2]*SF[11] + P[10][2]*SPP[7] - (P[12][2]*q0)/2) + SF[3]*(P[3][3] + P[0][3]*SF[5] + P[1][3]*SF[4] + P[2][3]*SF[7] - P[11][3]*SF[11] + P[10][3]*SPP[7] - (P[12][3]*q0)/2) - SPP[0]*(P[3][1] + P[0][1]*SF[5] + P[1][1]*SF[4] + P[2][1]*SF[7] - P[11][1]*SF[11] + P[10][1]*SPP[7] - (P[12][1]*q0)/2) + SPP[3]*(P[3][13] + P[0][13]*SF[5] + P[1][13]*SF[4] + P[2][13]*SF[7] - P[11][13]*SF[11] + P[10][13]*SPP[7] - (P[12][13]*q0)/2);
+    nextP[3][6] = P[3][6] + P[0][6]*SF[5] + P[1][6]*SF[4] + P[2][6]*SF[7] - P[11][6]*SF[11] + P[10][6]*SPP[7] - (P[12][6]*q0)/2 + SF[2]*(P[3][1] + P[0][1]*SF[5] + P[1][1]*SF[4] + P[2][1]*SF[7] - P[11][1]*SF[11] + P[10][1]*SPP[7] - (P[12][1]*q0)/2) + SF[1]*(P[3][3] + P[0][3]*SF[5] + P[1][3]*SF[4] + P[2][3]*SF[7] - P[11][3]*SF[11] + P[10][3]*SPP[7] - (P[12][3]*q0)/2) + SPP[0]*(P[3][0] + P[0][0]*SF[5] + P[1][0]*SF[4] + P[2][0]*SF[7] - P[11][0]*SF[11] + P[10][0]*SPP[7] - (P[12][0]*q0)/2) - SPP[1]*(P[3][2] + P[0][2]*SF[5] + P[1][2]*SF[4] + P[2][2]*SF[7] - P[11][2]*SF[11] + P[10][2]*SPP[7] - (P[12][2]*q0)/2) - (sq(q0) - sq(q1) - sq(q2) + sq(q3))*(P[3][13] + P[0][13]*SF[5] + P[1][13]*SF[4] + P[2][13]*SF[7] - P[11][13]*SF[11] + P[10][13]*SPP[7] - (P[12][13]*q0)/2);
+    nextP[3][7] = P[3][7] + P[0][7]*SF[5] + P[1][7]*SF[4] + P[2][7]*SF[7] - P[11][7]*SF[11] + P[10][7]*SPP[7] - (P[12][7]*q0)/2 + dt*(P[3][4] + P[0][4]*SF[5] + P[1][4]*SF[4] + P[2][4]*SF[7] - P[11][4]*SF[11] + P[10][4]*SPP[7] - (P[12][4]*q0)/2);
+    nextP[3][8] = P[3][8] + P[0][8]*SF[5] + P[1][8]*SF[4] + P[2][8]*SF[7] - P[11][8]*SF[11] + P[10][8]*SPP[7] - (P[12][8]*q0)/2 + dt*(P[3][5] + P[0][5]*SF[5] + P[1][5]*SF[4] + P[2][5]*SF[7] - P[11][5]*SF[11] + P[10][5]*SPP[7] - (P[12][5]*q0)/2);
+    nextP[3][9] = P[3][9] + P[0][9]*SF[5] + P[1][9]*SF[4] + P[2][9]*SF[7] - P[11][9]*SF[11] + P[10][9]*SPP[7] - (P[12][9]*q0)/2 + dt*(P[3][6] + P[0][6]*SF[5] + P[1][6]*SF[4] + P[2][6]*SF[7] - P[11][6]*SF[11] + P[10][6]*SPP[7] - (P[12][6]*q0)/2);
+    nextP[3][10] = P[3][10] + P[0][10]*SF[5] + P[1][10]*SF[4] + P[2][10]*SF[7] - P[11][10]*SF[11] + P[10][10]*SPP[7] - (P[12][10]*q0)/2;
+    nextP[3][11] = P[3][11] + P[0][11]*SF[5] + P[1][11]*SF[4] + P[2][11]*SF[7] - P[11][11]*SF[11] + P[10][11]*SPP[7] - (P[12][11]*q0)/2;
+    nextP[3][12] = P[3][12] + P[0][12]*SF[5] + P[1][12]*SF[4] + P[2][12]*SF[7] - P[11][12]*SF[11] + P[10][12]*SPP[7] - (P[12][12]*q0)/2;
+    nextP[3][13] = P[3][13] + P[0][13]*SF[5] + P[1][13]*SF[4] + P[2][13]*SF[7] - P[11][13]*SF[11] + P[10][13]*SPP[7] - (P[12][13]*q0)/2;
+    nextP[3][14] = P[3][14] + P[0][14]*SF[5] + P[1][14]*SF[4] + P[2][14]*SF[7] - P[11][14]*SF[11] + P[10][14]*SPP[7] - (P[12][14]*q0)/2;
+    nextP[3][15] = P[3][15] + P[0][15]*SF[5] + P[1][15]*SF[4] + P[2][15]*SF[7] - P[11][15]*SF[11] + P[10][15]*SPP[7] - (P[12][15]*q0)/2;
+    nextP[3][16] = P[3][16] + P[0][16]*SF[5] + P[1][16]*SF[4] + P[2][16]*SF[7] - P[11][16]*SF[11] + P[10][16]*SPP[7] - (P[12][16]*q0)/2;
+    nextP[3][17] = P[3][17] + P[0][17]*SF[5] + P[1][17]*SF[4] + P[2][17]*SF[7] - P[11][17]*SF[11] + P[10][17]*SPP[7] - (P[12][17]*q0)/2;
+    nextP[3][18] = P[3][18] + P[0][18]*SF[5] + P[1][18]*SF[4] + P[2][18]*SF[7] - P[11][18]*SF[11] + P[10][18]*SPP[7] - (P[12][18]*q0)/2;
+    nextP[3][19] = P[3][19] + P[0][19]*SF[5] + P[1][19]*SF[4] + P[2][19]*SF[7] - P[11][19]*SF[11] + P[10][19]*SPP[7] - (P[12][19]*q0)/2;
+    nextP[3][20] = P[3][20] + P[0][20]*SF[5] + P[1][20]*SF[4] + P[2][20]*SF[7] - P[11][20]*SF[11] + P[10][20]*SPP[7] - (P[12][20]*q0)/2;
+    nextP[3][21] = P[3][21] + P[0][21]*SF[5] + P[1][21]*SF[4] + P[2][21]*SF[7] - P[11][21]*SF[11] + P[10][21]*SPP[7] - (P[12][21]*q0)/2;
+    nextP[3][22] = P[3][22] + P[0][22]*SF[5] + P[1][22]*SF[4] + P[2][22]*SF[7] - P[11][22]*SF[11] + P[10][22]*SPP[7] - (P[12][22]*q0)/2;
+    nextP[4][0] = P[4][0] + P[0][0]*SF[3] + P[1][0]*SF[1] + P[2][0]*SPP[0] - P[3][0]*SPP[2] - P[13][0]*SPP[4] + SF[7]*(P[4][1] + P[0][1]*SF[3] + P[1][1]*SF[1] + P[2][1]*SPP[0] - P[3][1]*SPP[2] - P[13][1]*SPP[4]) + SF[9]*(P[4][2] + P[0][2]*SF[3] + P[1][2]*SF[1] + P[2][2]*SPP[0] - P[3][2]*SPP[2] - P[13][2]*SPP[4]) + SF[8]*(P[4][3] + P[0][3]*SF[3] + P[1][3]*SF[1] + P[2][3]*SPP[0] - P[3][3]*SPP[2] - P[13][3]*SPP[4]) + SF[11]*(P[4][10] + P[0][10]*SF[3] + P[1][10]*SF[1] + P[2][10]*SPP[0] - P[3][10]*SPP[2] - P[13][10]*SPP[4]) + SPP[7]*(P[4][11] + P[0][11]*SF[3] + P[1][11]*SF[1] + P[2][11]*SPP[0] - P[3][11]*SPP[2] - P[13][11]*SPP[4]) + SPP[6]*(P[4][12] + P[0][12]*SF[3] + P[1][12]*SF[1] + P[2][12]*SPP[0] - P[3][12]*SPP[2] - P[13][12]*SPP[4]);
+    nextP[4][1] = P[4][1] + P[0][1]*SF[3] + P[1][1]*SF[1] + P[2][1]*SPP[0] - P[3][1]*SPP[2] - P[13][1]*SPP[4] + SF[6]*(P[4][0] + P[0][0]*SF[3] + P[1][0]*SF[1] + P[2][0]*SPP[0] - P[3][0]*SPP[2] - P[13][0]*SPP[4]) + SF[5]*(P[4][2] + P[0][2]*SF[3] + P[1][2]*SF[1] + P[2][2]*SPP[0] - P[3][2]*SPP[2] - P[13][2]*SPP[4]) + SF[9]*(P[4][3] + P[0][3]*SF[3] + P[1][3]*SF[1] + P[2][3]*SPP[0] - P[3][3]*SPP[2] - P[13][3]*SPP[4]) + SPP[6]*(P[4][11] + P[0][11]*SF[3] + P[1][11]*SF[1] + P[2][11]*SPP[0] - P[3][11]*SPP[2] - P[13][11]*SPP[4]) - SPP[7]*(P[4][12] + P[0][12]*SF[3] + P[1][12]*SF[1] + P[2][12]*SPP[0] - P[3][12]*SPP[2] - P[13][12]*SPP[4]) - (q0*(P[4][10] + P[0][10]*SF[3] + P[1][10]*SF[1] + P[2][10]*SPP[0] - P[3][10]*SPP[2] - P[13][10]*SPP[4]))/2;
+    nextP[4][2] = P[4][2] + P[0][2]*SF[3] + P[1][2]*SF[1] + P[2][2]*SPP[0] - P[3][2]*SPP[2] - P[13][2]*SPP[4] + SF[4]*(P[4][0] + P[0][0]*SF[3] + P[1][0]*SF[1] + P[2][0]*SPP[0] - P[3][0]*SPP[2] - P[13][0]*SPP[4]) + SF[8]*(P[4][1] + P[0][1]*SF[3] + P[1][1]*SF[1] + P[2][1]*SPP[0] - P[3][1]*SPP[2] - P[13][1]*SPP[4]) + SF[6]*(P[4][3] + P[0][3]*SF[3] + P[1][3]*SF[1] + P[2][3]*SPP[0] - P[3][3]*SPP[2] - P[13][3]*SPP[4]) + SF[11]*(P[4][12] + P[0][12]*SF[3] + P[1][12]*SF[1] + P[2][12]*SPP[0] - P[3][12]*SPP[2] - P[13][12]*SPP[4]) - SPP[6]*(P[4][10] + P[0][10]*SF[3] + P[1][10]*SF[1] + P[2][10]*SPP[0] - P[3][10]*SPP[2] - P[13][10]*SPP[4]) - (q0*(P[4][11] + P[0][11]*SF[3] + P[1][11]*SF[1] + P[2][11]*SPP[0] - P[3][11]*SPP[2] - P[13][11]*SPP[4]))/2;
+    nextP[4][3] = P[4][3] + P[0][3]*SF[3] + P[1][3]*SF[1] + P[2][3]*SPP[0] - P[3][3]*SPP[2] - P[13][3]*SPP[4] + SF[5]*(P[4][0] + P[0][0]*SF[3] + P[1][0]*SF[1] + P[2][0]*SPP[0] - P[3][0]*SPP[2] - P[13][0]*SPP[4]) + SF[4]*(P[4][1] + P[0][1]*SF[3] + P[1][1]*SF[1] + P[2][1]*SPP[0] - P[3][1]*SPP[2] - P[13][1]*SPP[4]) + SF[7]*(P[4][2] + P[0][2]*SF[3] + P[1][2]*SF[1] + P[2][2]*SPP[0] - P[3][2]*SPP[2] - P[13][2]*SPP[4]) - SF[11]*(P[4][11] + P[0][11]*SF[3] + P[1][11]*SF[1] + P[2][11]*SPP[0] - P[3][11]*SPP[2] - P[13][11]*SPP[4]) + SPP[7]*(P[4][10] + P[0][10]*SF[3] + P[1][10]*SF[1] + P[2][10]*SPP[0] - P[3][10]*SPP[2] - P[13][10]*SPP[4]) - (q0*(P[4][12] + P[0][12]*SF[3] + P[1][12]*SF[1] + P[2][12]*SPP[0] - P[3][12]*SPP[2] - P[13][12]*SPP[4]))/2;
+    nextP[4][4] = P[4][4] + P[0][4]*SF[3] + P[1][4]*SF[1] + P[2][4]*SPP[0] - P[3][4]*SPP[2] - P[13][4]*SPP[4] + dvyCov*sq(SG[7] - 2*q0*q3) + dvzCov*sq(SG[6] + 2*q0*q2) + SF[3]*(P[4][0] + P[0][0]*SF[3] + P[1][0]*SF[1] + P[2][0]*SPP[0] - P[3][0]*SPP[2] - P[13][0]*SPP[4]) + SF[1]*(P[4][1] + P[0][1]*SF[3] + P[1][1]*SF[1] + P[2][1]*SPP[0] - P[3][1]*SPP[2] - P[13][1]*SPP[4]) + SPP[0]*(P[4][2] + P[0][2]*SF[3] + P[1][2]*SF[1] + P[2][2]*SPP[0] - P[3][2]*SPP[2] - P[13][2]*SPP[4]) - SPP[2]*(P[4][3] + P[0][3]*SF[3] + P[1][3]*SF[1] + P[2][3]*SPP[0] - P[3][3]*SPP[2] - P[13][3]*SPP[4]) - SPP[4]*(P[4][13] + P[0][13]*SF[3] + P[1][13]*SF[1] + P[2][13]*SPP[0] - P[3][13]*SPP[2] - P[13][13]*SPP[4]) + dvxCov*sq(SG[1] + SG[2] - SG[3] - SG[4]);
+    nextP[4][5] = P[4][5] + SQ[2] + P[0][5]*SF[3] + P[1][5]*SF[1] + P[2][5]*SPP[0] - P[3][5]*SPP[2] - P[13][5]*SPP[4] + SF[2]*(P[4][0] + P[0][0]*SF[3] + P[1][0]*SF[1] + P[2][0]*SPP[0] - P[3][0]*SPP[2] - P[13][0]*SPP[4]) + SF[1]*(P[4][2] + P[0][2]*SF[3] + P[1][2]*SF[1] + P[2][2]*SPP[0] - P[3][2]*SPP[2] - P[13][2]*SPP[4]) + SF[3]*(P[4][3] + P[0][3]*SF[3] + P[1][3]*SF[1] + P[2][3]*SPP[0] - P[3][3]*SPP[2] - P[13][3]*SPP[4]) - SPP[0]*(P[4][1] + P[0][1]*SF[3] + P[1][1]*SF[1] + P[2][1]*SPP[0] - P[3][1]*SPP[2] - P[13][1]*SPP[4]) + SPP[3]*(P[4][13] + P[0][13]*SF[3] + P[1][13]*SF[1] + P[2][13]*SPP[0] - P[3][13]*SPP[2] - P[13][13]*SPP[4]);
+    nextP[4][6] = P[4][6] + SQ[1] + P[0][6]*SF[3] + P[1][6]*SF[1] + P[2][6]*SPP[0] - P[3][6]*SPP[2] - P[13][6]*SPP[4] + SF[2]*(P[4][1] + P[0][1]*SF[3] + P[1][1]*SF[1] + P[2][1]*SPP[0] - P[3][1]*SPP[2] - P[13][1]*SPP[4]) + SF[1]*(P[4][3] + P[0][3]*SF[3] + P[1][3]*SF[1] + P[2][3]*SPP[0] - P[3][3]*SPP[2] - P[13][3]*SPP[4]) + SPP[0]*(P[4][0] + P[0][0]*SF[3] + P[1][0]*SF[1] + P[2][0]*SPP[0] - P[3][0]*SPP[2] - P[13][0]*SPP[4]) - SPP[1]*(P[4][2] + P[0][2]*SF[3] + P[1][2]*SF[1] + P[2][2]*SPP[0] - P[3][2]*SPP[2] - P[13][2]*SPP[4]) - (sq(q0) - sq(q1) - sq(q2) + sq(q3))*(P[4][13] + P[0][13]*SF[3] + P[1][13]*SF[1] + P[2][13]*SPP[0] - P[3][13]*SPP[2] - P[13][13]*SPP[4]);
+    nextP[4][7] = P[4][7] + P[0][7]*SF[3] + P[1][7]*SF[1] + P[2][7]*SPP[0] - P[3][7]*SPP[2] - P[13][7]*SPP[4] + dt*(P[4][4] + P[0][4]*SF[3] + P[1][4]*SF[1] + P[2][4]*SPP[0] - P[3][4]*SPP[2] - P[13][4]*SPP[4]);
+    nextP[4][8] = P[4][8] + P[0][8]*SF[3] + P[1][8]*SF[1] + P[2][8]*SPP[0] - P[3][8]*SPP[2] - P[13][8]*SPP[4] + dt*(P[4][5] + P[0][5]*SF[3] + P[1][5]*SF[1] + P[2][5]*SPP[0] - P[3][5]*SPP[2] - P[13][5]*SPP[4]);
+    nextP[4][9] = P[4][9] + P[0][9]*SF[3] + P[1][9]*SF[1] + P[2][9]*SPP[0] - P[3][9]*SPP[2] - P[13][9]*SPP[4] + dt*(P[4][6] + P[0][6]*SF[3] + P[1][6]*SF[1] + P[2][6]*SPP[0] - P[3][6]*SPP[2] - P[13][6]*SPP[4]);
+    nextP[4][10] = P[4][10] + P[0][10]*SF[3] + P[1][10]*SF[1] + P[2][10]*SPP[0] - P[3][10]*SPP[2] - P[13][10]*SPP[4];
+    nextP[4][11] = P[4][11] + P[0][11]*SF[3] + P[1][11]*SF[1] + P[2][11]*SPP[0] - P[3][11]*SPP[2] - P[13][11]*SPP[4];
+    nextP[4][12] = P[4][12] + P[0][12]*SF[3] + P[1][12]*SF[1] + P[2][12]*SPP[0] - P[3][12]*SPP[2] - P[13][12]*SPP[4];
+    nextP[4][13] = P[4][13] + P[0][13]*SF[3] + P[1][13]*SF[1] + P[2][13]*SPP[0] - P[3][13]*SPP[2] - P[13][13]*SPP[4];
+    nextP[4][14] = P[4][14] + P[0][14]*SF[3] + P[1][14]*SF[1] + P[2][14]*SPP[0] - P[3][14]*SPP[2] - P[13][14]*SPP[4];
+    nextP[4][15] = P[4][15] + P[0][15]*SF[3] + P[1][15]*SF[1] + P[2][15]*SPP[0] - P[3][15]*SPP[2] - P[13][15]*SPP[4];
+    nextP[4][16] = P[4][16] + P[0][16]*SF[3] + P[1][16]*SF[1] + P[2][16]*SPP[0] - P[3][16]*SPP[2] - P[13][16]*SPP[4];
+    nextP[4][17] = P[4][17] + P[0][17]*SF[3] + P[1][17]*SF[1] + P[2][17]*SPP[0] - P[3][17]*SPP[2] - P[13][17]*SPP[4];
+    nextP[4][18] = P[4][18] + P[0][18]*SF[3] + P[1][18]*SF[1] + P[2][18]*SPP[0] - P[3][18]*SPP[2] - P[13][18]*SPP[4];
+    nextP[4][19] = P[4][19] + P[0][19]*SF[3] + P[1][19]*SF[1] + P[2][19]*SPP[0] - P[3][19]*SPP[2] - P[13][19]*SPP[4];
+    nextP[4][20] = P[4][20] + P[0][20]*SF[3] + P[1][20]*SF[1] + P[2][20]*SPP[0] - P[3][20]*SPP[2] - P[13][20]*SPP[4];
+    nextP[4][21] = P[4][21] + P[0][21]*SF[3] + P[1][21]*SF[1] + P[2][21]*SPP[0] - P[3][21]*SPP[2] - P[13][21]*SPP[4];
+    nextP[4][22] = P[4][22] + P[0][22]*SF[3] + P[1][22]*SF[1] + P[2][22]*SPP[0] - P[3][22]*SPP[2] - P[13][22]*SPP[4];
+    nextP[5][0] = P[5][0] + P[0][0]*SF[2] + P[2][0]*SF[1] + P[3][0]*SF[3] - P[1][0]*SPP[0] + P[13][0]*SPP[3] + SF[7]*(P[5][1] + P[0][1]*SF[2] + P[2][1]*SF[1] + P[3][1]*SF[3] - P[1][1]*SPP[0] + P[13][1]*SPP[3]) + SF[9]*(P[5][2] + P[0][2]*SF[2] + P[2][2]*SF[1] + P[3][2]*SF[3] - P[1][2]*SPP[0] + P[13][2]*SPP[3]) + SF[8]*(P[5][3] + P[0][3]*SF[2] + P[2][3]*SF[1] + P[3][3]*SF[3] - P[1][3]*SPP[0] + P[13][3]*SPP[3]) + SF[11]*(P[5][10] + P[0][10]*SF[2] + P[2][10]*SF[1] + P[3][10]*SF[3] - P[1][10]*SPP[0] + P[13][10]*SPP[3]) + SPP[7]*(P[5][11] + P[0][11]*SF[2] + P[2][11]*SF[1] + P[3][11]*SF[3] - P[1][11]*SPP[0] + P[13][11]*SPP[3]) + SPP[6]*(P[5][12] + P[0][12]*SF[2] + P[2][12]*SF[1] + P[3][12]*SF[3] - P[1][12]*SPP[0] + P[13][12]*SPP[3]);
+    nextP[5][1] = P[5][1] + P[0][1]*SF[2] + P[2][1]*SF[1] + P[3][1]*SF[3] - P[1][1]*SPP[0] + P[13][1]*SPP[3] + SF[6]*(P[5][0] + P[0][0]*SF[2] + P[2][0]*SF[1] + P[3][0]*SF[3] - P[1][0]*SPP[0] + P[13][0]*SPP[3]) + SF[5]*(P[5][2] + P[0][2]*SF[2] + P[2][2]*SF[1] + P[3][2]*SF[3] - P[1][2]*SPP[0] + P[13][2]*SPP[3]) + SF[9]*(P[5][3] + P[0][3]*SF[2] + P[2][3]*SF[1] + P[3][3]*SF[3] - P[1][3]*SPP[0] + P[13][3]*SPP[3]) + SPP[6]*(P[5][11] + P[0][11]*SF[2] + P[2][11]*SF[1] + P[3][11]*SF[3] - P[1][11]*SPP[0] + P[13][11]*SPP[3]) - SPP[7]*(P[5][12] + P[0][12]*SF[2] + P[2][12]*SF[1] + P[3][12]*SF[3] - P[1][12]*SPP[0] + P[13][12]*SPP[3]) - (q0*(P[5][10] + P[0][10]*SF[2] + P[2][10]*SF[1] + P[3][10]*SF[3] - P[1][10]*SPP[0] + P[13][10]*SPP[3]))/2;
+    nextP[5][2] = P[5][2] + P[0][2]*SF[2] + P[2][2]*SF[1] + P[3][2]*SF[3] - P[1][2]*SPP[0] + P[13][2]*SPP[3] + SF[4]*(P[5][0] + P[0][0]*SF[2] + P[2][0]*SF[1] + P[3][0]*SF[3] - P[1][0]*SPP[0] + P[13][0]*SPP[3]) + SF[8]*(P[5][1] + P[0][1]*SF[2] + P[2][1]*SF[1] + P[3][1]*SF[3] - P[1][1]*SPP[0] + P[13][1]*SPP[3]) + SF[6]*(P[5][3] + P[0][3]*SF[2] + P[2][3]*SF[1] + P[3][3]*SF[3] - P[1][3]*SPP[0] + P[13][3]*SPP[3]) + SF[11]*(P[5][12] + P[0][12]*SF[2] + P[2][12]*SF[1] + P[3][12]*SF[3] - P[1][12]*SPP[0] + P[13][12]*SPP[3]) - SPP[6]*(P[5][10] + P[0][10]*SF[2] + P[2][10]*SF[1] + P[3][10]*SF[3] - P[1][10]*SPP[0] + P[13][10]*SPP[3]) - (q0*(P[5][11] + P[0][11]*SF[2] + P[2][11]*SF[1] + P[3][11]*SF[3] - P[1][11]*SPP[0] + P[13][11]*SPP[3]))/2;
+    nextP[5][3] = P[5][3] + P[0][3]*SF[2] + P[2][3]*SF[1] + P[3][3]*SF[3] - P[1][3]*SPP[0] + P[13][3]*SPP[3] + SF[5]*(P[5][0] + P[0][0]*SF[2] + P[2][0]*SF[1] + P[3][0]*SF[3] - P[1][0]*SPP[0] + P[13][0]*SPP[3]) + SF[4]*(P[5][1] + P[0][1]*SF[2] + P[2][1]*SF[1] + P[3][1]*SF[3] - P[1][1]*SPP[0] + P[13][1]*SPP[3]) + SF[7]*(P[5][2] + P[0][2]*SF[2] + P[2][2]*SF[1] + P[3][2]*SF[3] - P[1][2]*SPP[0] + P[13][2]*SPP[3]) - SF[11]*(P[5][11] + P[0][11]*SF[2] + P[2][11]*SF[1] + P[3][11]*SF[3] - P[1][11]*SPP[0] + P[13][11]*SPP[3]) + SPP[7]*(P[5][10] + P[0][10]*SF[2] + P[2][10]*SF[1] + P[3][10]*SF[3] - P[1][10]*SPP[0] + P[13][10]*SPP[3]) - (q0*(P[5][12] + P[0][12]*SF[2] + P[2][12]*SF[1] + P[3][12]*SF[3] - P[1][12]*SPP[0] + P[13][12]*SPP[3]))/2;
+    nextP[5][4] = P[5][4] + SQ[2] + P[0][4]*SF[2] + P[2][4]*SF[1] + P[3][4]*SF[3] - P[1][4]*SPP[0] + P[13][4]*SPP[3] + SF[3]*(P[5][0] + P[0][0]*SF[2] + P[2][0]*SF[1] + P[3][0]*SF[3] - P[1][0]*SPP[0] + P[13][0]*SPP[3]) + SF[1]*(P[5][1] + P[0][1]*SF[2] + P[2][1]*SF[1] + P[3][1]*SF[3] - P[1][1]*SPP[0] + P[13][1]*SPP[3]) + SPP[0]*(P[5][2] + P[0][2]*SF[2] + P[2][2]*SF[1] + P[3][2]*SF[3] - P[1][2]*SPP[0] + P[13][2]*SPP[3]) - SPP[2]*(P[5][3] + P[0][3]*SF[2] + P[2][3]*SF[1] + P[3][3]*SF[3] - P[1][3]*SPP[0] + P[13][3]*SPP[3]) - SPP[4]*(P[5][13] + P[0][13]*SF[2] + P[2][13]*SF[1] + P[3][13]*SF[3] - P[1][13]*SPP[0] + P[13][13]*SPP[3]);
+    nextP[5][5] = P[5][5] + P[0][5]*SF[2] + P[2][5]*SF[1] + P[3][5]*SF[3] - P[1][5]*SPP[0] + P[13][5]*SPP[3] + dvxCov*sq(SG[7] + 2*q0*q3) + dvzCov*sq(SG[5] - 2*q0*q1) + SF[2]*(P[5][0] + P[0][0]*SF[2] + P[2][0]*SF[1] + P[3][0]*SF[3] - P[1][0]*SPP[0] + P[13][0]*SPP[3]) + SF[1]*(P[5][2] + P[0][2]*SF[2] + P[2][2]*SF[1] + P[3][2]*SF[3] - P[1][2]*SPP[0] + P[13][2]*SPP[3]) + SF[3]*(P[5][3] + P[0][3]*SF[2] + P[2][3]*SF[1] + P[3][3]*SF[3] - P[1][3]*SPP[0] + P[13][3]*SPP[3]) - SPP[0]*(P[5][1] + P[0][1]*SF[2] + P[2][1]*SF[1] + P[3][1]*SF[3] - P[1][1]*SPP[0] + P[13][1]*SPP[3]) + SPP[3]*(P[5][13] + P[0][13]*SF[2] + P[2][13]*SF[1] + P[3][13]*SF[3] - P[1][13]*SPP[0] + P[13][13]*SPP[3]) + dvyCov*sq(SG[1] - SG[2] + SG[3] - SG[4]);
+    nextP[5][6] = P[5][6] + SQ[0] + P[0][6]*SF[2] + P[2][6]*SF[1] + P[3][6]*SF[3] - P[1][6]*SPP[0] + P[13][6]*SPP[3] + SF[2]*(P[5][1] + P[0][1]*SF[2] + P[2][1]*SF[1] + P[3][1]*SF[3] - P[1][1]*SPP[0] + P[13][1]*SPP[3]) + SF[1]*(P[5][3] + P[0][3]*SF[2] + P[2][3]*SF[1] + P[3][3]*SF[3] - P[1][3]*SPP[0] + P[13][3]*SPP[3]) + SPP[0]*(P[5][0] + P[0][0]*SF[2] + P[2][0]*SF[1] + P[3][0]*SF[3] - P[1][0]*SPP[0] + P[13][0]*SPP[3]) - SPP[1]*(P[5][2] + P[0][2]*SF[2] + P[2][2]*SF[1] + P[3][2]*SF[3] - P[1][2]*SPP[0] + P[13][2]*SPP[3]) - (sq(q0) - sq(q1) - sq(q2) + sq(q3))*(P[5][13] + P[0][13]*SF[2] + P[2][13]*SF[1] + P[3][13]*SF[3] - P[1][13]*SPP[0] + P[13][13]*SPP[3]);
+    nextP[5][7] = P[5][7] + P[0][7]*SF[2] + P[2][7]*SF[1] + P[3][7]*SF[3] - P[1][7]*SPP[0] + P[13][7]*SPP[3] + dt*(P[5][4] + P[0][4]*SF[2] + P[2][4]*SF[1] + P[3][4]*SF[3] - P[1][4]*SPP[0] + P[13][4]*SPP[3]);
+    nextP[5][8] = P[5][8] + P[0][8]*SF[2] + P[2][8]*SF[1] + P[3][8]*SF[3] - P[1][8]*SPP[0] + P[13][8]*SPP[3] + dt*(P[5][5] + P[0][5]*SF[2] + P[2][5]*SF[1] + P[3][5]*SF[3] - P[1][5]*SPP[0] + P[13][5]*SPP[3]);
+    nextP[5][9] = P[5][9] + P[0][9]*SF[2] + P[2][9]*SF[1] + P[3][9]*SF[3] - P[1][9]*SPP[0] + P[13][9]*SPP[3] + dt*(P[5][6] + P[0][6]*SF[2] + P[2][6]*SF[1] + P[3][6]*SF[3] - P[1][6]*SPP[0] + P[13][6]*SPP[3]);
+    nextP[5][10] = P[5][10] + P[0][10]*SF[2] + P[2][10]*SF[1] + P[3][10]*SF[3] - P[1][10]*SPP[0] + P[13][10]*SPP[3];
+    nextP[5][11] = P[5][11] + P[0][11]*SF[2] + P[2][11]*SF[1] + P[3][11]*SF[3] - P[1][11]*SPP[0] + P[13][11]*SPP[3];
+    nextP[5][12] = P[5][12] + P[0][12]*SF[2] + P[2][12]*SF[1] + P[3][12]*SF[3] - P[1][12]*SPP[0] + P[13][12]*SPP[3];
+    nextP[5][13] = P[5][13] + P[0][13]*SF[2] + P[2][13]*SF[1] + P[3][13]*SF[3] - P[1][13]*SPP[0] + P[13][13]*SPP[3];
+    nextP[5][14] = P[5][14] + P[0][14]*SF[2] + P[2][14]*SF[1] + P[3][14]*SF[3] - P[1][14]*SPP[0] + P[13][14]*SPP[3];
+    nextP[5][15] = P[5][15] + P[0][15]*SF[2] + P[2][15]*SF[1] + P[3][15]*SF[3] - P[1][15]*SPP[0] + P[13][15]*SPP[3];
+    nextP[5][16] = P[5][16] + P[0][16]*SF[2] + P[2][16]*SF[1] + P[3][16]*SF[3] - P[1][16]*SPP[0] + P[13][16]*SPP[3];
+    nextP[5][17] = P[5][17] + P[0][17]*SF[2] + P[2][17]*SF[1] + P[3][17]*SF[3] - P[1][17]*SPP[0] + P[13][17]*SPP[3];
+    nextP[5][18] = P[5][18] + P[0][18]*SF[2] + P[2][18]*SF[1] + P[3][18]*SF[3] - P[1][18]*SPP[0] + P[13][18]*SPP[3];
+    nextP[5][19] = P[5][19] + P[0][19]*SF[2] + P[2][19]*SF[1] + P[3][19]*SF[3] - P[1][19]*SPP[0] + P[13][19]*SPP[3];
+    nextP[5][20] = P[5][20] + P[0][20]*SF[2] + P[2][20]*SF[1] + P[3][20]*SF[3] - P[1][20]*SPP[0] + P[13][20]*SPP[3];
+    nextP[5][21] = P[5][21] + P[0][21]*SF[2] + P[2][21]*SF[1] + P[3][21]*SF[3] - P[1][21]*SPP[0] + P[13][21]*SPP[3];
+    nextP[5][22] = P[5][22] + P[0][22]*SF[2] + P[2][22]*SF[1] + P[3][22]*SF[3] - P[1][22]*SPP[0] + P[13][22]*SPP[3];
+    nextP[6][0] = P[6][0] + P[1][0]*SF[2] + P[3][0]*SF[1] + P[0][0]*SPP[0] - P[2][0]*SPP[1] - P[13][0]*(sq(q0) - sq(q1) - sq(q2) + sq(q3)) + SF[7]*(P[6][1] + P[1][1]*SF[2] + P[3][1]*SF[1] + P[0][1]*SPP[0] - P[2][1]*SPP[1] - P[13][1]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[9]*(P[6][2] + P[1][2]*SF[2] + P[3][2]*SF[1] + P[0][2]*SPP[0] - P[2][2]*SPP[1] - P[13][2]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[8]*(P[6][3] + P[1][3]*SF[2] + P[3][3]*SF[1] + P[0][3]*SPP[0] - P[2][3]*SPP[1] - P[13][3]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[11]*(P[6][10] + P[1][10]*SF[2] + P[3][10]*SF[1] + P[0][10]*SPP[0] - P[2][10]*SPP[1] - P[13][10]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SPP[7]*(P[6][11] + P[1][11]*SF[2] + P[3][11]*SF[1] + P[0][11]*SPP[0] - P[2][11]*SPP[1] - P[13][11]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SPP[6]*(P[6][12] + P[1][12]*SF[2] + P[3][12]*SF[1] + P[0][12]*SPP[0] - P[2][12]*SPP[1] - P[13][12]*(sq(q0) - sq(q1) - sq(q2) + sq(q3)));
+    nextP[6][1] = P[6][1] + P[1][1]*SF[2] + P[3][1]*SF[1] + P[0][1]*SPP[0] - P[2][1]*SPP[1] - P[13][1]*(sq(q0) - sq(q1) - sq(q2) + sq(q3)) + SF[6]*(P[6][0] + P[1][0]*SF[2] + P[3][0]*SF[1] + P[0][0]*SPP[0] - P[2][0]*SPP[1] - P[13][0]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[5]*(P[6][2] + P[1][2]*SF[2] + P[3][2]*SF[1] + P[0][2]*SPP[0] - P[2][2]*SPP[1] - P[13][2]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[9]*(P[6][3] + P[1][3]*SF[2] + P[3][3]*SF[1] + P[0][3]*SPP[0] - P[2][3]*SPP[1] - P[13][3]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SPP[6]*(P[6][11] + P[1][11]*SF[2] + P[3][11]*SF[1] + P[0][11]*SPP[0] - P[2][11]*SPP[1] - P[13][11]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) - SPP[7]*(P[6][12] + P[1][12]*SF[2] + P[3][12]*SF[1] + P[0][12]*SPP[0] - P[2][12]*SPP[1] - P[13][12]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) - (q0*(P[6][10] + P[1][10]*SF[2] + P[3][10]*SF[1] + P[0][10]*SPP[0] - P[2][10]*SPP[1] - P[13][10]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))))/2;
+    nextP[6][2] = P[6][2] + P[1][2]*SF[2] + P[3][2]*SF[1] + P[0][2]*SPP[0] - P[2][2]*SPP[1] - P[13][2]*(sq(q0) - sq(q1) - sq(q2) + sq(q3)) + SF[4]*(P[6][0] + P[1][0]*SF[2] + P[3][0]*SF[1] + P[0][0]*SPP[0] - P[2][0]*SPP[1] - P[13][0]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[8]*(P[6][1] + P[1][1]*SF[2] + P[3][1]*SF[1] + P[0][1]*SPP[0] - P[2][1]*SPP[1] - P[13][1]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[6]*(P[6][3] + P[1][3]*SF[2] + P[3][3]*SF[1] + P[0][3]*SPP[0] - P[2][3]*SPP[1] - P[13][3]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[11]*(P[6][12] + P[1][12]*SF[2] + P[3][12]*SF[1] + P[0][12]*SPP[0] - P[2][12]*SPP[1] - P[13][12]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) - SPP[6]*(P[6][10] + P[1][10]*SF[2] + P[3][10]*SF[1] + P[0][10]*SPP[0] - P[2][10]*SPP[1] - P[13][10]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) - (q0*(P[6][11] + P[1][11]*SF[2] + P[3][11]*SF[1] + P[0][11]*SPP[0] - P[2][11]*SPP[1] - P[13][11]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))))/2;
+    nextP[6][3] = P[6][3] + P[1][3]*SF[2] + P[3][3]*SF[1] + P[0][3]*SPP[0] - P[2][3]*SPP[1] - P[13][3]*(sq(q0) - sq(q1) - sq(q2) + sq(q3)) + SF[5]*(P[6][0] + P[1][0]*SF[2] + P[3][0]*SF[1] + P[0][0]*SPP[0] - P[2][0]*SPP[1] - P[13][0]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[4]*(P[6][1] + P[1][1]*SF[2] + P[3][1]*SF[1] + P[0][1]*SPP[0] - P[2][1]*SPP[1] - P[13][1]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[7]*(P[6][2] + P[1][2]*SF[2] + P[3][2]*SF[1] + P[0][2]*SPP[0] - P[2][2]*SPP[1] - P[13][2]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) - SF[11]*(P[6][11] + P[1][11]*SF[2] + P[3][11]*SF[1] + P[0][11]*SPP[0] - P[2][11]*SPP[1] - P[13][11]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SPP[7]*(P[6][10] + P[1][10]*SF[2] + P[3][10]*SF[1] + P[0][10]*SPP[0] - P[2][10]*SPP[1] - P[13][10]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) - (q0*(P[6][12] + P[1][12]*SF[2] + P[3][12]*SF[1] + P[0][12]*SPP[0] - P[2][12]*SPP[1] - P[13][12]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))))/2;
+    nextP[6][4] = P[6][4] + SQ[1] + P[1][4]*SF[2] + P[3][4]*SF[1] + P[0][4]*SPP[0] - P[2][4]*SPP[1] - P[13][4]*(sq(q0) - sq(q1) - sq(q2) + sq(q3)) + SF[3]*(P[6][0] + P[1][0]*SF[2] + P[3][0]*SF[1] + P[0][0]*SPP[0] - P[2][0]*SPP[1] - P[13][0]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[1]*(P[6][1] + P[1][1]*SF[2] + P[3][1]*SF[1] + P[0][1]*SPP[0] - P[2][1]*SPP[1] - P[13][1]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SPP[0]*(P[6][2] + P[1][2]*SF[2] + P[3][2]*SF[1] + P[0][2]*SPP[0] - P[2][2]*SPP[1] - P[13][2]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) - SPP[2]*(P[6][3] + P[1][3]*SF[2] + P[3][3]*SF[1] + P[0][3]*SPP[0] - P[2][3]*SPP[1] - P[13][3]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) - SPP[4]*(P[6][13] + P[1][13]*SF[2] + P[3][13]*SF[1] + P[0][13]*SPP[0] - P[2][13]*SPP[1] - P[13][13]*(sq(q0) - sq(q1) - sq(q2) + sq(q3)));
+    nextP[6][5] = P[6][5] + SQ[0] + P[1][5]*SF[2] + P[3][5]*SF[1] + P[0][5]*SPP[0] - P[2][5]*SPP[1] - P[13][5]*(sq(q0) - sq(q1) - sq(q2) + sq(q3)) + SF[2]*(P[6][0] + P[1][0]*SF[2] + P[3][0]*SF[1] + P[0][0]*SPP[0] - P[2][0]*SPP[1] - P[13][0]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[1]*(P[6][2] + P[1][2]*SF[2] + P[3][2]*SF[1] + P[0][2]*SPP[0] - P[2][2]*SPP[1] - P[13][2]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[3]*(P[6][3] + P[1][3]*SF[2] + P[3][3]*SF[1] + P[0][3]*SPP[0] - P[2][3]*SPP[1] - P[13][3]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) - SPP[0]*(P[6][1] + P[1][1]*SF[2] + P[3][1]*SF[1] + P[0][1]*SPP[0] - P[2][1]*SPP[1] - P[13][1]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SPP[3]*(P[6][13] + P[1][13]*SF[2] + P[3][13]*SF[1] + P[0][13]*SPP[0] - P[2][13]*SPP[1] - P[13][13]*(sq(q0) - sq(q1) - sq(q2) + sq(q3)));
+    nextP[6][6] = P[6][6] + P[1][6]*SF[2] + P[3][6]*SF[1] + P[0][6]*SPP[0] - P[2][6]*SPP[1] - P[13][6]*(sq(q0) - sq(q1) - sq(q2) + sq(q3)) + dvxCov*sq(SG[6] - 2*q0*q2) + dvyCov*sq(SG[5] + 2*q0*q1) - SPP[5]*(P[6][13] + P[1][13]*SF[2] + P[3][13]*SF[1] + P[0][13]*SPP[0] - P[2][13]*SPP[1] - P[13][13]*SPP[5]) + SF[2]*(P[6][1] + P[1][1]*SF[2] + P[3][1]*SF[1] + P[0][1]*SPP[0] - P[2][1]*SPP[1] - P[13][1]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SF[1]*(P[6][3] + P[1][3]*SF[2] + P[3][3]*SF[1] + P[0][3]*SPP[0] - P[2][3]*SPP[1] - P[13][3]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + SPP[0]*(P[6][0] + P[1][0]*SF[2] + P[3][0]*SF[1] + P[0][0]*SPP[0] - P[2][0]*SPP[1] - P[13][0]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) - SPP[1]*(P[6][2] + P[1][2]*SF[2] + P[3][2]*SF[1] + P[0][2]*SPP[0] - P[2][2]*SPP[1] - P[13][2]*(sq(q0) - sq(q1) - sq(q2) + sq(q3))) + dvzCov*sq(SG[1] - SG[2] - SG[3] + SG[4]);
+    nextP[6][7] = P[6][7] + P[1][7]*SF[2] + P[3][7]*SF[1] + P[0][7]*SPP[0] - P[2][7]*SPP[1] - P[13][7]*SPP[5] + dt*(P[6][4] + P[1][4]*SF[2] + P[3][4]*SF[1] + P[0][4]*SPP[0] - P[2][4]*SPP[1] - P[13][4]*SPP[5]);
+    nextP[6][8] = P[6][8] + P[1][8]*SF[2] + P[3][8]*SF[1] + P[0][8]*SPP[0] - P[2][8]*SPP[1] - P[13][8]*SPP[5] + dt*(P[6][5] + P[1][5]*SF[2] + P[3][5]*SF[1] + P[0][5]*SPP[0] - P[2][5]*SPP[1] - P[13][5]*SPP[5]);
+    nextP[6][9] = P[6][9] + P[1][9]*SF[2] + P[3][9]*SF[1] + P[0][9]*SPP[0] - P[2][9]*SPP[1] - P[13][9]*SPP[5] + dt*(P[6][6] + P[1][6]*SF[2] + P[3][6]*SF[1] + P[0][6]*SPP[0] - P[2][6]*SPP[1] - P[13][6]*SPP[5]);
+    nextP[6][10] = P[6][10] + P[1][10]*SF[2] + P[3][10]*SF[1] + P[0][10]*SPP[0] - P[2][10]*SPP[1] - P[13][10]*SPP[5];
+    nextP[6][11] = P[6][11] + P[1][11]*SF[2] + P[3][11]*SF[1] + P[0][11]*SPP[0] - P[2][11]*SPP[1] - P[13][11]*SPP[5];
+    nextP[6][12] = P[6][12] + P[1][12]*SF[2] + P[3][12]*SF[1] + P[0][12]*SPP[0] - P[2][12]*SPP[1] - P[13][12]*SPP[5];
+    nextP[6][13] = P[6][13] + P[1][13]*SF[2] + P[3][13]*SF[1] + P[0][13]*SPP[0] - P[2][13]*SPP[1] - P[13][13]*SPP[5];
+    nextP[6][14] = P[6][14] + P[1][14]*SF[2] + P[3][14]*SF[1] + P[0][14]*SPP[0] - P[2][14]*SPP[1] - P[13][14]*SPP[5];
+    nextP[6][15] = P[6][15] + P[1][15]*SF[2] + P[3][15]*SF[1] + P[0][15]*SPP[0] - P[2][15]*SPP[1] - P[13][15]*SPP[5];
+    nextP[6][16] = P[6][16] + P[1][16]*SF[2] + P[3][16]*SF[1] + P[0][16]*SPP[0] - P[2][16]*SPP[1] - P[13][16]*SPP[5];
+    nextP[6][17] = P[6][17] + P[1][17]*SF[2] + P[3][17]*SF[1] + P[0][17]*SPP[0] - P[2][17]*SPP[1] - P[13][17]*SPP[5];
+    nextP[6][18] = P[6][18] + P[1][18]*SF[2] + P[3][18]*SF[1] + P[0][18]*SPP[0] - P[2][18]*SPP[1] - P[13][18]*SPP[5];
+    nextP[6][19] = P[6][19] + P[1][19]*SF[2] + P[3][19]*SF[1] + P[0][19]*SPP[0] - P[2][19]*SPP[1] - P[13][19]*SPP[5];
+    nextP[6][20] = P[6][20] + P[1][20]*SF[2] + P[3][20]*SF[1] + P[0][20]*SPP[0] - P[2][20]*SPP[1] - P[13][20]*SPP[5];
+    nextP[6][21] = P[6][21] + P[1][21]*SF[2] + P[3][21]*SF[1] + P[0][21]*SPP[0] - P[2][21]*SPP[1] - P[13][21]*SPP[5];
+    nextP[6][22] = P[6][22] + P[1][22]*SF[2] + P[3][22]*SF[1] + P[0][22]*SPP[0] - P[2][22]*SPP[1] - P[13][22]*SPP[5];
+    nextP[7][0] = P[7][0] + P[4][0]*dt + SF[7]*(P[7][1] + P[4][1]*dt) + SF[9]*(P[7][2] + P[4][2]*dt) + SF[8]*(P[7][3] + P[4][3]*dt) + SF[11]*(P[7][10] + P[4][10]*dt) + SPP[7]*(P[7][11] + P[4][11]*dt) + SPP[6]*(P[7][12] + P[4][12]*dt);
+    nextP[7][1] = P[7][1] + P[4][1]*dt + SF[6]*(P[7][0] + P[4][0]*dt) + SF[5]*(P[7][2] + P[4][2]*dt) + SF[9]*(P[7][3] + P[4][3]*dt) + SPP[6]*(P[7][11] + P[4][11]*dt) - SPP[7]*(P[7][12] + P[4][12]*dt) - (q0*(P[7][10] + P[4][10]*dt))/2;
+    nextP[7][2] = P[7][2] + P[4][2]*dt + SF[4]*(P[7][0] + P[4][0]*dt) + SF[8]*(P[7][1] + P[4][1]*dt) + SF[6]*(P[7][3] + P[4][3]*dt) + SF[11]*(P[7][12] + P[4][12]*dt) - SPP[6]*(P[7][10] + P[4][10]*dt) - (q0*(P[7][11] + P[4][11]*dt))/2;
+    nextP[7][3] = P[7][3] + P[4][3]*dt + SF[5]*(P[7][0] + P[4][0]*dt) + SF[4]*(P[7][1] + P[4][1]*dt) + SF[7]*(P[7][2] + P[4][2]*dt) - SF[11]*(P[7][11] + P[4][11]*dt) + SPP[7]*(P[7][10] + P[4][10]*dt) - (q0*(P[7][12] + P[4][12]*dt))/2;
+    nextP[7][4] = P[7][4] + P[4][4]*dt + SF[1]*(P[7][1] + P[4][1]*dt) + SF[3]*(P[7][0] + P[4][0]*dt) + SPP[0]*(P[7][2] + P[4][2]*dt) - SPP[2]*(P[7][3] + P[4][3]*dt) - SPP[4]*(P[7][13] + P[4][13]*dt);
+    nextP[7][5] = P[7][5] + P[4][5]*dt + SF[2]*(P[7][0] + P[4][0]*dt) + SF[1]*(P[7][2] + P[4][2]*dt) + SF[3]*(P[7][3] + P[4][3]*dt) - SPP[0]*(P[7][1] + P[4][1]*dt) + SPP[3]*(P[7][13] + P[4][13]*dt);
+    nextP[7][6] = P[7][6] + P[4][6]*dt + SF[2]*(P[7][1] + P[4][1]*dt) + SF[1]*(P[7][3] + P[4][3]*dt) + SPP[0]*(P[7][0] + P[4][0]*dt) - SPP[1]*(P[7][2] + P[4][2]*dt) - SPP[5]*(P[7][13] + P[4][13]*dt);
+    nextP[7][7] = P[7][7] + P[4][7]*dt + dt*(P[7][4] + P[4][4]*dt);
+    nextP[7][8] = P[7][8] + P[4][8]*dt + dt*(P[7][5] + P[4][5]*dt);
+    nextP[7][9] = P[7][9] + P[4][9]*dt + dt*(P[7][6] + P[4][6]*dt);
+    nextP[7][10] = P[7][10] + P[4][10]*dt;
+    nextP[7][11] = P[7][11] + P[4][11]*dt;
+    nextP[7][12] = P[7][12] + P[4][12]*dt;
+    nextP[7][13] = P[7][13] + P[4][13]*dt;
+    nextP[7][14] = P[7][14] + P[4][14]*dt;
+    nextP[7][15] = P[7][15] + P[4][15]*dt;
+    nextP[7][16] = P[7][16] + P[4][16]*dt;
+    nextP[7][17] = P[7][17] + P[4][17]*dt;
+    nextP[7][18] = P[7][18] + P[4][18]*dt;
+    nextP[7][19] = P[7][19] + P[4][19]*dt;
+    nextP[7][20] = P[7][20] + P[4][20]*dt;
+    nextP[7][21] = P[7][21] + P[4][21]*dt;
+    nextP[7][22] = P[7][22] + P[4][22]*dt;
+    nextP[8][0] = P[8][0] + P[5][0]*dt + SF[7]*(P[8][1] + P[5][1]*dt) + SF[9]*(P[8][2] + P[5][2]*dt) + SF[8]*(P[8][3] + P[5][3]*dt) + SF[11]*(P[8][10] + P[5][10]*dt) + SPP[7]*(P[8][11] + P[5][11]*dt) + SPP[6]*(P[8][12] + P[5][12]*dt);
+    nextP[8][1] = P[8][1] + P[5][1]*dt + SF[6]*(P[8][0] + P[5][0]*dt) + SF[5]*(P[8][2] + P[5][2]*dt) + SF[9]*(P[8][3] + P[5][3]*dt) + SPP[6]*(P[8][11] + P[5][11]*dt) - SPP[7]*(P[8][12] + P[5][12]*dt) - (q0*(P[8][10] + P[5][10]*dt))/2;
+    nextP[8][2] = P[8][2] + P[5][2]*dt + SF[4]*(P[8][0] + P[5][0]*dt) + SF[8]*(P[8][1] + P[5][1]*dt) + SF[6]*(P[8][3] + P[5][3]*dt) + SF[11]*(P[8][12] + P[5][12]*dt) - SPP[6]*(P[8][10] + P[5][10]*dt) - (q0*(P[8][11] + P[5][11]*dt))/2;
+    nextP[8][3] = P[8][3] + P[5][3]*dt + SF[5]*(P[8][0] + P[5][0]*dt) + SF[4]*(P[8][1] + P[5][1]*dt) + SF[7]*(P[8][2] + P[5][2]*dt) - SF[11]*(P[8][11] + P[5][11]*dt) + SPP[7]*(P[8][10] + P[5][10]*dt) - (q0*(P[8][12] + P[5][12]*dt))/2;
+    nextP[8][4] = P[8][4] + P[5][4]*dt + SF[1]*(P[8][1] + P[5][1]*dt) + SF[3]*(P[8][0] + P[5][0]*dt) + SPP[0]*(P[8][2] + P[5][2]*dt) - SPP[2]*(P[8][3] + P[5][3]*dt) - SPP[4]*(P[8][13] + P[5][13]*dt);
+    nextP[8][5] = P[8][5] + P[5][5]*dt + SF[2]*(P[8][0] + P[5][0]*dt) + SF[1]*(P[8][2] + P[5][2]*dt) + SF[3]*(P[8][3] + P[5][3]*dt) - SPP[0]*(P[8][1] + P[5][1]*dt) + SPP[3]*(P[8][13] + P[5][13]*dt);
+    nextP[8][6] = P[8][6] + P[5][6]*dt + SF[2]*(P[8][1] + P[5][1]*dt) + SF[1]*(P[8][3] + P[5][3]*dt) + SPP[0]*(P[8][0] + P[5][0]*dt) - SPP[1]*(P[8][2] + P[5][2]*dt) - SPP[5]*(P[8][13] + P[5][13]*dt);
+    nextP[8][7] = P[8][7] + P[5][7]*dt + dt*(P[8][4] + P[5][4]*dt);
+    nextP[8][8] = P[8][8] + P[5][8]*dt + dt*(P[8][5] + P[5][5]*dt);
+    nextP[8][9] = P[8][9] + P[5][9]*dt + dt*(P[8][6] + P[5][6]*dt);
+    nextP[8][10] = P[8][10] + P[5][10]*dt;
+    nextP[8][11] = P[8][11] + P[5][11]*dt;
+    nextP[8][12] = P[8][12] + P[5][12]*dt;
+    nextP[8][13] = P[8][13] + P[5][13]*dt;
+    nextP[8][14] = P[8][14] + P[5][14]*dt;
+    nextP[8][15] = P[8][15] + P[5][15]*dt;
+    nextP[8][16] = P[8][16] + P[5][16]*dt;
+    nextP[8][17] = P[8][17] + P[5][17]*dt;
+    nextP[8][18] = P[8][18] + P[5][18]*dt;
+    nextP[8][19] = P[8][19] + P[5][19]*dt;
+    nextP[8][20] = P[8][20] + P[5][20]*dt;
+    nextP[8][21] = P[8][21] + P[5][21]*dt;
+    nextP[8][22] = P[8][22] + P[5][22]*dt;
+    nextP[9][0] = P[9][0] + P[6][0]*dt + SF[7]*(P[9][1] + P[6][1]*dt) + SF[9]*(P[9][2] + P[6][2]*dt) + SF[8]*(P[9][3] + P[6][3]*dt) + SF[11]*(P[9][10] + P[6][10]*dt) + SPP[7]*(P[9][11] + P[6][11]*dt) + SPP[6]*(P[9][12] + P[6][12]*dt);
+    nextP[9][1] = P[9][1] + P[6][1]*dt + SF[6]*(P[9][0] + P[6][0]*dt) + SF[5]*(P[9][2] + P[6][2]*dt) + SF[9]*(P[9][3] + P[6][3]*dt) + SPP[6]*(P[9][11] + P[6][11]*dt) - SPP[7]*(P[9][12] + P[6][12]*dt) - (q0*(P[9][10] + P[6][10]*dt))/2;
+    nextP[9][2] = P[9][2] + P[6][2]*dt + SF[4]*(P[9][0] + P[6][0]*dt) + SF[8]*(P[9][1] + P[6][1]*dt) + SF[6]*(P[9][3] + P[6][3]*dt) + SF[11]*(P[9][12] + P[6][12]*dt) - SPP[6]*(P[9][10] + P[6][10]*dt) - (q0*(P[9][11] + P[6][11]*dt))/2;
+    nextP[9][3] = P[9][3] + P[6][3]*dt + SF[5]*(P[9][0] + P[6][0]*dt) + SF[4]*(P[9][1] + P[6][1]*dt) + SF[7]*(P[9][2] + P[6][2]*dt) - SF[11]*(P[9][11] + P[6][11]*dt) + SPP[7]*(P[9][10] + P[6][10]*dt) - (q0*(P[9][12] + P[6][12]*dt))/2;
+    nextP[9][4] = P[9][4] + P[6][4]*dt + SF[1]*(P[9][1] + P[6][1]*dt) + SF[3]*(P[9][0] + P[6][0]*dt) + SPP[0]*(P[9][2] + P[6][2]*dt) - SPP[2]*(P[9][3] + P[6][3]*dt) - SPP[4]*(P[9][13] + P[6][13]*dt);
+    nextP[9][5] = P[9][5] + P[6][5]*dt + SF[2]*(P[9][0] + P[6][0]*dt) + SF[1]*(P[9][2] + P[6][2]*dt) + SF[3]*(P[9][3] + P[6][3]*dt) - SPP[0]*(P[9][1] + P[6][1]*dt) + SPP[3]*(P[9][13] + P[6][13]*dt);
+    nextP[9][6] = P[9][6] + P[6][6]*dt + SF[2]*(P[9][1] + P[6][1]*dt) + SF[1]*(P[9][3] + P[6][3]*dt) + SPP[0]*(P[9][0] + P[6][0]*dt) - SPP[1]*(P[9][2] + P[6][2]*dt) - SPP[5]*(P[9][13] + P[6][13]*dt);
+    nextP[9][7] = P[9][7] + P[6][7]*dt + dt*(P[9][4] + P[6][4]*dt);
+    nextP[9][8] = P[9][8] + P[6][8]*dt + dt*(P[9][5] + P[6][5]*dt);
+    nextP[9][9] = P[9][9] + P[6][9]*dt + dt*(P[9][6] + P[6][6]*dt);
+    nextP[9][10] = P[9][10] + P[6][10]*dt;
+    nextP[9][11] = P[9][11] + P[6][11]*dt;
+    nextP[9][12] = P[9][12] + P[6][12]*dt;
+    nextP[9][13] = P[9][13] + P[6][13]*dt;
+    nextP[9][14] = P[9][14] + P[6][14]*dt;
+    nextP[9][15] = P[9][15] + P[6][15]*dt;
+    nextP[9][16] = P[9][16] + P[6][16]*dt;
+    nextP[9][17] = P[9][17] + P[6][17]*dt;
+    nextP[9][18] = P[9][18] + P[6][18]*dt;
+    nextP[9][19] = P[9][19] + P[6][19]*dt;
+    nextP[9][20] = P[9][20] + P[6][20]*dt;
+    nextP[9][21] = P[9][21] + P[6][21]*dt;
+    nextP[9][22] = P[9][22] + P[6][22]*dt;
+    nextP[10][0] = P[10][0] + P[10][1]*SF[7] + P[10][2]*SF[9] + P[10][3]*SF[8] + P[10][10]*SF[11] + P[10][11]*SPP[7] + P[10][12]*SPP[6];
+    nextP[10][1] = P[10][1] + P[10][0]*SF[6] + P[10][2]*SF[5] + P[10][3]*SF[9] + P[10][11]*SPP[6] - P[10][12]*SPP[7] - (P[10][10]*q0)/2;
+    nextP[10][2] = P[10][2] + P[10][0]*SF[4] + P[10][1]*SF[8] + P[10][3]*SF[6] + P[10][12]*SF[11] - P[10][10]*SPP[6] - (P[10][11]*q0)/2;
+    nextP[10][3] = P[10][3] + P[10][0]*SF[5] + P[10][1]*SF[4] + P[10][2]*SF[7] - P[10][11]*SF[11] + P[10][10]*SPP[7] - (P[10][12]*q0)/2;
+    nextP[10][4] = P[10][4] + P[10][1]*SF[1] + P[10][0]*SF[3] + P[10][2]*SPP[0] - P[10][3]*SPP[2] - P[10][13]*SPP[4];
+    nextP[10][5] = P[10][5] + P[10][0]*SF[2] + P[10][2]*SF[1] + P[10][3]*SF[3] - P[10][1]*SPP[0] + P[10][13]*SPP[3];
+    nextP[10][6] = P[10][6] + P[10][1]*SF[2] + P[10][3]*SF[1] + P[10][0]*SPP[0] - P[10][2]*SPP[1] - P[10][13]*SPP[5];
+    nextP[10][7] = P[10][7] + P[10][4]*dt;
+    nextP[10][8] = P[10][8] + P[10][5]*dt;
+    nextP[10][9] = P[10][9] + P[10][6]*dt;
+    nextP[10][10] = P[10][10];
+    nextP[10][11] = P[10][11];
+    nextP[10][12] = P[10][12];
+    nextP[10][13] = P[10][13];
+    nextP[10][14] = P[10][14];
+    nextP[10][15] = P[10][15];
+    nextP[10][16] = P[10][16];
+    nextP[10][17] = P[10][17];
+    nextP[10][18] = P[10][18];
+    nextP[10][19] = P[10][19];
+    nextP[10][20] = P[10][20];
+    nextP[10][21] = P[10][21];
+    nextP[10][22] = P[10][22];
+    nextP[11][0] = P[11][0] + P[11][1]*SF[7] + P[11][2]*SF[9] + P[11][3]*SF[8] + P[11][10]*SF[11] + P[11][11]*SPP[7] + P[11][12]*SPP[6];
+    nextP[11][1] = P[11][1] + P[11][0]*SF[6] + P[11][2]*SF[5] + P[11][3]*SF[9] + P[11][11]*SPP[6] - P[11][12]*SPP[7] - (P[11][10]*q0)/2;
+    nextP[11][2] = P[11][2] + P[11][0]*SF[4] + P[11][1]*SF[8] + P[11][3]*SF[6] + P[11][12]*SF[11] - P[11][10]*SPP[6] - (P[11][11]*q0)/2;
+    nextP[11][3] = P[11][3] + P[11][0]*SF[5] + P[11][1]*SF[4] + P[11][2]*SF[7] - P[11][11]*SF[11] + P[11][10]*SPP[7] - (P[11][12]*q0)/2;
+    nextP[11][4] = P[11][4] + P[11][1]*SF[1] + P[11][0]*SF[3] + P[11][2]*SPP[0] - P[11][3]*SPP[2] - P[11][13]*SPP[4];
+    nextP[11][5] = P[11][5] + P[11][0]*SF[2] + P[11][2]*SF[1] + P[11][3]*SF[3] - P[11][1]*SPP[0] + P[11][13]*SPP[3];
+    nextP[11][6] = P[11][6] + P[11][1]*SF[2] + P[11][3]*SF[1] + P[11][0]*SPP[0] - P[11][2]*SPP[1] - P[11][13]*SPP[5];
+    nextP[11][7] = P[11][7] + P[11][4]*dt;
+    nextP[11][8] = P[11][8] + P[11][5]*dt;
+    nextP[11][9] = P[11][9] + P[11][6]*dt;
+    nextP[11][10] = P[11][10];
+    nextP[11][11] = P[11][11];
+    nextP[11][12] = P[11][12];
+    nextP[11][13] = P[11][13];
+    nextP[11][14] = P[11][14];
+    nextP[11][15] = P[11][15];
+    nextP[11][16] = P[11][16];
+    nextP[11][17] = P[11][17];
+    nextP[11][18] = P[11][18];
+    nextP[11][19] = P[11][19];
+    nextP[11][20] = P[11][20];
+    nextP[11][21] = P[11][21];
+    nextP[11][22] = P[11][22];
+    nextP[12][0] = P[12][0] + P[12][1]*SF[7] + P[12][2]*SF[9] + P[12][3]*SF[8] + P[12][10]*SF[11] + P[12][11]*SPP[7] + P[12][12]*SPP[6];
+    nextP[12][1] = P[12][1] + P[12][0]*SF[6] + P[12][2]*SF[5] + P[12][3]*SF[9] + P[12][11]*SPP[6] - P[12][12]*SPP[7] - (P[12][10]*q0)/2;
+    nextP[12][2] = P[12][2] + P[12][0]*SF[4] + P[12][1]*SF[8] + P[12][3]*SF[6] + P[12][12]*SF[11] - P[12][10]*SPP[6] - (P[12][11]*q0)/2;
+    nextP[12][3] = P[12][3] + P[12][0]*SF[5] + P[12][1]*SF[4] + P[12][2]*SF[7] - P[12][11]*SF[11] + P[12][10]*SPP[7] - (P[12][12]*q0)/2;
+    nextP[12][4] = P[12][4] + P[12][1]*SF[1] + P[12][0]*SF[3] + P[12][2]*SPP[0] - P[12][3]*SPP[2] - P[12][13]*SPP[4];
+    nextP[12][5] = P[12][5] + P[12][0]*SF[2] + P[12][2]*SF[1] + P[12][3]*SF[3] - P[12][1]*SPP[0] + P[12][13]*SPP[3];
+    nextP[12][6] = P[12][6] + P[12][1]*SF[2] + P[12][3]*SF[1] + P[12][0]*SPP[0] - P[12][2]*SPP[1] - P[12][13]*SPP[5];
+    nextP[12][7] = P[12][7] + P[12][4]*dt;
+    nextP[12][8] = P[12][8] + P[12][5]*dt;
+    nextP[12][9] = P[12][9] + P[12][6]*dt;
+    nextP[12][10] = P[12][10];
+    nextP[12][11] = P[12][11];
+    nextP[12][12] = P[12][12];
+    nextP[12][13] = P[12][13];
+    nextP[12][14] = P[12][14];
+    nextP[12][15] = P[12][15];
+    nextP[12][16] = P[12][16];
+    nextP[12][17] = P[12][17];
+    nextP[12][18] = P[12][18];
+    nextP[12][19] = P[12][19];
+    nextP[12][20] = P[12][20];
+    nextP[12][21] = P[12][21];
+    nextP[12][22] = P[12][22];
+    nextP[13][0] = P[13][0] + P[13][1]*SF[7] + P[13][2]*SF[9] + P[13][3]*SF[8] + P[13][10]*SF[11] + P[13][11]*SPP[7] + P[13][12]*SPP[6];
+    nextP[13][1] = P[13][1] + P[13][0]*SF[6] + P[13][2]*SF[5] + P[13][3]*SF[9] + P[13][11]*SPP[6] - P[13][12]*SPP[7] - (P[13][10]*q0)/2;
+    nextP[13][2] = P[13][2] + P[13][0]*SF[4] + P[13][1]*SF[8] + P[13][3]*SF[6] + P[13][12]*SF[11] - P[13][10]*SPP[6] - (P[13][11]*q0)/2;
+    nextP[13][3] = P[13][3] + P[13][0]*SF[5] + P[13][1]*SF[4] + P[13][2]*SF[7] - P[13][11]*SF[11] + P[13][10]*SPP[7] - (P[13][12]*q0)/2;
+    nextP[13][4] = P[13][4] + P[13][1]*SF[1] + P[13][0]*SF[3] + P[13][2]*SPP[0] - P[13][3]*SPP[2] - P[13][13]*SPP[4];
+    nextP[13][5] = P[13][5] + P[13][0]*SF[2] + P[13][2]*SF[1] + P[13][3]*SF[3] - P[13][1]*SPP[0] + P[13][13]*SPP[3];
+    nextP[13][6] = P[13][6] + P[13][1]*SF[2] + P[13][3]*SF[1] + P[13][0]*SPP[0] - P[13][2]*SPP[1] - P[13][13]*SPP[5];
+    nextP[13][7] = P[13][7] + P[13][4]*dt;
+    nextP[13][8] = P[13][8] + P[13][5]*dt;
+    nextP[13][9] = P[13][9] + P[13][6]*dt;
+    nextP[13][10] = P[13][10];
+    nextP[13][11] = P[13][11];
+    nextP[13][12] = P[13][12];
+    nextP[13][13] = P[13][13];
+    nextP[13][14] = P[13][14];
+    nextP[13][15] = P[13][15];
+    nextP[13][16] = P[13][16];
+    nextP[13][17] = P[13][17];
+    nextP[13][18] = P[13][18];
+    nextP[13][19] = P[13][19];
+    nextP[13][20] = P[13][20];
+    nextP[13][21] = P[13][21];
+    nextP[13][22] = P[13][22];
+    nextP[14][0] = P[14][0] + P[14][1]*SF[7] + P[14][2]*SF[9] + P[14][3]*SF[8] + P[14][10]*SF[11] + P[14][11]*SPP[7] + P[14][12]*SPP[6];
+    nextP[14][1] = P[14][1] + P[14][0]*SF[6] + P[14][2]*SF[5] + P[14][3]*SF[9] + P[14][11]*SPP[6] - P[14][12]*SPP[7] - (P[14][10]*q0)/2;
+    nextP[14][2] = P[14][2] + P[14][0]*SF[4] + P[14][1]*SF[8] + P[14][3]*SF[6] + P[14][12]*SF[11] - P[14][10]*SPP[6] - (P[14][11]*q0)/2;
+    nextP[14][3] = P[14][3] + P[14][0]*SF[5] + P[14][1]*SF[4] + P[14][2]*SF[7] - P[14][11]*SF[11] + P[14][10]*SPP[7] - (P[14][12]*q0)/2;
+    nextP[14][4] = P[14][4] + P[14][1]*SF[1] + P[14][0]*SF[3] + P[14][2]*SPP[0] - P[14][3]*SPP[2] - P[14][13]*SPP[4];
+    nextP[14][5] = P[14][5] + P[14][0]*SF[2] + P[14][2]*SF[1] + P[14][3]*SF[3] - P[14][1]*SPP[0] + P[14][13]*SPP[3];
+    nextP[14][6] = P[14][6] + P[14][1]*SF[2] + P[14][3]*SF[1] + P[14][0]*SPP[0] - P[14][2]*SPP[1] - P[14][13]*SPP[5];
+    nextP[14][7] = P[14][7] + P[14][4]*dt;
+    nextP[14][8] = P[14][8] + P[14][5]*dt;
+    nextP[14][9] = P[14][9] + P[14][6]*dt;
+    nextP[14][10] = P[14][10];
+    nextP[14][11] = P[14][11];
+    nextP[14][12] = P[14][12];
+    nextP[14][13] = P[14][13];
+    nextP[14][14] = P[14][14];
+    nextP[14][15] = P[14][15];
+    nextP[14][16] = P[14][16];
+    nextP[14][17] = P[14][17];
+    nextP[14][18] = P[14][18];
+    nextP[14][19] = P[14][19];
+    nextP[14][20] = P[14][20];
+    nextP[14][21] = P[14][21];
+    nextP[14][22] = P[14][22];
+    nextP[15][0] = P[15][0] + P[15][1]*SF[7] + P[15][2]*SF[9] + P[15][3]*SF[8] + P[15][10]*SF[11] + P[15][11]*SPP[7] + P[15][12]*SPP[6];
+    nextP[15][1] = P[15][1] + P[15][0]*SF[6] + P[15][2]*SF[5] + P[15][3]*SF[9] + P[15][11]*SPP[6] - P[15][12]*SPP[7] - (P[15][10]*q0)/2;
+    nextP[15][2] = P[15][2] + P[15][0]*SF[4] + P[15][1]*SF[8] + P[15][3]*SF[6] + P[15][12]*SF[11] - P[15][10]*SPP[6] - (P[15][11]*q0)/2;
+    nextP[15][3] = P[15][3] + P[15][0]*SF[5] + P[15][1]*SF[4] + P[15][2]*SF[7] - P[15][11]*SF[11] + P[15][10]*SPP[7] - (P[15][12]*q0)/2;
+    nextP[15][4] = P[15][4] + P[15][1]*SF[1] + P[15][0]*SF[3] + P[15][2]*SPP[0] - P[15][3]*SPP[2] - P[15][13]*SPP[4];
+    nextP[15][5] = P[15][5] + P[15][0]*SF[2] + P[15][2]*SF[1] + P[15][3]*SF[3] - P[15][1]*SPP[0] + P[15][13]*SPP[3];
+    nextP[15][6] = P[15][6] + P[15][1]*SF[2] + P[15][3]*SF[1] + P[15][0]*SPP[0] - P[15][2]*SPP[1] - P[15][13]*SPP[5];
+    nextP[15][7] = P[15][7] + P[15][4]*dt;
+    nextP[15][8] = P[15][8] + P[15][5]*dt;
+    nextP[15][9] = P[15][9] + P[15][6]*dt;
+    nextP[15][10] = P[15][10];
+    nextP[15][11] = P[15][11];
+    nextP[15][12] = P[15][12];
+    nextP[15][13] = P[15][13];
+    nextP[15][14] = P[15][14];
+    nextP[15][15] = P[15][15];
+    nextP[15][16] = P[15][16];
+    nextP[15][17] = P[15][17];
+    nextP[15][18] = P[15][18];
+    nextP[15][19] = P[15][19];
+    nextP[15][20] = P[15][20];
+    nextP[15][21] = P[15][21];
+    nextP[15][22] = P[15][22];
+    nextP[16][0] = P[16][0] + P[16][1]*SF[7] + P[16][2]*SF[9] + P[16][3]*SF[8] + P[16][10]*SF[11] + P[16][11]*SPP[7] + P[16][12]*SPP[6];
+    nextP[16][1] = P[16][1] + P[16][0]*SF[6] + P[16][2]*SF[5] + P[16][3]*SF[9] + P[16][11]*SPP[6] - P[16][12]*SPP[7] - (P[16][10]*q0)/2;
+    nextP[16][2] = P[16][2] + P[16][0]*SF[4] + P[16][1]*SF[8] + P[16][3]*SF[6] + P[16][12]*SF[11] - P[16][10]*SPP[6] - (P[16][11]*q0)/2;
+    nextP[16][3] = P[16][3] + P[16][0]*SF[5] + P[16][1]*SF[4] + P[16][2]*SF[7] - P[16][11]*SF[11] + P[16][10]*SPP[7] - (P[16][12]*q0)/2;
+    nextP[16][4] = P[16][4] + P[16][1]*SF[1] + P[16][0]*SF[3] + P[16][2]*SPP[0] - P[16][3]*SPP[2] - P[16][13]*SPP[4];
+    nextP[16][5] = P[16][5] + P[16][0]*SF[2] + P[16][2]*SF[1] + P[16][3]*SF[3] - P[16][1]*SPP[0] + P[16][13]*SPP[3];
+    nextP[16][6] = P[16][6] + P[16][1]*SF[2] + P[16][3]*SF[1] + P[16][0]*SPP[0] - P[16][2]*SPP[1] - P[16][13]*SPP[5];
+    nextP[16][7] = P[16][7] + P[16][4]*dt;
+    nextP[16][8] = P[16][8] + P[16][5]*dt;
+    nextP[16][9] = P[16][9] + P[16][6]*dt;
+    nextP[16][10] = P[16][10];
+    nextP[16][11] = P[16][11];
+    nextP[16][12] = P[16][12];
+    nextP[16][13] = P[16][13];
+    nextP[16][14] = P[16][14];
+    nextP[16][15] = P[16][15];
+    nextP[16][16] = P[16][16];
+    nextP[16][17] = P[16][17];
+    nextP[16][18] = P[16][18];
+    nextP[16][19] = P[16][19];
+    nextP[16][20] = P[16][20];
+    nextP[16][21] = P[16][21];
+    nextP[16][22] = P[16][22];
+    nextP[17][0] = P[17][0] + P[17][1]*SF[7] + P[17][2]*SF[9] + P[17][3]*SF[8] + P[17][10]*SF[11] + P[17][11]*SPP[7] + P[17][12]*SPP[6];
+    nextP[17][1] = P[17][1] + P[17][0]*SF[6] + P[17][2]*SF[5] + P[17][3]*SF[9] + P[17][11]*SPP[6] - P[17][12]*SPP[7] - (P[17][10]*q0)/2;
+    nextP[17][2] = P[17][2] + P[17][0]*SF[4] + P[17][1]*SF[8] + P[17][3]*SF[6] + P[17][12]*SF[11] - P[17][10]*SPP[6] - (P[17][11]*q0)/2;
+    nextP[17][3] = P[17][3] + P[17][0]*SF[5] + P[17][1]*SF[4] + P[17][2]*SF[7] - P[17][11]*SF[11] + P[17][10]*SPP[7] - (P[17][12]*q0)/2;
+    nextP[17][4] = P[17][4] + P[17][1]*SF[1] + P[17][0]*SF[3] + P[17][2]*SPP[0] - P[17][3]*SPP[2] - P[17][13]*SPP[4];
+    nextP[17][5] = P[17][5] + P[17][0]*SF[2] + P[17][2]*SF[1] + P[17][3]*SF[3] - P[17][1]*SPP[0] + P[17][13]*SPP[3];
+    nextP[17][6] = P[17][6] + P[17][1]*SF[2] + P[17][3]*SF[1] + P[17][0]*SPP[0] - P[17][2]*SPP[1] - P[17][13]*SPP[5];
+    nextP[17][7] = P[17][7] + P[17][4]*dt;
+    nextP[17][8] = P[17][8] + P[17][5]*dt;
+    nextP[17][9] = P[17][9] + P[17][6]*dt;
+    nextP[17][10] = P[17][10];
+    nextP[17][11] = P[17][11];
+    nextP[17][12] = P[17][12];
+    nextP[17][13] = P[17][13];
+    nextP[17][14] = P[17][14];
+    nextP[17][15] = P[17][15];
+    nextP[17][16] = P[17][16];
+    nextP[17][17] = P[17][17];
+    nextP[17][18] = P[17][18];
+    nextP[17][19] = P[17][19];
+    nextP[17][20] = P[17][20];
+    nextP[17][21] = P[17][21];
+    nextP[17][22] = P[17][22];
+    nextP[18][0] = P[18][0] + P[18][1]*SF[7] + P[18][2]*SF[9] + P[18][3]*SF[8] + P[18][10]*SF[11] + P[18][11]*SPP[7] + P[18][12]*SPP[6];
+    nextP[18][1] = P[18][1] + P[18][0]*SF[6] + P[18][2]*SF[5] + P[18][3]*SF[9] + P[18][11]*SPP[6] - P[18][12]*SPP[7] - (P[18][10]*q0)/2;
+    nextP[18][2] = P[18][2] + P[18][0]*SF[4] + P[18][1]*SF[8] + P[18][3]*SF[6] + P[18][12]*SF[11] - P[18][10]*SPP[6] - (P[18][11]*q0)/2;
+    nextP[18][3] = P[18][3] + P[18][0]*SF[5] + P[18][1]*SF[4] + P[18][2]*SF[7] - P[18][11]*SF[11] + P[18][10]*SPP[7] - (P[18][12]*q0)/2;
+    nextP[18][4] = P[18][4] + P[18][1]*SF[1] + P[18][0]*SF[3] + P[18][2]*SPP[0] - P[18][3]*SPP[2] - P[18][13]*SPP[4];
+    nextP[18][5] = P[18][5] + P[18][0]*SF[2] + P[18][2]*SF[1] + P[18][3]*SF[3] - P[18][1]*SPP[0] + P[18][13]*SPP[3];
+    nextP[18][6] = P[18][6] + P[18][1]*SF[2] + P[18][3]*SF[1] + P[18][0]*SPP[0] - P[18][2]*SPP[1] - P[18][13]*SPP[5];
+    nextP[18][7] = P[18][7] + P[18][4]*dt;
+    nextP[18][8] = P[18][8] + P[18][5]*dt;
+    nextP[18][9] = P[18][9] + P[18][6]*dt;
+    nextP[18][10] = P[18][10];
+    nextP[18][11] = P[18][11];
+    nextP[18][12] = P[18][12];
+    nextP[18][13] = P[18][13];
+    nextP[18][14] = P[18][14];
+    nextP[18][15] = P[18][15];
+    nextP[18][16] = P[18][16];
+    nextP[18][17] = P[18][17];
+    nextP[18][18] = P[18][18];
+    nextP[18][19] = P[18][19];
+    nextP[18][20] = P[18][20];
+    nextP[18][21] = P[18][21];
+    nextP[18][22] = P[18][22];
+    nextP[19][0] = P[19][0] + P[19][1]*SF[7] + P[19][2]*SF[9] + P[19][3]*SF[8] + P[19][10]*SF[11] + P[19][11]*SPP[7] + P[19][12]*SPP[6];
+    nextP[19][1] = P[19][1] + P[19][0]*SF[6] + P[19][2]*SF[5] + P[19][3]*SF[9] + P[19][11]*SPP[6] - P[19][12]*SPP[7] - (P[19][10]*q0)/2;
+    nextP[19][2] = P[19][2] + P[19][0]*SF[4] + P[19][1]*SF[8] + P[19][3]*SF[6] + P[19][12]*SF[11] - P[19][10]*SPP[6] - (P[19][11]*q0)/2;
+    nextP[19][3] = P[19][3] + P[19][0]*SF[5] + P[19][1]*SF[4] + P[19][2]*SF[7] - P[19][11]*SF[11] + P[19][10]*SPP[7] - (P[19][12]*q0)/2;
+    nextP[19][4] = P[19][4] + P[19][1]*SF[1] + P[19][0]*SF[3] + P[19][2]*SPP[0] - P[19][3]*SPP[2] - P[19][13]*SPP[4];
+    nextP[19][5] = P[19][5] + P[19][0]*SF[2] + P[19][2]*SF[1] + P[19][3]*SF[3] - P[19][1]*SPP[0] + P[19][13]*SPP[3];
+    nextP[19][6] = P[19][6] + P[19][1]*SF[2] + P[19][3]*SF[1] + P[19][0]*SPP[0] - P[19][2]*SPP[1] - P[19][13]*SPP[5];
+    nextP[19][7] = P[19][7] + P[19][4]*dt;
+    nextP[19][8] = P[19][8] + P[19][5]*dt;
+    nextP[19][9] = P[19][9] + P[19][6]*dt;
+    nextP[19][10] = P[19][10];
+    nextP[19][11] = P[19][11];
+    nextP[19][12] = P[19][12];
+    nextP[19][13] = P[19][13];
+    nextP[19][14] = P[19][14];
+    nextP[19][15] = P[19][15];
+    nextP[19][16] = P[19][16];
+    nextP[19][17] = P[19][17];
+    nextP[19][18] = P[19][18];
+    nextP[19][19] = P[19][19];
+    nextP[19][20] = P[19][20];
+    nextP[19][21] = P[19][21];
+    nextP[19][22] = P[19][22];
+    nextP[20][0] = P[20][0] + P[20][1]*SF[7] + P[20][2]*SF[9] + P[20][3]*SF[8] + P[20][10]*SF[11] + P[20][11]*SPP[7] + P[20][12]*SPP[6];
+    nextP[20][1] = P[20][1] + P[20][0]*SF[6] + P[20][2]*SF[5] + P[20][3]*SF[9] + P[20][11]*SPP[6] - P[20][12]*SPP[7] - (P[20][10]*q0)/2;
+    nextP[20][2] = P[20][2] + P[20][0]*SF[4] + P[20][1]*SF[8] + P[20][3]*SF[6] + P[20][12]*SF[11] - P[20][10]*SPP[6] - (P[20][11]*q0)/2;
+    nextP[20][3] = P[20][3] + P[20][0]*SF[5] + P[20][1]*SF[4] + P[20][2]*SF[7] - P[20][11]*SF[11] + P[20][10]*SPP[7] - (P[20][12]*q0)/2;
+    nextP[20][4] = P[20][4] + P[20][1]*SF[1] + P[20][0]*SF[3] + P[20][2]*SPP[0] - P[20][3]*SPP[2] - P[20][13]*SPP[4];
+    nextP[20][5] = P[20][5] + P[20][0]*SF[2] + P[20][2]*SF[1] + P[20][3]*SF[3] - P[20][1]*SPP[0] + P[20][13]*SPP[3];
+    nextP[20][6] = P[20][6] + P[20][1]*SF[2] + P[20][3]*SF[1] + P[20][0]*SPP[0] - P[20][2]*SPP[1] - P[20][13]*SPP[5];
+    nextP[20][7] = P[20][7] + P[20][4]*dt;
+    nextP[20][8] = P[20][8] + P[20][5]*dt;
+    nextP[20][9] = P[20][9] + P[20][6]*dt;
+    nextP[20][10] = P[20][10];
+    nextP[20][11] = P[20][11];
+    nextP[20][12] = P[20][12];
+    nextP[20][13] = P[20][13];
+    nextP[20][14] = P[20][14];
+    nextP[20][15] = P[20][15];
+    nextP[20][16] = P[20][16];
+    nextP[20][17] = P[20][17];
+    nextP[20][18] = P[20][18];
+    nextP[20][19] = P[20][19];
+    nextP[20][20] = P[20][20];
+    nextP[20][21] = P[20][21];
+    nextP[20][22] = P[20][22];
+    nextP[21][0] = P[21][0] + P[21][1]*SF[7] + P[21][2]*SF[9] + P[21][3]*SF[8] + P[21][10]*SF[11] + P[21][11]*SPP[7] + P[21][12]*SPP[6];
+    nextP[21][1] = P[21][1] + P[21][0]*SF[6] + P[21][2]*SF[5] + P[21][3]*SF[9] + P[21][11]*SPP[6] - P[21][12]*SPP[7] - (P[21][10]*q0)/2;
+    nextP[21][2] = P[21][2] + P[21][0]*SF[4] + P[21][1]*SF[8] + P[21][3]*SF[6] + P[21][12]*SF[11] - P[21][10]*SPP[6] - (P[21][11]*q0)/2;
+    nextP[21][3] = P[21][3] + P[21][0]*SF[5] + P[21][1]*SF[4] + P[21][2]*SF[7] - P[21][11]*SF[11] + P[21][10]*SPP[7] - (P[21][12]*q0)/2;
+    nextP[21][4] = P[21][4] + P[21][1]*SF[1] + P[21][0]*SF[3] + P[21][2]*SPP[0] - P[21][3]*SPP[2] - P[21][13]*SPP[4];
+    nextP[21][5] = P[21][5] + P[21][0]*SF[2] + P[21][2]*SF[1] + P[21][3]*SF[3] - P[21][1]*SPP[0] + P[21][13]*SPP[3];
+    nextP[21][6] = P[21][6] + P[21][1]*SF[2] + P[21][3]*SF[1] + P[21][0]*SPP[0] - P[21][2]*SPP[1] - P[21][13]*SPP[5];
+    nextP[21][7] = P[21][7] + P[21][4]*dt;
+    nextP[21][8] = P[21][8] + P[21][5]*dt;
+    nextP[21][9] = P[21][9] + P[21][6]*dt;
+    nextP[21][10] = P[21][10];
+    nextP[21][11] = P[21][11];
+    nextP[21][12] = P[21][12];
+    nextP[21][13] = P[21][13];
+    nextP[21][14] = P[21][14];
+    nextP[21][15] = P[21][15];
+    nextP[21][16] = P[21][16];
+    nextP[21][17] = P[21][17];
+    nextP[21][18] = P[21][18];
+    nextP[21][19] = P[21][19];
+    nextP[21][20] = P[21][20];
+    nextP[21][21] = P[21][21];
+    nextP[21][22] = P[21][22];
+    nextP[22][0] = P[22][0] + P[22][1]*SF[7] + P[22][2]*SF[9] + P[22][3]*SF[8] + P[22][10]*SF[11] + P[22][11]*SPP[7] + P[22][12]*SPP[6];
+    nextP[22][1] = P[22][1] + P[22][0]*SF[6] + P[22][2]*SF[5] + P[22][3]*SF[9] + P[22][11]*SPP[6] - P[22][12]*SPP[7] - (P[22][10]*q0)/2;
+    nextP[22][2] = P[22][2] + P[22][0]*SF[4] + P[22][1]*SF[8] + P[22][3]*SF[6] + P[22][12]*SF[11] - P[22][10]*SPP[6] - (P[22][11]*q0)/2;
+    nextP[22][3] = P[22][3] + P[22][0]*SF[5] + P[22][1]*SF[4] + P[22][2]*SF[7] - P[22][11]*SF[11] + P[22][10]*SPP[7] - (P[22][12]*q0)/2;
+    nextP[22][4] = P[22][4] + P[22][1]*SF[1] + P[22][0]*SF[3] + P[22][2]*SPP[0] - P[22][3]*SPP[2] - P[22][13]*SPP[4];
+    nextP[22][5] = P[22][5] + P[22][0]*SF[2] + P[22][2]*SF[1] + P[22][3]*SF[3] - P[22][1]*SPP[0] + P[22][13]*SPP[3];
+    nextP[22][6] = P[22][6] + P[22][1]*SF[2] + P[22][3]*SF[1] + P[22][0]*SPP[0] - P[22][2]*SPP[1] - P[22][13]*SPP[5];
+    nextP[22][7] = P[22][7] + P[22][4]*dt;
+    nextP[22][8] = P[22][8] + P[22][5]*dt;
+    nextP[22][9] = P[22][9] + P[22][6]*dt;
+    nextP[22][10] = P[22][10];
+    nextP[22][11] = P[22][11];
+    nextP[22][12] = P[22][12];
+    nextP[22][13] = P[22][13];
+    nextP[22][14] = P[22][14];
+    nextP[22][15] = P[22][15];
+    nextP[22][16] = P[22][16];
+    nextP[22][17] = P[22][17];
+    nextP[22][18] = P[22][18];
+    nextP[22][19] = P[22][19];
+    nextP[22][20] = P[22][20];
+    nextP[22][21] = P[22][21];
+    nextP[22][22] = P[22][22];
+
+    for (unsigned i = 0; i < n_states; i++)
+    {
+        nextP[i][i] = nextP[i][i] + processNoise[i];
+    }
+
+    // If on ground or no magnetometer fitted, inhibit magnetometer bias updates by
+    // setting the coresponding covariance terms to zero.
+    if (onGround || !useCompass)
+    {
+        zeroRows(nextP,16,21);
+        zeroCols(nextP,16,21);
+    }
+
+    // If on ground or not using airspeed sensing, inhibit wind velocity
+    // covariance growth.
+    if (onGround || !useAirspeed)
+    {
+        zeroRows(nextP,14,15);
+        zeroCols(nextP,14,15);
+    }
+
+    // If on ground, inhibit terrain offset updates by
+    // setting the coresponding covariance terms to zero.
+    if (onGround)
+    {
+        zeroRows(nextP,22,22);
+        zeroCols(nextP,22,22);
+    }
+
+    // If the total position variance exceds 1E6 (1000m), then stop covariance
+    // growth by setting the predicted to the previous values
+    // This prevent an ill conditioned matrix from occurring for long periods
+    // without GPS
+    if ((P[7][7] + P[8][8]) > 1E6f)
+    {
+        for (uint8_t i=7; i<=8; i++)
+        {
+            for (unsigned j = 0; j < n_states; j++)
+            {
+                nextP[i][j] = P[i][j];
+                nextP[j][i] = P[j][i];
+            }
+        }
+    }
+
+    if (onGround || staticMode) {
+        // copy the portion of the variances we want to
+        // propagate
+        for (unsigned i = 0; i <= 13; i++) {
+            P[i][i] = nextP[i][i];
+
+            // force symmetry for observable states
+            // force zero for non-observable states
+            for (unsigned i = 1; i < n_states; i++)
+            {
+                for (uint8_t j = 0; j < i; j++)
+                {
+                    if ((i > 13) || (j > 13)) {
+                        P[i][j] = 0.0f;
+                    } else {
+                        P[i][j] = 0.5f * (nextP[i][j] + nextP[j][i]);
+                    }
+                    P[j][i] = P[i][j];
+                }
+            }
+        }
+
+    } else {
+
+        // Copy covariance
+        for (unsigned i = 0; i < n_states; i++) {
+            P[i][i] = nextP[i][i];
+        }
+
+        // force symmetry for observable states
+        for (unsigned i = 1; i < n_states; i++)
+        {
+            for (uint8_t j = 0; j < i; j++)
+            {
+                P[i][j] = 0.5f * (nextP[i][j] + nextP[j][i]);
+                P[j][i] = P[i][j];
+            }
+        }
+
+    }
+
+    ConstrainVariances();
+}
+
+void AttPosEKF::FuseVelposNED()
+{
+
+// declare variables used by fault isolation logic
+    uint32_t gpsRetryTime = 30000; // time in msec before GPS fusion will be retried following innovation consistency failure
+    uint32_t gpsRetryTimeNoTAS = 5000; // retry time if no TAS measurement available
+    uint32_t hgtRetryTime = 5000; // height measurement retry time
+    uint32_t horizRetryTime;
+
+// declare variables used to check measurement errors
+    float velInnov[3] = {0.0f,0.0f,0.0f};
+    float posInnov[2] = {0.0f,0.0f};
+    float hgtInnov = 0.0f;
+
+// declare variables used to control access to arrays
+    bool fuseData[6] = {false,false,false,false,false,false};
+    uint8_t stateIndex;
+    uint8_t obsIndex;
+    uint8_t indexLimit;
+
+// declare variables used by state and covariance update calculations
+    float velErr;
+    float posErr;
+    float R_OBS[6];
+    float observation[6];
+    float SK;
+    float quatMag;
+
+// Perform sequential fusion of GPS measurements. This assumes that the
+// errors in the different velocity and position components are
+// uncorrelated which is not true, however in the absence of covariance
+// data from the GPS receiver it is the only assumption we can make
+// so we might as well take advantage of the computational efficiencies
+// associated with sequential fusion
+    if (fuseVelData || fusePosData || fuseHgtData)
+    {
+        // set the GPS data timeout depending on whether airspeed data is present
+        if (useAirspeed) horizRetryTime = gpsRetryTime;
+        else horizRetryTime = gpsRetryTimeNoTAS;
+
+        // Form the observation vector
+        for (uint8_t i=0; i<=2; i++) observation[i] = velNED[i];
+        for (uint8_t i=3; i<=4; i++) observation[i] = posNE[i-3];
+        observation[5] = -(hgtMea);
+
+        // Estimate the GPS Velocity, GPS horiz position and height measurement variances.
+        velErr = 0.2f*accNavMag; // additional error in GPS velocities caused by manoeuvring
+        posErr = 0.2f*accNavMag; // additional error in GPS position caused by manoeuvring
+        R_OBS[0] = sq(vneSigma) + sq(velErr);
+        R_OBS[1] = R_OBS[0];
+        R_OBS[2] = sq(vdSigma) + sq(velErr);
+        R_OBS[3] = sq(posNeSigma) + sq(posErr);
+        R_OBS[4] = R_OBS[3];
+        R_OBS[5] = sq(posDSigma) + sq(posErr);
+
+        // Set innovation variances to zero default
+        for (uint8_t i = 0; i<=5; i++)
+        {
+            varInnovVelPos[i] = 0.0f;
+        }
+        // calculate innovations and check GPS data validity using an innovation consistency check
+        if (fuseVelData)
+        {
+            // test velocity measurements
+            uint8_t imax = 2;
+            if (fusionModeGPS == 1) imax = 1;
+            for (uint8_t i = 0; i<=imax; i++)
+            {
+                velInnov[i] = statesAtVelTime[i+4] - velNED[i];
+                stateIndex = 4 + i;
+                varInnovVelPos[i] = P[stateIndex][stateIndex] + R_OBS[i];
+            }
+            // apply a 5-sigma threshold
+            current_ekf_state.velHealth = (sq(velInnov[0]) + sq(velInnov[1]) + sq(velInnov[2])) < 25.0f * (varInnovVelPos[0] + varInnovVelPos[1] + varInnovVelPos[2]);
+            current_ekf_state.velTimeout = (millis() - current_ekf_state.velFailTime) > horizRetryTime;
+            if (current_ekf_state.velHealth || current_ekf_state.velTimeout)
+            {
+                current_ekf_state.velHealth = true;
+                current_ekf_state.velFailTime = millis();
+            }
+            else
+            {
+                current_ekf_state.velHealth = false;
+            }
+        }
+        if (fusePosData)
+        {
+            // test horizontal position measurements
+            posInnov[0] = statesAtPosTime[7] - posNE[0];
+            posInnov[1] = statesAtPosTime[8] - posNE[1];
+            varInnovVelPos[3] = P[7][7] + R_OBS[3];
+            varInnovVelPos[4] = P[8][8] + R_OBS[4];
+            // apply a 10-sigma threshold
+            current_ekf_state.posHealth = (sq(posInnov[0]) + sq(posInnov[1])) < 100.0f*(varInnovVelPos[3] + varInnovVelPos[4]);
+            current_ekf_state.posTimeout = (millis() - current_ekf_state.posFailTime) > horizRetryTime;
+            if (current_ekf_state.posHealth || current_ekf_state.posTimeout)
+            {
+                current_ekf_state.posHealth = true;
+                current_ekf_state.posFailTime = millis();
+            }
+            else
+            {
+                current_ekf_state.posHealth = false;
+            }
+        }
+        // test height measurements
+        if (fuseHgtData)
+        {
+            hgtInnov = statesAtHgtTime[9] + hgtMea;
+            varInnovVelPos[5] = P[9][9] + R_OBS[5];
+            // apply a 10-sigma threshold
+            current_ekf_state.hgtHealth = sq(hgtInnov) < 100.0f*varInnovVelPos[5];
+            current_ekf_state.hgtTimeout = (millis() - current_ekf_state.hgtFailTime) > hgtRetryTime;
+            if (current_ekf_state.hgtHealth || current_ekf_state.hgtTimeout)
+            {
+                current_ekf_state.hgtHealth = true;
+                current_ekf_state.hgtFailTime = millis();
+            }
+            else
+            {
+                current_ekf_state.hgtHealth = false;
+            }
+        }
+        // Set range for sequential fusion of velocity and position measurements depending
+        // on which data is available and its health
+        if (fuseVelData && fusionModeGPS == 0 && current_ekf_state.velHealth)
+        {
+            fuseData[0] = true;
+            fuseData[1] = true;
+            fuseData[2] = true;
+        }
+        if (fuseVelData && fusionModeGPS == 1 && current_ekf_state.velHealth)
+        {
+            fuseData[0] = true;
+            fuseData[1] = true;
+        }
+        if (fusePosData && fusionModeGPS <= 2 && current_ekf_state.posHealth)
+        {
+            fuseData[3] = true;
+            fuseData[4] = true;
+        }
+        if (fuseHgtData && current_ekf_state.hgtHealth)
+        {
+            fuseData[5] = true;
+        }
+        // Limit range of states modified when on ground
+        if(!onGround)
+        {
+            indexLimit = 22;
+        }
+        else
+        {
+            indexLimit = 13;
+        }
+        // Fuse measurements sequentially
+        for (obsIndex=0; obsIndex<=5; obsIndex++)
+        {
+            if (fuseData[obsIndex])
+            {
+                stateIndex = 4 + obsIndex;
+                // Calculate the measurement innovation, using states from a
+                // different time coordinate if fusing height data
+                if (obsIndex >= 0 && obsIndex <= 2)
+                {
+                    innovVelPos[obsIndex] = statesAtVelTime[stateIndex] - observation[obsIndex];
+                }
+                else if (obsIndex == 3 || obsIndex == 4)
+                {
+                    innovVelPos[obsIndex] = statesAtPosTime[stateIndex] - observation[obsIndex];
+                }
+                else if (obsIndex == 5)
+                {
+                    innovVelPos[obsIndex] = statesAtHgtTime[stateIndex] - observation[obsIndex];
+                }
+                // Calculate the Kalman Gain
+                // Calculate innovation variances - also used for data logging
+                varInnovVelPos[obsIndex] = P[stateIndex][stateIndex] + R_OBS[obsIndex];
+                SK = 1.0/varInnovVelPos[obsIndex];
+                for (uint8_t i= 0; i<=indexLimit; i++)
+                {
+                    Kfusion[i] = P[i][stateIndex]*SK;
+                }
+
+                // Don't update Z accel bias state unless using a height observation (GPS velocities can be biased)
+                if (obsIndex != 5) {
+                    Kfusion[13] = 0;
+                }
+
+                // Calculate state corrections and re-normalise the quaternions
+                for (uint8_t i = 0; i<=indexLimit; i++)
+                {
+                    states[i] = states[i] - Kfusion[i] * innovVelPos[obsIndex];
+                }
+                quatMag = sqrt(states[0]*states[0] + states[1]*states[1] + states[2]*states[2] + states[3]*states[3]);
+                if (quatMag > 1e-12f) // divide by  0 protection
+                {
+                    for (uint8_t i = 0; i<=3; i++)
+                    {
+                        states[i] = states[i] / quatMag;
+                    }
+                }
+                // Update the covariance - take advantage of direct observation of a
+                // single state at index = stateIndex to reduce computations
+                // Optimised implementation of standard equation P = (I - K*H)*P;
+                for (uint8_t i= 0; i<=indexLimit; i++)
+                {
+                    for (uint8_t j= 0; j<=indexLimit; j++)
+                    {
+                        KHP[i][j] = Kfusion[i] * P[stateIndex][j];
+                    }
+                }
+                for (uint8_t i= 0; i<=indexLimit; i++)
+                {
+                    for (uint8_t j= 0; j<=indexLimit; j++)
+                    {
+                        P[i][j] = P[i][j] - KHP[i][j];
+                    }
+                }
+            }
+        }
+    }
+
+    ForceSymmetry();
+    ConstrainVariances();
+
+}
+
+void AttPosEKF::FuseMagnetometer()
+{
+
+    float &q0 = magstate.q0;
+    float &q1 = magstate.q1;
+    float &q2 = magstate.q2;
+    float &q3 = magstate.q3;
+    float &magN = magstate.magN;
+    float &magE = magstate.magE;
+    float &magD = magstate.magD;
+    float &magXbias = magstate.magXbias;
+    float &magYbias = magstate.magYbias;
+    float &magZbias = magstate.magZbias;
+    unsigned &obsIndex = magstate.obsIndex;
+    Mat3f &DCM = magstate.DCM;
+    float *MagPred = &magstate.MagPred[0];
+    float &R_MAG = magstate.R_MAG;
+    float *SH_MAG = &magstate.SH_MAG[0];
+
+    float SK_MX[6];
+    float SK_MY[5];
+    float SK_MZ[6];
+    float H_MAG[n_states];
+    for (uint8_t i = 0; i < n_states; i++) {
+        H_MAG[i] = 0.0f;
+    }
+    uint8_t indexLimit;
+
+// Perform sequential fusion of Magnetometer measurements.
+// This assumes that the errors in the different components are
+// uncorrelated which is not true, however in the absence of covariance
+// data fit is the only assumption we can make
+// so we might as well take advantage of the computational efficiencies
+// associated with sequential fusion
+    if (useCompass && (fuseMagData || obsIndex == 1 || obsIndex == 2))
+    {
+        // Limit range of states modified when on ground
+        if(!onGround)
+        {
+            indexLimit = 22;
+        }
+        else
+        {
+            indexLimit = 13;
+        }
+
+        // Sequential fusion of XYZ components to spread processing load across
+        // three prediction time steps.
+
+        // Calculate observation jacobians and Kalman gains
+        if (fuseMagData)
+        {
+            // Copy required states to local variable names
+            q0       = statesAtMagMeasTime[0];
+            q1       = statesAtMagMeasTime[1];
+            q2       = statesAtMagMeasTime[2];
+            q3       = statesAtMagMeasTime[3];
+            magN     = statesAtMagMeasTime[16];
+            magE     = statesAtMagMeasTime[17];
+            magD     = statesAtMagMeasTime[18];
+            magXbias = statesAtMagMeasTime[19];
+            magYbias = statesAtMagMeasTime[20];
+            magZbias = statesAtMagMeasTime[21];
+
+            // rotate predicted earth components into body axes and calculate
+            // predicted measurments
+            DCM.x.x = q0*q0 + q1*q1 - q2*q2 - q3*q3;
+            DCM.x.y = 2*(q1*q2 + q0*q3);
+            DCM.x.z = 2*(q1*q3-q0*q2);
+            DCM.y.x = 2*(q1*q2 - q0*q3);
+            DCM.y.y = q0*q0 - q1*q1 + q2*q2 - q3*q3;
+            DCM.y.z = 2*(q2*q3 + q0*q1);
+            DCM.z.x = 2*(q1*q3 + q0*q2);
+            DCM.z.y = 2*(q2*q3 - q0*q1);
+            DCM.z.z = q0*q0 - q1*q1 - q2*q2 + q3*q3;
+            MagPred[0] = DCM.x.x*magN + DCM.x.y*magE  + DCM.x.z*magD + magXbias;
+            MagPred[1] = DCM.y.x*magN + DCM.y.y*magE  + DCM.y.z*magD + magYbias;
+            MagPred[2] = DCM.z.x*magN + DCM.z.y*magE  + DCM.z.z*magD + magZbias;
+
+            // scale magnetometer observation error with total angular rate
+            R_MAG = sq(magMeasurementSigma) + sq(0.05f*dAngIMU.length()/dtIMU);
+
+            // Calculate observation jacobians
+            SH_MAG[0] = 2*magD*q3 + 2*magE*q2 + 2*magN*q1;
+            SH_MAG[1] = 2*magD*q0 - 2*magE*q1 + 2*magN*q2;
+            SH_MAG[2] = 2*magD*q1 + 2*magE*q0 - 2*magN*q3;
+            SH_MAG[3] = sq(q3);
+            SH_MAG[4] = sq(q2);
+            SH_MAG[5] = sq(q1);
+            SH_MAG[6] = sq(q0);
+            SH_MAG[7] = 2*magN*q0;
+            SH_MAG[8] = 2*magE*q3;
+
+            for (uint8_t i = 0; i < n_states; i++) H_MAG[i] = 0;
+            H_MAG[0] = SH_MAG[7] + SH_MAG[8] - 2*magD*q2;
+            H_MAG[1] = SH_MAG[0];
+            H_MAG[2] = 2*magE*q1 - 2*magD*q0 - 2*magN*q2;
+            H_MAG[3] = SH_MAG[2];
+            H_MAG[16] = SH_MAG[5] - SH_MAG[4] - SH_MAG[3] + SH_MAG[6];
+            H_MAG[17] = 2*q0*q3 + 2*q1*q2;
+            H_MAG[18] = 2*q1*q3 - 2*q0*q2;
+            H_MAG[19] = 1.0f;
+
+            // Calculate Kalman gain
+            SK_MX[0] = 1/(P[19][19] + R_MAG + P[1][19]*SH_MAG[0] + P[3][19]*SH_MAG[2] - P[16][19]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) - (2*magD*q0 - 2*magE*q1 + 2*magN*q2)*(P[19][2] + P[1][2]*SH_MAG[0] + P[3][2]*SH_MAG[2] - P[16][2]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[17][2]*(2*q0*q3 + 2*q1*q2) - P[18][2]*(2*q0*q2 - 2*q1*q3) - P[2][2]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][2]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + (SH_MAG[7] + SH_MAG[8] - 2*magD*q2)*(P[19][0] + P[1][0]*SH_MAG[0] + P[3][0]*SH_MAG[2] - P[16][0]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[17][0]*(2*q0*q3 + 2*q1*q2) - P[18][0]*(2*q0*q2 - 2*q1*q3) - P[2][0]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][0]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + SH_MAG[0]*(P[19][1] + P[1][1]*SH_MAG[0] + P[3][1]*SH_MAG[2] - P[16][1]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[17][1]*(2*q0*q3 + 2*q1*q2) - P[18][1]*(2*q0*q2 - 2*q1*q3) - P[2][1]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][1]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + SH_MAG[2]*(P[19][3] + P[1][3]*SH_MAG[0] + P[3][3]*SH_MAG[2] - P[16][3]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[17][3]*(2*q0*q3 + 2*q1*q2) - P[18][3]*(2*q0*q2 - 2*q1*q3) - P[2][3]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][3]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - (SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6])*(P[19][16] + P[1][16]*SH_MAG[0] + P[3][16]*SH_MAG[2] - P[16][16]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[17][16]*(2*q0*q3 + 2*q1*q2) - P[18][16]*(2*q0*q2 - 2*q1*q3) - P[2][16]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][16]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + P[17][19]*(2*q0*q3 + 2*q1*q2) - P[18][19]*(2*q0*q2 - 2*q1*q3) - P[2][19]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + (2*q0*q3 + 2*q1*q2)*(P[19][17] + P[1][17]*SH_MAG[0] + P[3][17]*SH_MAG[2] - P[16][17]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[17][17]*(2*q0*q3 + 2*q1*q2) - P[18][17]*(2*q0*q2 - 2*q1*q3) - P[2][17]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][17]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - (2*q0*q2 - 2*q1*q3)*(P[19][18] + P[1][18]*SH_MAG[0] + P[3][18]*SH_MAG[2] - P[16][18]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[17][18]*(2*q0*q3 + 2*q1*q2) - P[18][18]*(2*q0*q2 - 2*q1*q3) - P[2][18]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][18]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + P[0][19]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2));
+            SK_MX[1] = SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6];
+            SK_MX[2] = 2*magD*q0 - 2*magE*q1 + 2*magN*q2;
+            SK_MX[3] = SH_MAG[7] + SH_MAG[8] - 2*magD*q2;
+            SK_MX[4] = 2*q0*q2 - 2*q1*q3;
+            SK_MX[5] = 2*q0*q3 + 2*q1*q2;
+            Kfusion[0] = SK_MX[0]*(P[0][19] + P[0][1]*SH_MAG[0] + P[0][3]*SH_MAG[2] + P[0][0]*SK_MX[3] - P[0][2]*SK_MX[2] - P[0][16]*SK_MX[1] + P[0][17]*SK_MX[5] - P[0][18]*SK_MX[4]);
+            Kfusion[1] = SK_MX[0]*(P[1][19] + P[1][1]*SH_MAG[0] + P[1][3]*SH_MAG[2] + P[1][0]*SK_MX[3] - P[1][2]*SK_MX[2] - P[1][16]*SK_MX[1] + P[1][17]*SK_MX[5] - P[1][18]*SK_MX[4]);
+            Kfusion[2] = SK_MX[0]*(P[2][19] + P[2][1]*SH_MAG[0] + P[2][3]*SH_MAG[2] + P[2][0]*SK_MX[3] - P[2][2]*SK_MX[2] - P[2][16]*SK_MX[1] + P[2][17]*SK_MX[5] - P[2][18]*SK_MX[4]);
+            Kfusion[3] = SK_MX[0]*(P[3][19] + P[3][1]*SH_MAG[0] + P[3][3]*SH_MAG[2] + P[3][0]*SK_MX[3] - P[3][2]*SK_MX[2] - P[3][16]*SK_MX[1] + P[3][17]*SK_MX[5] - P[3][18]*SK_MX[4]);
+            Kfusion[4] = SK_MX[0]*(P[4][19] + P[4][1]*SH_MAG[0] + P[4][3]*SH_MAG[2] + P[4][0]*SK_MX[3] - P[4][2]*SK_MX[2] - P[4][16]*SK_MX[1] + P[4][17]*SK_MX[5] - P[4][18]*SK_MX[4]);
+            Kfusion[5] = SK_MX[0]*(P[5][19] + P[5][1]*SH_MAG[0] + P[5][3]*SH_MAG[2] + P[5][0]*SK_MX[3] - P[5][2]*SK_MX[2] - P[5][16]*SK_MX[1] + P[5][17]*SK_MX[5] - P[5][18]*SK_MX[4]);
+            Kfusion[6] = SK_MX[0]*(P[6][19] + P[6][1]*SH_MAG[0] + P[6][3]*SH_MAG[2] + P[6][0]*SK_MX[3] - P[6][2]*SK_MX[2] - P[6][16]*SK_MX[1] + P[6][17]*SK_MX[5] - P[6][18]*SK_MX[4]);
+            Kfusion[7] = SK_MX[0]*(P[7][19] + P[7][1]*SH_MAG[0] + P[7][3]*SH_MAG[2] + P[7][0]*SK_MX[3] - P[7][2]*SK_MX[2] - P[7][16]*SK_MX[1] + P[7][17]*SK_MX[5] - P[7][18]*SK_MX[4]);
+            Kfusion[8] = SK_MX[0]*(P[8][19] + P[8][1]*SH_MAG[0] + P[8][3]*SH_MAG[2] + P[8][0]*SK_MX[3] - P[8][2]*SK_MX[2] - P[8][16]*SK_MX[1] + P[8][17]*SK_MX[5] - P[8][18]*SK_MX[4]);
+            Kfusion[9] = SK_MX[0]*(P[9][19] + P[9][1]*SH_MAG[0] + P[9][3]*SH_MAG[2] + P[9][0]*SK_MX[3] - P[9][2]*SK_MX[2] - P[9][16]*SK_MX[1] + P[9][17]*SK_MX[5] - P[9][18]*SK_MX[4]);
+            Kfusion[10] = SK_MX[0]*(P[10][19] + P[10][1]*SH_MAG[0] + P[10][3]*SH_MAG[2] + P[10][0]*SK_MX[3] - P[10][2]*SK_MX[2] - P[10][16]*SK_MX[1] + P[10][17]*SK_MX[5] - P[10][18]*SK_MX[4]);
+            Kfusion[11] = SK_MX[0]*(P[11][19] + P[11][1]*SH_MAG[0] + P[11][3]*SH_MAG[2] + P[11][0]*SK_MX[3] - P[11][2]*SK_MX[2] - P[11][16]*SK_MX[1] + P[11][17]*SK_MX[5] - P[11][18]*SK_MX[4]);
+            Kfusion[12] = SK_MX[0]*(P[12][19] + P[12][1]*SH_MAG[0] + P[12][3]*SH_MAG[2] + P[12][0]*SK_MX[3] - P[12][2]*SK_MX[2] - P[12][16]*SK_MX[1] + P[12][17]*SK_MX[5] - P[12][18]*SK_MX[4]);
+            // Only height measurements are allowed to modify the Z delta velocity bias state. This improves the stability of the estimate
+            Kfusion[13] = 0.0f;//SK_MX[0]*(P[13][19] + P[13][1]*SH_MAG[0] + P[13][3]*SH_MAG[2] + P[13][0]*SK_MX[3] - P[13][2]*SK_MX[2] - P[13][16]*SK_MX[1] + P[13][17]*SK_MX[5] - P[13][18]*SK_MX[4]);
+            Kfusion[14] = SK_MX[0]*(P[14][19] + P[14][1]*SH_MAG[0] + P[14][3]*SH_MAG[2] + P[14][0]*SK_MX[3] - P[14][2]*SK_MX[2] - P[14][16]*SK_MX[1] + P[14][17]*SK_MX[5] - P[14][18]*SK_MX[4]);
+            Kfusion[15] = SK_MX[0]*(P[15][19] + P[15][1]*SH_MAG[0] + P[15][3]*SH_MAG[2] + P[15][0]*SK_MX[3] - P[15][2]*SK_MX[2] - P[15][16]*SK_MX[1] + P[15][17]*SK_MX[5] - P[15][18]*SK_MX[4]);
+            Kfusion[16] = SK_MX[0]*(P[16][19] + P[16][1]*SH_MAG[0] + P[16][3]*SH_MAG[2] + P[16][0]*SK_MX[3] - P[16][2]*SK_MX[2] - P[16][16]*SK_MX[1] + P[16][17]*SK_MX[5] - P[16][18]*SK_MX[4]);
+            Kfusion[17] = SK_MX[0]*(P[17][19] + P[17][1]*SH_MAG[0] + P[17][3]*SH_MAG[2] + P[17][0]*SK_MX[3] - P[17][2]*SK_MX[2] - P[17][16]*SK_MX[1] + P[17][17]*SK_MX[5] - P[17][18]*SK_MX[4]);
+            Kfusion[18] = SK_MX[0]*(P[18][19] + P[18][1]*SH_MAG[0] + P[18][3]*SH_MAG[2] + P[18][0]*SK_MX[3] - P[18][2]*SK_MX[2] - P[18][16]*SK_MX[1] + P[18][17]*SK_MX[5] - P[18][18]*SK_MX[4]);
+            Kfusion[19] = SK_MX[0]*(P[19][19] + P[19][1]*SH_MAG[0] + P[19][3]*SH_MAG[2] + P[19][0]*SK_MX[3] - P[19][2]*SK_MX[2] - P[19][16]*SK_MX[1] + P[19][17]*SK_MX[5] - P[19][18]*SK_MX[4]);
+            Kfusion[20] = SK_MX[0]*(P[20][19] + P[20][1]*SH_MAG[0] + P[20][3]*SH_MAG[2] + P[20][0]*SK_MX[3] - P[20][2]*SK_MX[2] - P[20][16]*SK_MX[1] + P[20][17]*SK_MX[5] - P[20][18]*SK_MX[4]);
+            Kfusion[21] = SK_MX[0]*(P[21][19] + P[21][1]*SH_MAG[0] + P[21][3]*SH_MAG[2] + P[21][0]*SK_MX[3] - P[21][2]*SK_MX[2] - P[21][16]*SK_MX[1] + P[21][17]*SK_MX[5] - P[21][18]*SK_MX[4]);
+            Kfusion[22] = SK_MX[0]*(P[22][19] + P[22][1]*SH_MAG[0] + P[22][3]*SH_MAG[2] + P[22][0]*SK_MX[3] - P[22][2]*SK_MX[2] - P[22][16]*SK_MX[1] + P[22][17]*SK_MX[5] - P[22][18]*SK_MX[4]);
+            varInnovMag[0] = 1.0f/SK_MX[0];
+            innovMag[0] = MagPred[0] - magData.x;
+
+            // reset the observation index to 0 (we start by fusing the X
+            // measurement)
+            obsIndex = 0;
+            fuseMagData = false;
+        }
+        else if (obsIndex == 1) // we are now fusing the Y measurement
+        {
+            // Calculate observation jacobians
+            for (unsigned int i = 0; i < n_states; i++) H_MAG[i] = 0;
+            H_MAG[0] = SH_MAG[2];
+            H_MAG[1] = SH_MAG[1];
+            H_MAG[2] = SH_MAG[0];
+            H_MAG[3] = 2*magD*q2 - SH_MAG[8] - SH_MAG[7];
+            H_MAG[16] = 2*q1*q2 - 2*q0*q3;
+            H_MAG[17] = SH_MAG[4] - SH_MAG[3] - SH_MAG[5] + SH_MAG[6];
+            H_MAG[18] = 2*q0*q1 + 2*q2*q3;
+            H_MAG[20] = 1;
+
+            // Calculate Kalman gain
+            SK_MY[0] = 1/(P[20][20] + R_MAG + P[0][20]*SH_MAG[2] + P[1][20]*SH_MAG[1] + P[2][20]*SH_MAG[0] - P[17][20]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - (2*q0*q3 - 2*q1*q2)*(P[20][16] + P[0][16]*SH_MAG[2] + P[1][16]*SH_MAG[1] + P[2][16]*SH_MAG[0] - P[17][16]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[16][16]*(2*q0*q3 - 2*q1*q2) + P[18][16]*(2*q0*q1 + 2*q2*q3) - P[3][16]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + (2*q0*q1 + 2*q2*q3)*(P[20][18] + P[0][18]*SH_MAG[2] + P[1][18]*SH_MAG[1] + P[2][18]*SH_MAG[0] - P[17][18]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[16][18]*(2*q0*q3 - 2*q1*q2) + P[18][18]*(2*q0*q1 + 2*q2*q3) - P[3][18]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - (SH_MAG[7] + SH_MAG[8] - 2*magD*q2)*(P[20][3] + P[0][3]*SH_MAG[2] + P[1][3]*SH_MAG[1] + P[2][3]*SH_MAG[0] - P[17][3]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[16][3]*(2*q0*q3 - 2*q1*q2) + P[18][3]*(2*q0*q1 + 2*q2*q3) - P[3][3]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - P[16][20]*(2*q0*q3 - 2*q1*q2) + P[18][20]*(2*q0*q1 + 2*q2*q3) + SH_MAG[2]*(P[20][0] + P[0][0]*SH_MAG[2] + P[1][0]*SH_MAG[1] + P[2][0]*SH_MAG[0] - P[17][0]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[16][0]*(2*q0*q3 - 2*q1*q2) + P[18][0]*(2*q0*q1 + 2*q2*q3) - P[3][0]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + SH_MAG[1]*(P[20][1] + P[0][1]*SH_MAG[2] + P[1][1]*SH_MAG[1] + P[2][1]*SH_MAG[0] - P[17][1]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[16][1]*(2*q0*q3 - 2*q1*q2) + P[18][1]*(2*q0*q1 + 2*q2*q3) - P[3][1]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + SH_MAG[0]*(P[20][2] + P[0][2]*SH_MAG[2] + P[1][2]*SH_MAG[1] + P[2][2]*SH_MAG[0] - P[17][2]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[16][2]*(2*q0*q3 - 2*q1*q2) + P[18][2]*(2*q0*q1 + 2*q2*q3) - P[3][2]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - (SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6])*(P[20][17] + P[0][17]*SH_MAG[2] + P[1][17]*SH_MAG[1] + P[2][17]*SH_MAG[0] - P[17][17]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[16][17]*(2*q0*q3 - 2*q1*q2) + P[18][17]*(2*q0*q1 + 2*q2*q3) - P[3][17]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - P[3][20]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2));
+            SK_MY[1] = SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6];
+            SK_MY[2] = SH_MAG[7] + SH_MAG[8] - 2*magD*q2;
+            SK_MY[3] = 2*q0*q3 - 2*q1*q2;
+            SK_MY[4] = 2*q0*q1 + 2*q2*q3;
+            Kfusion[0] = SK_MY[0]*(P[0][20] + P[0][0]*SH_MAG[2] + P[0][1]*SH_MAG[1] + P[0][2]*SH_MAG[0] - P[0][3]*SK_MY[2] - P[0][17]*SK_MY[1] - P[0][16]*SK_MY[3] + P[0][18]*SK_MY[4]);
+            Kfusion[1] = SK_MY[0]*(P[1][20] + P[1][0]*SH_MAG[2] + P[1][1]*SH_MAG[1] + P[1][2]*SH_MAG[0] - P[1][3]*SK_MY[2] - P[1][17]*SK_MY[1] - P[1][16]*SK_MY[3] + P[1][18]*SK_MY[4]);
+            Kfusion[2] = SK_MY[0]*(P[2][20] + P[2][0]*SH_MAG[2] + P[2][1]*SH_MAG[1] + P[2][2]*SH_MAG[0] - P[2][3]*SK_MY[2] - P[2][17]*SK_MY[1] - P[2][16]*SK_MY[3] + P[2][18]*SK_MY[4]);
+            Kfusion[3] = SK_MY[0]*(P[3][20] + P[3][0]*SH_MAG[2] + P[3][1]*SH_MAG[1] + P[3][2]*SH_MAG[0] - P[3][3]*SK_MY[2] - P[3][17]*SK_MY[1] - P[3][16]*SK_MY[3] + P[3][18]*SK_MY[4]);
+            Kfusion[4] = SK_MY[0]*(P[4][20] + P[4][0]*SH_MAG[2] + P[4][1]*SH_MAG[1] + P[4][2]*SH_MAG[0] - P[4][3]*SK_MY[2] - P[4][17]*SK_MY[1] - P[4][16]*SK_MY[3] + P[4][18]*SK_MY[4]);
+            Kfusion[5] = SK_MY[0]*(P[5][20] + P[5][0]*SH_MAG[2] + P[5][1]*SH_MAG[1] + P[5][2]*SH_MAG[0] - P[5][3]*SK_MY[2] - P[5][17]*SK_MY[1] - P[5][16]*SK_MY[3] + P[5][18]*SK_MY[4]);
+            Kfusion[6] = SK_MY[0]*(P[6][20] + P[6][0]*SH_MAG[2] + P[6][1]*SH_MAG[1] + P[6][2]*SH_MAG[0] - P[6][3]*SK_MY[2] - P[6][17]*SK_MY[1] - P[6][16]*SK_MY[3] + P[6][18]*SK_MY[4]);
+            Kfusion[7] = SK_MY[0]*(P[7][20] + P[7][0]*SH_MAG[2] + P[7][1]*SH_MAG[1] + P[7][2]*SH_MAG[0] - P[7][3]*SK_MY[2] - P[7][17]*SK_MY[1] - P[7][16]*SK_MY[3] + P[7][18]*SK_MY[4]);
+            Kfusion[8] = SK_MY[0]*(P[8][20] + P[8][0]*SH_MAG[2] + P[8][1]*SH_MAG[1] + P[8][2]*SH_MAG[0] - P[8][3]*SK_MY[2] - P[8][17]*SK_MY[1] - P[8][16]*SK_MY[3] + P[8][18]*SK_MY[4]);
+            Kfusion[9] = SK_MY[0]*(P[9][20] + P[9][0]*SH_MAG[2] + P[9][1]*SH_MAG[1] + P[9][2]*SH_MAG[0] - P[9][3]*SK_MY[2] - P[9][17]*SK_MY[1] - P[9][16]*SK_MY[3] + P[9][18]*SK_MY[4]);
+            Kfusion[10] = SK_MY[0]*(P[10][20] + P[10][0]*SH_MAG[2] + P[10][1]*SH_MAG[1] + P[10][2]*SH_MAG[0] - P[10][3]*SK_MY[2] - P[10][17]*SK_MY[1] - P[10][16]*SK_MY[3] + P[10][18]*SK_MY[4]);
+            Kfusion[11] = SK_MY[0]*(P[11][20] + P[11][0]*SH_MAG[2] + P[11][1]*SH_MAG[1] + P[11][2]*SH_MAG[0] - P[11][3]*SK_MY[2] - P[11][17]*SK_MY[1] - P[11][16]*SK_MY[3] + P[11][18]*SK_MY[4]);
+            Kfusion[12] = SK_MY[0]*(P[12][20] + P[12][0]*SH_MAG[2] + P[12][1]*SH_MAG[1] + P[12][2]*SH_MAG[0] - P[12][3]*SK_MY[2] - P[12][17]*SK_MY[1] - P[12][16]*SK_MY[3] + P[12][18]*SK_MY[4]);
+            // Only height measurements are allowed to modify the Z delta velocity bias state. This improves the stability of the estimate
+            Kfusion[13] = 0.0f;//SK_MY[0]*(P[13][20] + P[13][0]*SH_MAG[2] + P[13][1]*SH_MAG[1] + P[13][2]*SH_MAG[0] - P[13][3]*SK_MY[2] - P[13][17]*SK_MY[1] - P[13][16]*SK_MY[3] + P[13][18]*SK_MY[4]);
+            Kfusion[14] = SK_MY[0]*(P[14][20] + P[14][0]*SH_MAG[2] + P[14][1]*SH_MAG[1] + P[14][2]*SH_MAG[0] - P[14][3]*SK_MY[2] - P[14][17]*SK_MY[1] - P[14][16]*SK_MY[3] + P[14][18]*SK_MY[4]);
+            Kfusion[15] = SK_MY[0]*(P[15][20] + P[15][0]*SH_MAG[2] + P[15][1]*SH_MAG[1] + P[15][2]*SH_MAG[0] - P[15][3]*SK_MY[2] - P[15][17]*SK_MY[1] - P[15][16]*SK_MY[3] + P[15][18]*SK_MY[4]);
+            Kfusion[16] = SK_MY[0]*(P[16][20] + P[16][0]*SH_MAG[2] + P[16][1]*SH_MAG[1] + P[16][2]*SH_MAG[0] - P[16][3]*SK_MY[2] - P[16][17]*SK_MY[1] - P[16][16]*SK_MY[3] + P[16][18]*SK_MY[4]);
+            Kfusion[17] = SK_MY[0]*(P[17][20] + P[17][0]*SH_MAG[2] + P[17][1]*SH_MAG[1] + P[17][2]*SH_MAG[0] - P[17][3]*SK_MY[2] - P[17][17]*SK_MY[1] - P[17][16]*SK_MY[3] + P[17][18]*SK_MY[4]);
+            Kfusion[18] = SK_MY[0]*(P[18][20] + P[18][0]*SH_MAG[2] + P[18][1]*SH_MAG[1] + P[18][2]*SH_MAG[0] - P[18][3]*SK_MY[2] - P[18][17]*SK_MY[1] - P[18][16]*SK_MY[3] + P[18][18]*SK_MY[4]);
+            Kfusion[19] = SK_MY[0]*(P[19][20] + P[19][0]*SH_MAG[2] + P[19][1]*SH_MAG[1] + P[19][2]*SH_MAG[0] - P[19][3]*SK_MY[2] - P[19][17]*SK_MY[1] - P[19][16]*SK_MY[3] + P[19][18]*SK_MY[4]);
+            Kfusion[20] = SK_MY[0]*(P[20][20] + P[20][0]*SH_MAG[2] + P[20][1]*SH_MAG[1] + P[20][2]*SH_MAG[0] - P[20][3]*SK_MY[2] - P[20][17]*SK_MY[1] - P[20][16]*SK_MY[3] + P[20][18]*SK_MY[4]);
+            Kfusion[21] = SK_MY[0]*(P[21][20] + P[21][0]*SH_MAG[2] + P[21][1]*SH_MAG[1] + P[21][2]*SH_MAG[0] - P[21][3]*SK_MY[2] - P[21][17]*SK_MY[1] - P[21][16]*SK_MY[3] + P[21][18]*SK_MY[4]);
+            Kfusion[22] = SK_MY[0]*(P[22][20] + P[22][0]*SH_MAG[2] + P[22][1]*SH_MAG[1] + P[22][2]*SH_MAG[0] - P[22][3]*SK_MY[2] - P[22][17]*SK_MY[1] - P[22][16]*SK_MY[3] + P[22][18]*SK_MY[4]);
+            varInnovMag[1] = 1.0f/SK_MY[0];
+            innovMag[1] = MagPred[1] - magData.y;
+        }
+        else if (obsIndex == 2) // we are now fusing the Z measurement
+        {
+            // Calculate observation jacobians
+            for (uint8_t i = 0; i < n_states; i++) H_MAG[i] = 0;
+            H_MAG[0] = SH_MAG[1];
+            H_MAG[1] = 2*magN*q3 - 2*magE*q0 - 2*magD*q1;
+            H_MAG[2] = SH_MAG[7] + SH_MAG[8] - 2*magD*q2;
+            H_MAG[3] = SH_MAG[0];
+            H_MAG[16] = 2*q0*q2 + 2*q1*q3;
+            H_MAG[17] = 2*q2*q3 - 2*q0*q1;
+            H_MAG[18] = SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6];
+            H_MAG[21] = 1;
+
+            // Calculate Kalman gain
+            SK_MZ[0] = 1/(P[21][21] + R_MAG + P[0][21]*SH_MAG[1] + P[3][21]*SH_MAG[0] + P[18][21]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) - (2*magD*q1 + 2*magE*q0 - 2*magN*q3)*(P[21][1] + P[0][1]*SH_MAG[1] + P[3][1]*SH_MAG[0] + P[18][1]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[16][1]*(2*q0*q2 + 2*q1*q3) - P[17][1]*(2*q0*q1 - 2*q2*q3) - P[1][1]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][1]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + (SH_MAG[7] + SH_MAG[8] - 2*magD*q2)*(P[21][2] + P[0][2]*SH_MAG[1] + P[3][2]*SH_MAG[0] + P[18][2]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[16][2]*(2*q0*q2 + 2*q1*q3) - P[17][2]*(2*q0*q1 - 2*q2*q3) - P[1][2]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][2]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + SH_MAG[1]*(P[21][0] + P[0][0]*SH_MAG[1] + P[3][0]*SH_MAG[0] + P[18][0]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[16][0]*(2*q0*q2 + 2*q1*q3) - P[17][0]*(2*q0*q1 - 2*q2*q3) - P[1][0]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][0]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + SH_MAG[0]*(P[21][3] + P[0][3]*SH_MAG[1] + P[3][3]*SH_MAG[0] + P[18][3]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[16][3]*(2*q0*q2 + 2*q1*q3) - P[17][3]*(2*q0*q1 - 2*q2*q3) - P[1][3]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][3]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + (SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6])*(P[21][18] + P[0][18]*SH_MAG[1] + P[3][18]*SH_MAG[0] + P[18][18]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[16][18]*(2*q0*q2 + 2*q1*q3) - P[17][18]*(2*q0*q1 - 2*q2*q3) - P[1][18]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][18]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + P[16][21]*(2*q0*q2 + 2*q1*q3) - P[17][21]*(2*q0*q1 - 2*q2*q3) - P[1][21]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + (2*q0*q2 + 2*q1*q3)*(P[21][16] + P[0][16]*SH_MAG[1] + P[3][16]*SH_MAG[0] + P[18][16]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[16][16]*(2*q0*q2 + 2*q1*q3) - P[17][16]*(2*q0*q1 - 2*q2*q3) - P[1][16]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][16]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - (2*q0*q1 - 2*q2*q3)*(P[21][17] + P[0][17]*SH_MAG[1] + P[3][17]*SH_MAG[0] + P[18][17]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[16][17]*(2*q0*q2 + 2*q1*q3) - P[17][17]*(2*q0*q1 - 2*q2*q3) - P[1][17]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][17]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + P[2][21]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2));
+            SK_MZ[1] = SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6];
+            SK_MZ[2] = 2*magD*q1 + 2*magE*q0 - 2*magN*q3;
+            SK_MZ[3] = SH_MAG[7] + SH_MAG[8] - 2*magD*q2;
+            SK_MZ[4] = 2*q0*q1 - 2*q2*q3;
+            SK_MZ[5] = 2*q0*q2 + 2*q1*q3;
+            Kfusion[0] = SK_MZ[0]*(P[0][21] + P[0][0]*SH_MAG[1] + P[0][3]*SH_MAG[0] - P[0][1]*SK_MZ[2] + P[0][2]*SK_MZ[3] + P[0][18]*SK_MZ[1] + P[0][16]*SK_MZ[5] - P[0][17]*SK_MZ[4]);
+            Kfusion[1] = SK_MZ[0]*(P[1][21] + P[1][0]*SH_MAG[1] + P[1][3]*SH_MAG[0] - P[1][1]*SK_MZ[2] + P[1][2]*SK_MZ[3] + P[1][18]*SK_MZ[1] + P[1][16]*SK_MZ[5] - P[1][17]*SK_MZ[4]);
+            Kfusion[2] = SK_MZ[0]*(P[2][21] + P[2][0]*SH_MAG[1] + P[2][3]*SH_MAG[0] - P[2][1]*SK_MZ[2] + P[2][2]*SK_MZ[3] + P[2][18]*SK_MZ[1] + P[2][16]*SK_MZ[5] - P[2][17]*SK_MZ[4]);
+            Kfusion[3] = SK_MZ[0]*(P[3][21] + P[3][0]*SH_MAG[1] + P[3][3]*SH_MAG[0] - P[3][1]*SK_MZ[2] + P[3][2]*SK_MZ[3] + P[3][18]*SK_MZ[1] + P[3][16]*SK_MZ[5] - P[3][17]*SK_MZ[4]);
+            Kfusion[4] = SK_MZ[0]*(P[4][21] + P[4][0]*SH_MAG[1] + P[4][3]*SH_MAG[0] - P[4][1]*SK_MZ[2] + P[4][2]*SK_MZ[3] + P[4][18]*SK_MZ[1] + P[4][16]*SK_MZ[5] - P[4][17]*SK_MZ[4]);
+            Kfusion[5] = SK_MZ[0]*(P[5][21] + P[5][0]*SH_MAG[1] + P[5][3]*SH_MAG[0] - P[5][1]*SK_MZ[2] + P[5][2]*SK_MZ[3] + P[5][18]*SK_MZ[1] + P[5][16]*SK_MZ[5] - P[5][17]*SK_MZ[4]);
+            Kfusion[6] = SK_MZ[0]*(P[6][21] + P[6][0]*SH_MAG[1] + P[6][3]*SH_MAG[0] - P[6][1]*SK_MZ[2] + P[6][2]*SK_MZ[3] + P[6][18]*SK_MZ[1] + P[6][16]*SK_MZ[5] - P[6][17]*SK_MZ[4]);
+            Kfusion[7] = SK_MZ[0]*(P[7][21] + P[7][0]*SH_MAG[1] + P[7][3]*SH_MAG[0] - P[7][1]*SK_MZ[2] + P[7][2]*SK_MZ[3] + P[7][18]*SK_MZ[1] + P[7][16]*SK_MZ[5] - P[7][17]*SK_MZ[4]);
+            Kfusion[8] = SK_MZ[0]*(P[8][21] + P[8][0]*SH_MAG[1] + P[8][3]*SH_MAG[0] - P[8][1]*SK_MZ[2] + P[8][2]*SK_MZ[3] + P[8][18]*SK_MZ[1] + P[8][16]*SK_MZ[5] - P[8][17]*SK_MZ[4]);
+            Kfusion[9] = SK_MZ[0]*(P[9][21] + P[9][0]*SH_MAG[1] + P[9][3]*SH_MAG[0] - P[9][1]*SK_MZ[2] + P[9][2]*SK_MZ[3] + P[9][18]*SK_MZ[1] + P[9][16]*SK_MZ[5] - P[9][17]*SK_MZ[4]);
+            Kfusion[10] = SK_MZ[0]*(P[10][21] + P[10][0]*SH_MAG[1] + P[10][3]*SH_MAG[0] - P[10][1]*SK_MZ[2] + P[10][2]*SK_MZ[3] + P[10][18]*SK_MZ[1] + P[10][16]*SK_MZ[5] - P[10][17]*SK_MZ[4]);
+            Kfusion[11] = SK_MZ[0]*(P[11][21] + P[11][0]*SH_MAG[1] + P[11][3]*SH_MAG[0] - P[11][1]*SK_MZ[2] + P[11][2]*SK_MZ[3] + P[11][18]*SK_MZ[1] + P[11][16]*SK_MZ[5] - P[11][17]*SK_MZ[4]);
+            Kfusion[12] = SK_MZ[0]*(P[12][21] + P[12][0]*SH_MAG[1] + P[12][3]*SH_MAG[0] - P[12][1]*SK_MZ[2] + P[12][2]*SK_MZ[3] + P[12][18]*SK_MZ[1] + P[12][16]*SK_MZ[5] - P[12][17]*SK_MZ[4]);
+            // Only height measurements are allowed to modify the Z delta velocity bias state. This improves the stability of the estimate
+            Kfusion[13] = 0.0f;//SK_MZ[0]*(P[13][21] + P[13][0]*SH_MAG[1] + P[13][3]*SH_MAG[0] - P[13][1]*SK_MZ[2] + P[13][2]*SK_MZ[3] + P[13][18]*SK_MZ[1] + P[13][16]*SK_MZ[5] - P[13][17]*SK_MZ[4]);
+            Kfusion[14] = SK_MZ[0]*(P[14][21] + P[14][0]*SH_MAG[1] + P[14][3]*SH_MAG[0] - P[14][1]*SK_MZ[2] + P[14][2]*SK_MZ[3] + P[14][18]*SK_MZ[1] + P[14][16]*SK_MZ[5] - P[14][17]*SK_MZ[4]);
+            Kfusion[15] = SK_MZ[0]*(P[15][21] + P[15][0]*SH_MAG[1] + P[15][3]*SH_MAG[0] - P[15][1]*SK_MZ[2] + P[15][2]*SK_MZ[3] + P[15][18]*SK_MZ[1] + P[15][16]*SK_MZ[5] - P[15][17]*SK_MZ[4]);
+            Kfusion[16] = SK_MZ[0]*(P[16][21] + P[16][0]*SH_MAG[1] + P[16][3]*SH_MAG[0] - P[16][1]*SK_MZ[2] + P[16][2]*SK_MZ[3] + P[16][18]*SK_MZ[1] + P[16][16]*SK_MZ[5] - P[16][17]*SK_MZ[4]);
+            Kfusion[17] = SK_MZ[0]*(P[17][21] + P[17][0]*SH_MAG[1] + P[17][3]*SH_MAG[0] - P[17][1]*SK_MZ[2] + P[17][2]*SK_MZ[3] + P[17][18]*SK_MZ[1] + P[17][16]*SK_MZ[5] - P[17][17]*SK_MZ[4]);
+            Kfusion[18] = SK_MZ[0]*(P[18][21] + P[18][0]*SH_MAG[1] + P[18][3]*SH_MAG[0] - P[18][1]*SK_MZ[2] + P[18][2]*SK_MZ[3] + P[18][18]*SK_MZ[1] + P[18][16]*SK_MZ[5] - P[18][17]*SK_MZ[4]);
+            Kfusion[19] = SK_MZ[0]*(P[19][21] + P[19][0]*SH_MAG[1] + P[19][3]*SH_MAG[0] - P[19][1]*SK_MZ[2] + P[19][2]*SK_MZ[3] + P[19][18]*SK_MZ[1] + P[19][16]*SK_MZ[5] - P[19][17]*SK_MZ[4]);
+            Kfusion[20] = SK_MZ[0]*(P[20][21] + P[20][0]*SH_MAG[1] + P[20][3]*SH_MAG[0] - P[20][1]*SK_MZ[2] + P[20][2]*SK_MZ[3] + P[20][18]*SK_MZ[1] + P[20][16]*SK_MZ[5] - P[20][17]*SK_MZ[4]);
+            Kfusion[21] = SK_MZ[0]*(P[21][21] + P[21][0]*SH_MAG[1] + P[21][3]*SH_MAG[0] - P[21][1]*SK_MZ[2] + P[21][2]*SK_MZ[3] + P[21][18]*SK_MZ[1] + P[21][16]*SK_MZ[5] - P[21][17]*SK_MZ[4]);
+            Kfusion[22] = SK_MZ[0]*(P[22][21] + P[22][0]*SH_MAG[1] + P[22][3]*SH_MAG[0] - P[22][1]*SK_MZ[2] + P[22][2]*SK_MZ[3] + P[22][18]*SK_MZ[1] + P[22][16]*SK_MZ[5] - P[22][17]*SK_MZ[4]);
+            varInnovMag[2] = 1.0f/SK_MZ[0];
+            innovMag[2] = MagPred[2] - magData.z;
+
+        }
+
+        // Check the innovation for consistency and don't fuse if > 5Sigma
+        if ((innovMag[obsIndex]*innovMag[obsIndex]/varInnovMag[obsIndex]) < 25.0)
+        {
+            // correct the state vector
+            for (uint8_t j= 0; j<=indexLimit; j++)
+            {
+                states[j] = states[j] - Kfusion[j] * innovMag[obsIndex];
+            }
+            // normalise the quaternion states
+            float quatMag = sqrt(states[0]*states[0] + states[1]*states[1] + states[2]*states[2] + states[3]*states[3]);
+            if (quatMag > 1e-12)
+            {
+                for (uint8_t j= 0; j<=3; j++)
+                {
+                    float quatMagInv = 1.0f/quatMag;
+                    states[j] = states[j] * quatMagInv;
+                }
+            }
+            // correct the covariance P = (I - K*H)*P
+            // take advantage of the empty columns in KH to reduce the
+            // number of operations
+            for (uint8_t i = 0; i<=indexLimit; i++)
+            {
+                for (uint8_t j = 0; j <= 3; j++)
+                {
+                    KH[i][j] = Kfusion[i] * H_MAG[j];
+                }
+                for (uint8_t j = 4; j <= 15; j++) KH[i][j] = 0.0f;
+                if (!onGround)
+                {
+                    for (uint8_t j = 16; j <= 21; j++)
+                    {
+                        KH[i][j] = Kfusion[i] * H_MAG[j];
+                    }
+                }
+                else
+                {
+                    for (uint8_t j = 16; j <= 21; j++)
+                    {
+                        KH[i][j] = 0.0f;
+                    }
+                }
+            }
+            for (uint8_t i = 0; i<=indexLimit; i++)
+            {
+                for (uint8_t j = 0; j<=indexLimit; j++)
+                {
+                    KHP[i][j] = 0.0f;
+                    for (uint8_t k = 0; k <= 3; k++)
+                    {
+                        KHP[i][j] = KHP[i][j] + KH[i][k] * P[k][j];
+                    }
+                    if (!onGround)
+                    {
+                        for (uint8_t k = 16; k<=21; k++)
+                        {
+                            KHP[i][j] = KHP[i][j] + KH[i][k] * P[k][j];
+                        }
+                    }
+                }
+            }
+        }
+        for (uint8_t i = 0; i <= indexLimit; i++)
+        {
+            for (uint8_t j = 0; j <= indexLimit; j++)
+            {
+                P[i][j] = P[i][j] - KHP[i][j];
+            }
+        }
+    }
+    obsIndex = obsIndex + 1;
+
+    ForceSymmetry();
+    ConstrainVariances();
+}
+
+void AttPosEKF::FuseAirspeed()
+{
+    float vn;
+    float ve;
+    float vd;
+    float vwn;
+    float vwe;
+    float R_TAS = sq(airspeedMeasurementSigma);
+    float SH_TAS[3];
+    float VtasPred;
+
+    // Copy required states to local variable names
+    vn = statesAtVtasMeasTime[4];
+    ve = statesAtVtasMeasTime[5];
+    vd = statesAtVtasMeasTime[6];
+    vwn = statesAtVtasMeasTime[14];
+    vwe = statesAtVtasMeasTime[15];
+
+    // Need to check that it is flying before fusing airspeed data
+    // Calculate the predicted airspeed
+    VtasPred = sqrtf((ve - vwe)*(ve - vwe) + (vn - vwn)*(vn - vwn) + vd*vd);
+    // Perform fusion of True Airspeed measurement
+    if (useAirspeed && fuseVtasData && (VtasPred > 1.0f) && (VtasMeas > 8.0f))
+    {
+        // Calculate observation jacobians
+        SH_TAS[0] = 1/(sqrt(sq(ve - vwe) + sq(vn - vwn) + sq(vd)));
+        SH_TAS[1] = (SH_TAS[0]*(2.0f*ve - 2*vwe))/2.0f;
+        SH_TAS[2] = (SH_TAS[0]*(2.0f*vn - 2*vwn))/2.0f;
+        
+        float H_TAS[n_states];
+        for (uint8_t i = 0; i < n_states; i++) H_TAS[i] = 0.0f;
+        H_TAS[4] = SH_TAS[2];
+        H_TAS[5] = SH_TAS[1];
+        H_TAS[6] = vd*SH_TAS[0];
+        H_TAS[14] = -SH_TAS[2];
+        H_TAS[15] = -SH_TAS[1];
+
+        // Calculate Kalman gains
+        float SK_TAS = 1/(R_TAS + SH_TAS[2]*(P[4][4]*SH_TAS[2] + P[5][4]*SH_TAS[1] - P[14][4]*SH_TAS[2] - P[15][4]*SH_TAS[1] + P[6][4]*vd*SH_TAS[0]) + SH_TAS[1]*(P[4][5]*SH_TAS[2] + P[5][5]*SH_TAS[1] - P[14][5]*SH_TAS[2] - P[15][5]*SH_TAS[1] + P[6][5]*vd*SH_TAS[0]) - SH_TAS[2]*(P[4][14]*SH_TAS[2] + P[5][14]*SH_TAS[1] - P[14][14]*SH_TAS[2] - P[15][14]*SH_TAS[1] + P[6][14]*vd*SH_TAS[0]) - SH_TAS[1]*(P[4][15]*SH_TAS[2] + P[5][15]*SH_TAS[1] - P[14][15]*SH_TAS[2] - P[15][15]*SH_TAS[1] + P[6][15]*vd*SH_TAS[0]) + vd*SH_TAS[0]*(P[4][6]*SH_TAS[2] + P[5][6]*SH_TAS[1] - P[14][6]*SH_TAS[2] - P[15][6]*SH_TAS[1] + P[6][6]*vd*SH_TAS[0]));
+        Kfusion[0] = SK_TAS*(P[0][4]*SH_TAS[2] - P[0][14]*SH_TAS[2] + P[0][5]*SH_TAS[1] - P[0][15]*SH_TAS[1] + P[0][6]*vd*SH_TAS[0]);
+        Kfusion[1] = SK_TAS*(P[1][4]*SH_TAS[2] - P[1][14]*SH_TAS[2] + P[1][5]*SH_TAS[1] - P[1][15]*SH_TAS[1] + P[1][6]*vd*SH_TAS[0]);
+        Kfusion[2] = SK_TAS*(P[2][4]*SH_TAS[2] - P[2][14]*SH_TAS[2] + P[2][5]*SH_TAS[1] - P[2][15]*SH_TAS[1] + P[2][6]*vd*SH_TAS[0]);
+        Kfusion[3] = SK_TAS*(P[3][4]*SH_TAS[2] - P[3][14]*SH_TAS[2] + P[3][5]*SH_TAS[1] - P[3][15]*SH_TAS[1] + P[3][6]*vd*SH_TAS[0]);
+        Kfusion[4] = SK_TAS*(P[4][4]*SH_TAS[2] - P[4][14]*SH_TAS[2] + P[4][5]*SH_TAS[1] - P[4][15]*SH_TAS[1] + P[4][6]*vd*SH_TAS[0]);
+        Kfusion[5] = SK_TAS*(P[5][4]*SH_TAS[2] - P[5][14]*SH_TAS[2] + P[5][5]*SH_TAS[1] - P[5][15]*SH_TAS[1] + P[5][6]*vd*SH_TAS[0]);
+        Kfusion[6] = SK_TAS*(P[6][4]*SH_TAS[2] - P[6][14]*SH_TAS[2] + P[6][5]*SH_TAS[1] - P[6][15]*SH_TAS[1] + P[6][6]*vd*SH_TAS[0]);
+        Kfusion[7] = SK_TAS*(P[7][4]*SH_TAS[2] - P[7][14]*SH_TAS[2] + P[7][5]*SH_TAS[1] - P[7][15]*SH_TAS[1] + P[7][6]*vd*SH_TAS[0]);
+        Kfusion[8] = SK_TAS*(P[8][4]*SH_TAS[2] - P[8][14]*SH_TAS[2] + P[8][5]*SH_TAS[1] - P[8][15]*SH_TAS[1] + P[8][6]*vd*SH_TAS[0]);
+        Kfusion[9] = SK_TAS*(P[9][4]*SH_TAS[2] - P[9][14]*SH_TAS[2] + P[9][5]*SH_TAS[1] - P[9][15]*SH_TAS[1] + P[9][6]*vd*SH_TAS[0]);
+        Kfusion[10] = SK_TAS*(P[10][4]*SH_TAS[2] - P[10][14]*SH_TAS[2] + P[10][5]*SH_TAS[1] - P[10][15]*SH_TAS[1] + P[10][6]*vd*SH_TAS[0]);
+        Kfusion[11] = SK_TAS*(P[11][4]*SH_TAS[2] - P[11][14]*SH_TAS[2] + P[11][5]*SH_TAS[1] - P[11][15]*SH_TAS[1] + P[11][6]*vd*SH_TAS[0]);
+        Kfusion[12] = SK_TAS*(P[12][4]*SH_TAS[2] - P[12][14]*SH_TAS[2] + P[12][5]*SH_TAS[1] - P[12][15]*SH_TAS[1] + P[12][6]*vd*SH_TAS[0]);
+        // Only height measurements are allowed to modify the Z delta velocity bias state. This improves the stability of the estimate
+        Kfusion[13] = 0.0f;//SK_TAS*(P[13][4]*SH_TAS[2] - P[13][14]*SH_TAS[2] + P[13][5]*SH_TAS[1] - P[13][15]*SH_TAS[1] + P[13][6]*vd*SH_TAS[0]);
+        Kfusion[14] = SK_TAS*(P[14][4]*SH_TAS[2] - P[14][14]*SH_TAS[2] + P[14][5]*SH_TAS[1] - P[14][15]*SH_TAS[1] + P[14][6]*vd*SH_TAS[0]);
+        Kfusion[15] = SK_TAS*(P[15][4]*SH_TAS[2] - P[15][14]*SH_TAS[2] + P[15][5]*SH_TAS[1] - P[15][15]*SH_TAS[1] + P[15][6]*vd*SH_TAS[0]);
+        Kfusion[16] = SK_TAS*(P[16][4]*SH_TAS[2] - P[16][14]*SH_TAS[2] + P[16][5]*SH_TAS[1] - P[16][15]*SH_TAS[1] + P[16][6]*vd*SH_TAS[0]);
+        Kfusion[17] = SK_TAS*(P[17][4]*SH_TAS[2] - P[17][14]*SH_TAS[2] + P[17][5]*SH_TAS[1] - P[17][15]*SH_TAS[1] + P[17][6]*vd*SH_TAS[0]);
+        Kfusion[18] = SK_TAS*(P[18][4]*SH_TAS[2] - P[18][14]*SH_TAS[2] + P[18][5]*SH_TAS[1] - P[18][15]*SH_TAS[1] + P[18][6]*vd*SH_TAS[0]);
+        Kfusion[19] = SK_TAS*(P[19][4]*SH_TAS[2] - P[19][14]*SH_TAS[2] + P[19][5]*SH_TAS[1] - P[19][15]*SH_TAS[1] + P[19][6]*vd*SH_TAS[0]);
+        Kfusion[20] = SK_TAS*(P[20][4]*SH_TAS[2] - P[20][14]*SH_TAS[2] + P[20][5]*SH_TAS[1] - P[20][15]*SH_TAS[1] + P[20][6]*vd*SH_TAS[0]);
+        Kfusion[21] = SK_TAS*(P[21][4]*SH_TAS[2] - P[21][14]*SH_TAS[2] + P[21][5]*SH_TAS[1] - P[21][15]*SH_TAS[1] + P[21][6]*vd*SH_TAS[0]);
+        Kfusion[22] = SK_TAS*(P[22][4]*SH_TAS[2] - P[22][14]*SH_TAS[2] + P[22][5]*SH_TAS[1] - P[22][15]*SH_TAS[1] + P[22][6]*vd*SH_TAS[0]);
+        varInnovVtas = 1.0f/SK_TAS;
+
+        // Calculate the measurement innovation
+        innovVtas = VtasPred - VtasMeas;
+        // Check the innovation for consistency and don't fuse if > 5Sigma
+        if ((innovVtas*innovVtas*SK_TAS) < 25.0)
+        {
+            // correct the state vector
+            for (uint8_t j=0; j <= 22; j++)
+            {
+                states[j] = states[j] - Kfusion[j] * innovVtas;
+            }
+            // normalise the quaternion states
+            float quatMag = sqrt(states[0]*states[0] + states[1]*states[1] + states[2]*states[2] + states[3]*states[3]);
+            if (quatMag > 1e-12f)
+            {
+                for (uint8_t j= 0; j <= 3; j++)
+                {
+                    float quatMagInv = 1.0f/quatMag;
+                    states[j] = states[j] * quatMagInv;
+                }
+            }
+            // correct the covariance P = (I - K*H)*P
+            // take advantage of the empty columns in H to reduce the
+            // number of operations
+            for (uint8_t i = 0; i <= 22; i++)
+            {
+                for (uint8_t j = 0; j <= 3; j++) KH[i][j] = 0.0;
+                for (uint8_t j = 4; j <= 6; j++)
+                {
+                    KH[i][j] = Kfusion[i] * H_TAS[j];
+                }
+                for (uint8_t j = 7; j <= 13; j++) KH[i][j] = 0.0;
+                for (uint8_t j = 14; j <= 15; j++)
+                {
+                    KH[i][j] = Kfusion[i] * H_TAS[j];
+                }
+                for (uint8_t j = 16; j <= 22; j++) KH[i][j] = 0.0;
+            }
+            for (uint8_t i = 0; i <= 22; i++)
+            {
+                for (uint8_t j = 0; j <= 22; j++)
+                {
+                    KHP[i][j] = 0.0;
+                    for (uint8_t k = 4; k <= 6; k++)
+                    {
+                        KHP[i][j] = KHP[i][j] + KH[i][k] * P[k][j];
+                    }
+                    for (uint8_t k = 14; k <= 15; k++)
+                    {
+                        KHP[i][j] = KHP[i][j] + KH[i][k] * P[k][j];
+                    }
+                }
+            }
+            for (uint8_t i = 0; i <= 22; i++)
+            {
+                for (uint8_t j = 0; j <= 22; j++)
+                {
+                    P[i][j] = P[i][j] - KHP[i][j];
+                }
+            }
+        }
+    }
+
+    ForceSymmetry();
+    ConstrainVariances();
+}
+
+void AttPosEKF::zeroRows(float (&covMat)[n_states][n_states], uint8_t first, uint8_t last)
+{
+    uint8_t row;
+    uint8_t col;
+    for (row=first; row<=last; row++)
+    {
+        for (col=0; col<n_states; col++)
+        {
+            covMat[row][col] = 0.0;
+        }
+    }
+}
+
+void AttPosEKF::FuseRangeFinder()
+{
+
+    // Local variables
+    float rngPred;
+    float SH_RNG[5];
+    float H_RNG[23];
+    float SK_RNG[6];
+    float cosRngTilt;
+    const float R_RNG = 0.25f; // 0.5 m2 rangefinder measurement variance
+
+    // Copy required states to local variable names
+    float q0 = statesAtRngTime[0];
+    float q1 = statesAtRngTime[1];
+    float q2 = statesAtRngTime[2];
+    float q3 = statesAtRngTime[3];
+    float pd = statesAtRngTime[9];
+    float ptd = statesAtRngTime[22];
+
+    // Need to check that our range finder tilt angle is less than 30 degrees and we are using range finder data
+    SH_RNG[4] = sin(rngFinderPitch);
+    cosRngTilt = - Tbn.z.x * SH_RNG[4] + Tbn.z.z * cos(rngFinderPitch);
+    if (useRangeFinder && cosRngTilt > 0.87f)
+    {
+        // Calculate observation jacobian and Kalman gain ignoring all states other than the terrain offset
+        // This prevents the range finder measurement modifying any of the other filter states and significantly reduces computations
+        SH_RNG[0] = SH_RNG[4]*(2*q0*q2 - 2*q1*q3) - sq(q0) + sq(q1) + sq(q2) - sq(q3);
+        SH_RNG[1] = pd - ptd;
+        SH_RNG[2] = 1/sq(SH_RNG[0]);
+        SH_RNG[3] = 1/SH_RNG[0];
+        for (uint8_t i = 0; i < n_states; i++) {
+            H_RNG[i] = 0.0f;
+            Kfusion[i] = 0.0f;
+        }
+        H_RNG[22] = -SH_RNG[3];
+        SK_RNG[0] = 1/(R_RNG + SH_RNG[3]*(P[9][9]*SH_RNG[3] - P[22][9]*SH_RNG[3] + P[0][9]*SH_RNG[1]*SH_RNG[2]*(2*q0 - 2*q2*SH_RNG[4]) - P[1][9]*SH_RNG[1]*SH_RNG[2]*(2*q1 - 2*q3*SH_RNG[4]) - P[2][9]*SH_RNG[1]*SH_RNG[2]*(2*q2 + 2*q0*SH_RNG[4]) + P[3][9]*SH_RNG[1]*SH_RNG[2]*(2*q3 + 2*q1*SH_RNG[4])) - SH_RNG[3]*(P[9][22]*SH_RNG[3] - P[22][22]*SH_RNG[3] + P[0][22]*SH_RNG[1]*SH_RNG[2]*(2*q0 - 2*q2*SH_RNG[4]) - P[1][22]*SH_RNG[1]*SH_RNG[2]*(2*q1 - 2*q3*SH_RNG[4]) - P[2][22]*SH_RNG[1]*SH_RNG[2]*(2*q2 + 2*q0*SH_RNG[4]) + P[3][22]*SH_RNG[1]*SH_RNG[2]*(2*q3 + 2*q1*SH_RNG[4])) + SH_RNG[1]*SH_RNG[2]*(2*q0 - 2*q2*SH_RNG[4])*(P[9][0]*SH_RNG[3] - P[22][0]*SH_RNG[3] + P[0][0]*SH_RNG[1]*SH_RNG[2]*(2*q0 - 2*q2*SH_RNG[4]) - P[1][0]*SH_RNG[1]*SH_RNG[2]*(2*q1 - 2*q3*SH_RNG[4]) - P[2][0]*SH_RNG[1]*SH_RNG[2]*(2*q2 + 2*q0*SH_RNG[4]) + P[3][0]*SH_RNG[1]*SH_RNG[2]*(2*q3 + 2*q1*SH_RNG[4])) - SH_RNG[1]*SH_RNG[2]*(2*q1 - 2*q3*SH_RNG[4])*(P[9][1]*SH_RNG[3] - P[22][1]*SH_RNG[3] + P[0][1]*SH_RNG[1]*SH_RNG[2]*(2*q0 - 2*q2*SH_RNG[4]) - P[1][1]*SH_RNG[1]*SH_RNG[2]*(2*q1 - 2*q3*SH_RNG[4]) - P[2][1]*SH_RNG[1]*SH_RNG[2]*(2*q2 + 2*q0*SH_RNG[4]) + P[3][1]*SH_RNG[1]*SH_RNG[2]*(2*q3 + 2*q1*SH_RNG[4])) - SH_RNG[1]*SH_RNG[2]*(2*q2 + 2*q0*SH_RNG[4])*(P[9][2]*SH_RNG[3] - P[22][2]*SH_RNG[3] + P[0][2]*SH_RNG[1]*SH_RNG[2]*(2*q0 - 2*q2*SH_RNG[4]) - P[1][2]*SH_RNG[1]*SH_RNG[2]*(2*q1 - 2*q3*SH_RNG[4]) - P[2][2]*SH_RNG[1]*SH_RNG[2]*(2*q2 + 2*q0*SH_RNG[4]) + P[3][2]*SH_RNG[1]*SH_RNG[2]*(2*q3 + 2*q1*SH_RNG[4])) + SH_RNG[1]*SH_RNG[2]*(2*q3 + 2*q1*SH_RNG[4])*(P[9][3]*SH_RNG[3] - P[22][3]*SH_RNG[3] + P[0][3]*SH_RNG[1]*SH_RNG[2]*(2*q0 - 2*q2*SH_RNG[4]) - P[1][3]*SH_RNG[1]*SH_RNG[2]*(2*q1 - 2*q3*SH_RNG[4]) - P[2][3]*SH_RNG[1]*SH_RNG[2]*(2*q2 + 2*q0*SH_RNG[4]) + P[3][3]*SH_RNG[1]*SH_RNG[2]*(2*q3 + 2*q1*SH_RNG[4])));
+        SK_RNG[1] = 2*q1 - 2*q3*SH_RNG[4];
+        SK_RNG[2] = 2*q0 - 2*q2*SH_RNG[4];
+        SK_RNG[3] = 2*q3 + 2*q1*SH_RNG[4];
+        SK_RNG[4] = 2*q2 + 2*q0*SH_RNG[4];
+        SK_RNG[5] = SH_RNG[2];
+        Kfusion[22] = SK_RNG[0]*(P[22][9]*SH_RNG[3] - P[22][22]*SH_RNG[3] + P[22][0]*SH_RNG[1]*SK_RNG[2]*SK_RNG[5] - P[22][1]*SH_RNG[1]*SK_RNG[1]*SK_RNG[5] - P[22][2]*SH_RNG[1]*SK_RNG[4]*SK_RNG[5] + P[22][3]*SH_RNG[1]*SK_RNG[3]*SK_RNG[5]);
+
+        // Calculate the measurement innovation
+        rngPred = (ptd - pd)/cosRngTilt;
+        innovRng = rngPred - rngMea;
+        //printf("mea=%5.1f, pred=%5.1f, pd=%5.1f, ptd=%5.2f\n", rngMea, rngPred, pd, ptd);
+
+        // Check the innovation for consistency and don't fuse if > 5Sigma
+        if ((innovRng*innovRng*SK_RNG[0]) < 25)
+        {
+            // correct the state vector
+            states[22] = states[22] - Kfusion[22] * innovRng;
+
+            // correct the covariance P = (I - K*H)*P
+            P[22][22] = P[22][22] - Kfusion[22] * H_RNG[22] * P[22][22];
+            P[22][22] = ConstrainFloat(P[22][22], 0.0f, 10000.0f);
+        }
+    }
+
+}
+
+void AttPosEKF::zeroCols(float (&covMat)[n_states][n_states], uint8_t first, uint8_t last)
+{
+    uint8_t row;
+    uint8_t col;
+    for (col=first; col<=last; col++)
+    {
+        for (row=0; row < n_states; row++)
+        {
+            covMat[row][col] = 0.0;
+        }
+    }
+}
+
+float AttPosEKF::sq(float valIn)
+{
+    return valIn*valIn;
+}
+
+// Store states in a history array along with time stamp
+void AttPosEKF::StoreStates(uint64_t timestamp_ms)
+{
+    for (unsigned i=0; i<n_states; i++)
+        storedStates[i][storeIndex] = states[i];
+    statetimeStamp[storeIndex] = timestamp_ms;
+    storeIndex++;
+    if (storeIndex == data_buffer_size)
+        storeIndex = 0;
+}
+
+void AttPosEKF::ResetStoredStates()
+{
+    // reset all stored states
+    memset(&storedStates[0][0], 0, sizeof(storedStates));
+    memset(&statetimeStamp[0], 0, sizeof(statetimeStamp));
+
+    // reset store index to first
+    storeIndex = 0;
+
+    // overwrite all existing states
+    for (unsigned i = 0; i < n_states; i++) {
+        storedStates[i][storeIndex] = states[i];
+    }
+
+    statetimeStamp[storeIndex] = millis();
+
+    // increment to next storage index
+    storeIndex++;
+}
+
+// Output the state vector stored at the time that best matches that specified by msec
+int AttPosEKF::RecallStates(float* statesForFusion, uint64_t msec)
+{
+    int ret = 0;
+
+    int64_t bestTimeDelta = 200;
+    unsigned bestStoreIndex = 0;
+    for (unsigned storeIndex = 0; storeIndex < data_buffer_size; storeIndex++)
+    {
+        // Work around a GCC compiler bug - we know 64bit support on ARM is
+        // sketchy in GCC.
+        uint64_t timeDelta;
+
+        if (msec > statetimeStamp[storeIndex]) {
+            timeDelta = msec - statetimeStamp[storeIndex];
+        } else {
+            timeDelta = statetimeStamp[storeIndex] - msec;
+        }
+
+        if (timeDelta < bestTimeDelta)
+        {
+            bestStoreIndex = storeIndex;
+            bestTimeDelta = timeDelta;
+        }
+    }
+    if (bestTimeDelta < 200) // only output stored state if < 200 msec retrieval error
+    {
+        for (unsigned i=0; i < n_states; i++) {
+            if (isfinite(storedStates[i][bestStoreIndex])) {
+                statesForFusion[i] = storedStates[i][bestStoreIndex];
+            } else if (isfinite(states[i])) {
+                statesForFusion[i] = states[i];
+            } else {
+                // There is not much we can do here, except reporting the error we just
+                // found.
+                ret++;
+            }
+        }
+    }
+    else // otherwise output current state
+    {
+        for (unsigned i = 0; i < n_states; i++) {
+            if (isfinite(states[i])) {
+                statesForFusion[i] = states[i];
+            } else {
+                ret++;
+            }
+        }
+    }
+
+    return ret;
+}
+
+void AttPosEKF::quat2Tnb(Mat3f &Tnb, const float (&quat)[4])
+{
+    // Calculate the nav to body cosine matrix
+    float q00 = sq(quat[0]);
+    float q11 = sq(quat[1]);
+    float q22 = sq(quat[2]);
+    float q33 = sq(quat[3]);
+    float q01 =  quat[0]*quat[1];
+    float q02 =  quat[0]*quat[2];
+    float q03 =  quat[0]*quat[3];
+    float q12 =  quat[1]*quat[2];
+    float q13 =  quat[1]*quat[3];
+    float q23 =  quat[2]*quat[3];
+
+    Tnb.x.x = q00 + q11 - q22 - q33;
+    Tnb.y.y = q00 - q11 + q22 - q33;
+    Tnb.z.z = q00 - q11 - q22 + q33;
+    Tnb.y.x = 2*(q12 - q03);
+    Tnb.z.x = 2*(q13 + q02);
+    Tnb.x.y = 2*(q12 + q03);
+    Tnb.z.y = 2*(q23 - q01);
+    Tnb.x.z = 2*(q13 - q02);
+    Tnb.y.z = 2*(q23 + q01);
+}
+
+void AttPosEKF::quat2Tbn(Mat3f &Tbn, const float (&quat)[4])
+{
+    // Calculate the body to nav cosine matrix
+    float q00 = sq(quat[0]);
+    float q11 = sq(quat[1]);
+    float q22 = sq(quat[2]);
+    float q33 = sq(quat[3]);
+    float q01 =  quat[0]*quat[1];
+    float q02 =  quat[0]*quat[2];
+    float q03 =  quat[0]*quat[3];
+    float q12 =  quat[1]*quat[2];
+    float q13 =  quat[1]*quat[3];
+    float q23 =  quat[2]*quat[3];
+
+    Tbn.x.x = q00 + q11 - q22 - q33;
+    Tbn.y.y = q00 - q11 + q22 - q33;
+    Tbn.z.z = q00 - q11 - q22 + q33;
+    Tbn.x.y = 2*(q12 - q03);
+    Tbn.x.z = 2*(q13 + q02);
+    Tbn.y.x = 2*(q12 + q03);
+    Tbn.y.z = 2*(q23 - q01);
+    Tbn.z.x = 2*(q13 - q02);
+    Tbn.z.y = 2*(q23 + q01);
+}
+
+void AttPosEKF::eul2quat(float (&quat)[4], const float (&eul)[3])
+{
+    float u1 = cos(0.5f*eul[0]);
+    float u2 = cos(0.5f*eul[1]);
+    float u3 = cos(0.5f*eul[2]);
+    float u4 = sin(0.5f*eul[0]);
+    float u5 = sin(0.5f*eul[1]);
+    float u6 = sin(0.5f*eul[2]);
+    quat[0] = u1*u2*u3+u4*u5*u6;
+    quat[1] = u4*u2*u3-u1*u5*u6;
+    quat[2] = u1*u5*u3+u4*u2*u6;
+    quat[3] = u1*u2*u6-u4*u5*u3;
+}
+
+void AttPosEKF::quat2eul(float (&y)[3], const float (&u)[4])
+{
+    y[0] = atan2f((2.0f*(u[2]*u[3]+u[0]*u[1])) , (u[0]*u[0]-u[1]*u[1]-u[2]*u[2]+u[3]*u[3]));
+    y[1] = -asinf(2.0f*(u[1]*u[3]-u[0]*u[2]));
+    y[2] = atan2f((2.0f*(u[1]*u[2]+u[0]*u[3])) , (u[0]*u[0]+u[1]*u[1]-u[2]*u[2]-u[3]*u[3]));
+}
+
+void AttPosEKF::calcvelNED(float (&velNED)[3], float gpsCourse, float gpsGndSpd, float gpsVelD)
+{
+    velNED[0] = gpsGndSpd*cosf(gpsCourse);
+    velNED[1] = gpsGndSpd*sinf(gpsCourse);
+    velNED[2] = gpsVelD;
+}
+
+void AttPosEKF::calcposNED(float (&posNED)[3], double lat, double lon, float hgt, double latRef, double lonRef, float hgtRef)
+{
+    posNED[0] = earthRadius * (lat - latRef);
+    posNED[1] = earthRadius * cos(latRef) * (lon - lonRef);
+    posNED[2] = -(hgt - hgtRef);
+}
+
+void AttPosEKF::calcLLH(float (&posNED)[3], float lat, float lon, float hgt, float latRef, float lonRef, float hgtRef)
+{
+    lat = latRef + posNED[0] * earthRadiusInv;
+    lon = lonRef + posNED[1] * earthRadiusInv / cos(latRef);
+    hgt = hgtRef - posNED[2];
+}
+
+void AttPosEKF::OnGroundCheck()
+{
+    onGround = (((sq(velNED[0]) + sq(velNED[1]) + sq(velNED[2])) < 4.0f) && (VtasMeas < 6.0f));
+    if (staticMode) {
+        staticMode = (!refSet || (GPSstatus < GPS_FIX_3D));
+    }
+}
+
+void AttPosEKF::calcEarthRateNED(Vector3f &omega, float latitude)
+{
+    //Define Earth rotation vector in the NED navigation frame
+    omega.x  = earthRate*cosf(latitude);
+    omega.y  = 0.0f;
+    omega.z  = -earthRate*sinf(latitude);
+}
+
+void AttPosEKF::CovarianceInit()
+{
+    // Calculate the initial covariance matrix P
+    P[0][0]   = 0.25f * sq(1.0f*deg2rad);
+    P[1][1]   = 0.25f * sq(1.0f*deg2rad);
+    P[2][2]   = 0.25f * sq(1.0f*deg2rad);
+    P[3][3]   = 0.25f * sq(10.0f*deg2rad);
+    P[4][4]   = sq(0.7f);
+    P[5][5]   = P[4][4];
+    P[6][6]   = sq(0.7f);
+    P[7][7]   = sq(15.0f);
+    P[8][8]   = P[7][7];
+    P[9][9]   = sq(5.0f);
+    P[10][10] = sq(0.1f*deg2rad*dtIMU);
+    P[11][11] = P[10][10];
+    P[12][12] = P[10][10];
+    P[13][13] = sq(0.2f*dtIMU);
+    P[14][14] = sq(8.0f);
+    P[15][14]  = P[14][14];
+    P[16][16] = sq(0.02f);
+    P[17][17] = P[16][16];
+    P[18][18] = P[16][16];
+    P[19][19] = sq(0.02f);
+    P[20][20] = P[19][19];
+    P[21][21] = P[19][19];
+    P[22][22] = sq(0.5f);
+}
+
+float AttPosEKF::ConstrainFloat(float val, float min, float max)
+{
+    return (val > max) ? max : ((val < min) ? min : val);
+}
+
+void AttPosEKF::ConstrainVariances()
+{
+    if (!numericalProtection) {
+        return;
+    }
+
+    // State vector:
+    // 0-3: quaternions (q0, q1, q2, q3)
+    // 4-6: Velocity - m/sec (North, East, Down)
+    // 7-9: Position - m (North, East, Down)
+    // 10-12: Delta Angle bias - rad (X,Y,Z)
+    // 13: Delta Velocity bias - m/s (Z)
+    // 14-15: Wind Vector  - m/sec (North,East)
+    // 16-18: Earth Magnetic Field Vector - gauss (North, East, Down)
+    // 19-21: Body Magnetic Field Vector - gauss (X,Y,Z)
+    // 22: Terrain  offset - m
+
+    // Constrain quaternion variances
+    for (unsigned i = 0; i <= 3; i++) {
+        P[i][i] = ConstrainFloat(P[i][i], 0.0f, 1.0f);
+    }
+
+    // Constrain velocity variances
+    for (unsigned i = 4; i <= 6; i++) {
+        P[i][i] = ConstrainFloat(P[i][i], 0.0f, 1.0e3f);
+    }
+
+    // Constrain position variances
+    for (unsigned i = 7; i <= 9; i++) {
+        P[i][i] = ConstrainFloat(P[i][i], 0.0f, 1.0e6f);
+    }
+
+    // Constrain delta angle bias variances
+    for (unsigned i = 10; i <= 12; i++) {
+        P[i][i] = ConstrainFloat(P[i][i], 0.0f, sq(0.12f * dtIMU));
+    }
+
+    // Constrain delta velocity bias variance
+    P[13][13] = ConstrainFloat(P[13][13], 0.0f, sq(1.0f * dtIMU));
+
+    // Wind velocity variances
+    for (unsigned i = 14; i <= 15; i++) {
+        P[i][i] = ConstrainFloat(P[i][i], 0.0f, 1.0e3f);
+    }
+
+    // Earth magnetic field variances
+    for (unsigned i = 16; i <= 18; i++) {
+        P[i][i] = ConstrainFloat(P[i][i], 0.0f, 1.0f);
+    }
+
+    // Body magnetic field variances
+    for (unsigned i = 19; i <= 21; i++) {
+        P[i][i] = ConstrainFloat(P[i][i], 0.0f, 1.0f);
+    }
+
+    // Constrain terrain offset variance
+    P[22][22] = ConstrainFloat(P[22][22], 0.0f, 10000.0f);
+}
+
+void AttPosEKF::ConstrainStates()
+{
+    if (!numericalProtection) {
+        return;
+    }
+
+    // State vector:
+    // 0-3: quaternions (q0, q1, q2, q3)
+    // 4-6: Velocity - m/sec (North, East, Down)
+    // 7-9: Position - m (North, East, Down)
+    // 10-12: Delta Angle bias - rad (X,Y,Z)
+    // 13: Delta Velocity bias - m/s (Z)
+    // 14-15: Wind Vector  - m/sec (North,East)
+    // 16-18: Earth Magnetic Field Vector - gauss (North, East, Down)
+    // 19-21: Body Magnetic Field Vector - gauss (X,Y,Z)
+    // 22: Terrain  offset - m
+
+    // Constrain quaternion
+    for (unsigned i = 0; i <= 3; i++) {
+        states[i] = ConstrainFloat(states[i], -1.0f, 1.0f);
+    }
+
+    // Constrain velocities to what GPS can do for us
+    for (unsigned i = 4; i <= 6; i++) {
+        states[i] = ConstrainFloat(states[i], -5.0e2f, 5.0e2f);
+    }
+
+    // Constrain position to a reasonable vehicle range (in meters)
+    for (unsigned i = 7; i <= 8; i++) {
+        states[i] = ConstrainFloat(states[i], -1.0e6f, 1.0e6f);
+    }
+
+    // Constrain altitude
+    states[9] = ConstrainFloat(states[9], -4.0e4f, 1.0e4f);
+
+    // Angle bias limit - set to 8 degrees / sec
+    for (unsigned i = 10; i <= 12; i++) {
+        states[i] = ConstrainFloat(states[i], -0.12f * dtIMU, 0.12f * dtIMU);
+    }
+
+    // Constrain delta velocity bias
+    states[13] = ConstrainFloat(states[13], -1.0f * dtIMU, 1.0f * dtIMU);
+
+    // Wind velocity limits - assume 120 m/s max velocity
+    for (unsigned i = 14; i <= 15; i++) {
+        states[i] = ConstrainFloat(states[i], -120.0f, 120.0f);
+    }
+
+    // Earth magnetic field limits (in Gauss)
+    for (unsigned i = 16; i <= 18; i++) {
+        states[i] = ConstrainFloat(states[i], -1.0f, 1.0f);
+    }
+
+    // Body magnetic field variances (in Gauss).
+    // the max offset should be in this range.
+    for (unsigned i = 19; i <= 21; i++) {
+        states[i] = ConstrainFloat(states[i], -0.5f, 0.5f);
+    }
+
+    // Constrain terrain offset
+    states[22] = ConstrainFloat(states[22], -1000.0f, 1000.0f);
+
+}
+
+void AttPosEKF::ForceSymmetry()
+{
+    if (!numericalProtection) {
+        return;
+    }
+
+    // Force symmetry on the covariance matrix to prevent ill-conditioning
+    // of the matrix which would cause the filter to blow-up
+    for (unsigned i = 1; i < n_states; i++)
+    {
+        for (uint8_t j = 0; j < i; j++)
+        {
+            P[i][j] = 0.5f * (P[i][j] + P[j][i]);
+            P[j][i] = P[i][j];
+        }
+    }
+}
+
+bool AttPosEKF::FilterHealthy()
+{
+    if (!statesInitialised) {
+        return false;
+    }
+
+    // XXX Check state vector for NaNs and ill-conditioning
+
+    // Check if any of the major inputs timed out
+    if (current_ekf_state.posTimeout || current_ekf_state.velTimeout || current_ekf_state.hgtTimeout) {
+        return false;
+    }
+
+    // Nothing fired, return ok.
+    return true;
+}
+
+/**
+ * Reset the filter position states
+ *
+ * This resets the position to the last GPS measurement
+ * or to zero in case of static position.
+ */
+void AttPosEKF::ResetPosition(void)
+{
+    if (staticMode) {
+        states[7] = 0;
+        states[8] = 0;
+    } else if (GPSstatus >= GPS_FIX_3D) {
+
+        // reset the states from the GPS measurements
+        states[7] = posNE[0];
+        states[8] = posNE[1];
+    }
+}
+
+/**
+ * Reset the height state.
+ *
+ * This resets the height state with the last altitude measurements
+ */
+void AttPosEKF::ResetHeight(void)
+{
+    // write to the state vector
+    states[9]   = -hgtMea;
+}
+
+/**
+ * Reset the velocity state.
+ */
+void AttPosEKF::ResetVelocity(void)
+{
+    if (staticMode) {
+        states[4] = 0.0f;
+        states[5] = 0.0f;
+        states[6] = 0.0f;
+    } else if (GPSstatus >= GPS_FIX_3D) {
+
+        states[4]  = velNED[0]; // north velocity from last reading
+        states[5]  = velNED[1]; // east velocity from last reading
+        states[6]  = velNED[2]; // down velocity from last reading
+    }
+}
+
+
+void AttPosEKF::FillErrorReport(struct ekf_status_report *err)
+{
+    for (unsigned i = 0; i < n_states; i++)
+    {
+        err->states[i] = states[i];
+    }
+
+    err->velHealth = current_ekf_state.velHealth;
+    err->posHealth = current_ekf_state.posHealth;
+    err->hgtHealth = current_ekf_state.hgtHealth;
+    err->velTimeout = current_ekf_state.velTimeout;
+    err->posTimeout = current_ekf_state.posTimeout;
+    err->hgtTimeout = current_ekf_state.hgtTimeout;
+}
+
+bool AttPosEKF::StatesNaN(struct ekf_status_report *err_report) {
+    bool err = false;
+
+    // check all integrators
+    if (!isfinite(summedDelAng.x) || !isfinite(summedDelAng.y) || !isfinite(summedDelAng.z)) {
+        err_report->statesNaN = true;
+        ekf_debug("summedDelAng NaN: x: %f y: %f z: %f", (double)summedDelAng.x, (double)summedDelAng.y, (double)summedDelAng.z);
+        err = true;
+        goto out;
+    } // delta angles
+
+    if (!isfinite(correctedDelAng.x) || !isfinite(correctedDelAng.y) || !isfinite(correctedDelAng.z)) {
+        err_report->statesNaN = true;
+        ekf_debug("correctedDelAng NaN: x: %f y: %f z: %f", (double)correctedDelAng.x, (double)correctedDelAng.y, (double)correctedDelAng.z);
+        err = true;
+        goto out;
+    } // delta angles
+
+    if (!isfinite(summedDelVel.x) || !isfinite(summedDelVel.y) || !isfinite(summedDelVel.z)) {
+        err_report->statesNaN = true;
+        ekf_debug("summedDelVel NaN: x: %f y: %f z: %f", (double)summedDelVel.x, (double)summedDelVel.y, (double)summedDelVel.z);
+        err = true;
+        goto out;
+    } // delta velocities
+
+    // check all states and covariance matrices
+    for (unsigned i = 0; i < n_states; i++) {
+        for (unsigned j = 0; j < n_states; j++) {
+            if (!isfinite(KH[i][j])) {
+
+                err_report->covarianceNaN = true;
+                err = true;
+                ekf_debug("KH NaN");
+                goto out;
+            } //  intermediate result used for covariance updates
+
+            if (!isfinite(KHP[i][j])) {
+
+                err_report->covarianceNaN = true;
+                err = true;
+                ekf_debug("KHP NaN");
+                goto out;
+            } // intermediate result used for covariance updates
+
+            if (!isfinite(P[i][j])) {
+
+                err_report->covarianceNaN = true;
+                err = true;
+                ekf_debug("P NaN");
+            } // covariance matrix
+        }
+
+        if (!isfinite(Kfusion[i])) {
+
+            err_report->kalmanGainsNaN = true;
+            ekf_debug("Kfusion NaN");
+            err = true;
+            goto out;
+        } // Kalman gains
+
+        if (!isfinite(states[i])) {
+
+            err_report->statesNaN = true;
+            ekf_debug("states NaN: i: %u val: %f", i, states[i]);
+            err = true;
+            goto out;
+        } // state matrix
+    }
+
+out:
+    if (err) {
+        FillErrorReport(err_report);
+    }
+
+    return err;
+
+}
+
+/**
+ * Check the filter inputs and bound its operational state
+ *
+ * This check will reset the filter states if required
+ * due to a failure of consistency or timeout checks.
+ * it should be run after the measurement data has been
+ * updated, but before any of the fusion steps are
+ * executed.
+ */
+int AttPosEKF::CheckAndBound()
+{
+
+    // Store the old filter state
+    bool currStaticMode = staticMode;
+
+    // Reset the filter if the states went NaN
+    if (StatesNaN(&last_ekf_error)) {
+        ekf_debug("re-initializing dynamic");
+
+        InitializeDynamic(velNED);
+
+        return 1;
+    }
+
+    // Reset the filter if the IMU data is too old
+    if (dtIMU > 0.2f) {
+
+        ResetVelocity();
+        ResetPosition();
+        ResetHeight();
+        ResetStoredStates();
+
+        // that's all we can do here, return
+        return 2;
+    }
+
+    // Check if we're on ground - this also sets static mode.
+    OnGroundCheck();
+
+    // Check if we switched between states
+    if (currStaticMode != staticMode) {
+        ResetVelocity();
+        ResetPosition();
+        ResetHeight();
+        ResetStoredStates();
+
+        return 3;
+    }
+
+    return 0;
+}
+
+void AttPosEKF::AttitudeInit(float ax, float ay, float az, float mx, float my, float mz, float *initQuat)
+{
+    float initialRoll, initialPitch;
+    float cosRoll, sinRoll, cosPitch, sinPitch;
+    float magX, magY;
+    float initialHdg, cosHeading, sinHeading;
+
+    initialRoll = atan2f(-ay, -az);
+    initialPitch = atan2f(ax, -az);
+
+    cosRoll = cosf(initialRoll);
+    sinRoll = sinf(initialRoll);
+    cosPitch = cosf(initialPitch);
+    sinPitch = sinf(initialPitch);
+
+    magX = mx * cosPitch + my * sinRoll * sinPitch + mz * cosRoll * sinPitch;
+
+    magY = my * cosRoll - mz * sinRoll;
+
+    initialHdg = atan2f(-magY, magX);
+
+    cosRoll = cosf(initialRoll * 0.5f);
+    sinRoll = sinf(initialRoll * 0.5f);
+
+    cosPitch = cosf(initialPitch * 0.5f);
+    sinPitch = sinf(initialPitch * 0.5f);
+
+    cosHeading = cosf(initialHdg * 0.5f);
+    sinHeading = sinf(initialHdg * 0.5f);
+
+    initQuat[0] = cosRoll * cosPitch * cosHeading + sinRoll * sinPitch * sinHeading;
+    initQuat[1] = sinRoll * cosPitch * cosHeading - cosRoll * sinPitch * sinHeading;
+    initQuat[2] = cosRoll * sinPitch * cosHeading + sinRoll * cosPitch * sinHeading;
+    initQuat[3] = cosRoll * cosPitch * sinHeading - sinRoll * sinPitch * cosHeading;
+}
+
+void AttPosEKF::InitializeDynamic(float (&initvelNED)[3])
+{
+
+    // Clear the init flag
+    statesInitialised = false;
+
+    ZeroVariables();
+
+    // Calculate initial filter quaternion states from raw measurements
+    float initQuat[4];
+    Vector3f initMagXYZ;
+    initMagXYZ   = magData - magBias;
+    AttitudeInit(accel.x, accel.y, accel.z, initMagXYZ.x, initMagXYZ.y, initMagXYZ.z, initQuat);
+
+    // Calculate initial Tbn matrix and rotate Mag measurements into NED
+    // to set initial NED magnetic field states
+    Mat3f DCM;
+    quat2Tbn(DCM, initQuat);
+    Vector3f initMagNED;
+    initMagXYZ   = magData - magBias;
+    initMagNED.x = DCM.x.x*initMagXYZ.x + DCM.x.y*initMagXYZ.y + DCM.x.z*initMagXYZ.z;
+    initMagNED.y = DCM.y.x*initMagXYZ.x + DCM.y.y*initMagXYZ.y + DCM.y.z*initMagXYZ.z;
+    initMagNED.z = DCM.z.x*initMagXYZ.x + DCM.z.y*initMagXYZ.y + DCM.z.z*initMagXYZ.z;
+
+    magstate.q0 = initQuat[0];
+    magstate.q1 = initQuat[1];
+    magstate.q2 = initQuat[2];
+    magstate.q3 = initQuat[3];
+    magstate.magN = magData.x;
+    magstate.magE = magData.y;
+    magstate.magD = magData.z;
+    magstate.magXbias = magBias.x;
+    magstate.magYbias = magBias.y;
+    magstate.magZbias = magBias.z;
+    magstate.R_MAG = sq(magMeasurementSigma);
+    magstate.DCM = DCM;
+
+    // write to state vector
+    for (uint8_t j=0; j<=3; j++) states[j] = initQuat[j]; // quaternions
+    for (uint8_t j=4; j<=6; j++) states[j] = initvelNED[j-4]; // velocities
+    for (uint8_t j=7; j<=15; j++) states[j] = 0.0f; // positions, dAngBias, dVelBias, windVel
+    states[16] = initMagNED.x; // Magnetic Field North
+    states[17] = initMagNED.y; // Magnetic Field East
+    states[18] = initMagNED.z; // Magnetic Field Down
+    states[19] = magBias.x; // Magnetic Field Bias X
+    states[20] = magBias.y; // Magnetic Field Bias Y
+    states[21] = magBias.z; // Magnetic Field Bias Z
+    states[22] = 0.0f; // terrain height
+
+    ResetVelocity();
+    ResetPosition();
+    ResetHeight();
+
+    statesInitialised = true;
+
+    // initialise the covariance matrix
+    CovarianceInit();
+
+    //Define Earth rotation vector in the NED navigation frame
+    calcEarthRateNED(earthRateNED, latRef);
+
+    //Initialise summed variables used by covariance prediction
+    summedDelAng.x = 0.0f;
+    summedDelAng.y = 0.0f;
+    summedDelAng.z = 0.0f;
+    summedDelVel.x = 0.0f;
+    summedDelVel.y = 0.0f;
+    summedDelVel.z = 0.0f;
+}
+
+void AttPosEKF::InitialiseFilter(float (&initvelNED)[3], double referenceLat, double referenceLon, float referenceHgt)
+{
+    //store initial lat,long and height
+    latRef = referenceLat;
+    lonRef = referenceLon;
+    hgtRef = referenceHgt;
+    refSet = true;
+
+    memset(&last_ekf_error, 0, sizeof(last_ekf_error));
+
+    InitializeDynamic(initvelNED);
+}
+
+void AttPosEKF::ZeroVariables()
+{
+    // Do the data structure init
+    for (unsigned i = 0; i < n_states; i++) {
+        for (unsigned j = 0; j < n_states; j++) {
+            KH[i][j] = 0.0f; //  intermediate result used for covariance updates
+            KHP[i][j] = 0.0f; // intermediate result used for covariance updates
+            P[i][j] = 0.0f; // covariance matrix
+        }
+
+        Kfusion[i] = 0.0f; // Kalman gains
+        states[i] = 0.0f; // state matrix
+    }
+
+    correctedDelAng.zero();
+    summedDelAng.zero();
+    summedDelVel.zero();
+
+    for (unsigned i = 0; i < data_buffer_size; i++) {
+
+        for (unsigned j = 0; j < n_states; j++) {
+            storedStates[j][i] = 0.0f;
+        }
+
+        statetimeStamp[i] = 0;
+    }
+
+    memset(&magstate, 0, sizeof(magstate));
+    magstate.q0 = 1.0f;
+    magstate.DCM.identity();
+
+    memset(&current_ekf_state, 0, sizeof(current_ekf_state));
+
+}
+
+void AttPosEKF::GetFilterState(struct ekf_status_report *state)
+{
+    memcpy(state, &current_ekf_state, sizeof(*state));
+}
+
+void AttPosEKF::GetLastErrorState(struct ekf_status_report *last_error)
+{
+    memcpy(last_error, &last_ekf_error, sizeof(*last_error));
+}
diff --git a/src/modules/fw_att_pos_estimator/estimator.h b/src/modules/ekf_att_pos_estimator/estimator.h
index e62f1a98a..e118ae573 100644
--- a/src/modules/fw_att_pos_estimator/estimator.h
+++ b/src/modules/ekf_att_pos_estimator/estimator.h
@@ -20,7 +20,7 @@ public:
     float z;
 
     float length(void) const;
-    Vector3f zero(void) const;
+    void zero(void);
 };
 
 class Mat3f
@@ -33,6 +33,7 @@ public:
 
     Mat3f();
 
+    void identity();
     Mat3f transpose(void) const;
 };
 
@@ -45,14 +46,9 @@ Vector3f operator*(Vector3f vecIn1, float sclIn1);
 
 void swap_var(float &d1, float &d2);
 
-const unsigned int n_states = 21;
+const unsigned int n_states = 23;
 const unsigned int data_buffer_size = 50;
 
-const float covTimeStepMax = 0.07f; // maximum time allowed between covariance predictions
-const float covDelAngMax = 0.02f; // maximum delta angle between covariance predictions
-
-// extern bool staticMode;
-
 enum GPS_FIX {
     GPS_FIX_NOFIX = 0,
     GPS_FIX_2D = 2,
@@ -82,6 +78,88 @@ public:
     AttPosEKF();
     ~AttPosEKF();
 
+
+
+    /* ##############################################
+     *
+     *   M A I N    F I L T E R    P A R A M E T E R S
+     *
+     * ########################################### */
+
+    /*
+     * parameters are defined here and initialised in
+     * the InitialiseParameters() (which is just 20 lines down)
+     */
+
+    float covTimeStepMax; // maximum time allowed between covariance predictions
+    float covDelAngMax; // maximum delta angle between covariance predictions
+    float rngFinderPitch; // pitch angle of laser range finder in radians. Zero is aligned with the Z body axis. Positive is RH rotation about Y body axis.
+
+    float yawVarScale;
+    float windVelSigma;
+    float dAngBiasSigma;
+    float dVelBiasSigma;
+    float magEarthSigma;
+    float magBodySigma;
+    float gndHgtSigma;
+
+    float vneSigma;
+    float vdSigma;
+    float posNeSigma;
+    float posDSigma;
+    float magMeasurementSigma;
+    float airspeedMeasurementSigma;
+
+    float gyroProcessNoise;
+    float accelProcessNoise;
+
+    float EAS2TAS; // ratio f true to equivalent airspeed
+
+    void InitialiseParameters()
+    {
+        covTimeStepMax = 0.07f; // maximum time allowed between covariance predictions
+        covDelAngMax = 0.02f; // maximum delta angle between covariance predictions
+        rngFinderPitch = 0.0f; // pitch angle of laser range finder in radians. Zero is aligned with the Z body axis. Positive is RH rotation about Y body axis.
+        EAS2TAS = 1.0f;
+
+        yawVarScale = 1.0f;
+        windVelSigma = 0.1f;
+        dAngBiasSigma = 5.0e-7f;
+        dVelBiasSigma = 1e-4f;
+        magEarthSigma = 3.0e-4f;
+        magBodySigma  = 3.0e-4f;
+        gndHgtSigma  = 0.02f; // assume 2% terrain gradient 1-sigma
+
+        vneSigma = 0.2f;
+        vdSigma = 0.3f;
+        posNeSigma = 2.0f;
+        posDSigma = 2.0f;
+
+        magMeasurementSigma = 0.05;
+        airspeedMeasurementSigma = 1.4f;
+        gyroProcessNoise = 1.4544411e-2f;
+        accelProcessNoise = 0.5f;
+    }
+
+    struct {
+        unsigned obsIndex;
+        float MagPred[3];
+        float SH_MAG[9];
+        float q0;
+        float q1;
+        float q2;
+        float q3;
+        float magN;
+        float magE;
+        float magD;
+        float magXbias;
+        float magYbias;
+        float magZbias;
+        float R_MAG;
+        Mat3f DCM;
+    } magstate;
+
+
     // Global variables
     float KH[n_states][n_states]; //  intermediate result used for covariance updates
     float KHP[n_states][n_states]; // intermediate result used for covariance updates
@@ -96,6 +174,7 @@ public:
     float statesAtHgtTime[n_states]; // States at the effective measurement time for the hgtMea measurement
     float statesAtMagMeasTime[n_states]; // filter satates at the effective measurement time
     float statesAtVtasMeasTime[n_states]; // filter states at the effective measurement time
+    float statesAtRngTime[n_states]; // filter states at the effective measurement time
 
     Vector3f correctedDelAng; // delta angles about the xyz body axes corrected for errors (rad)
     Vector3f correctedDelVel; // delta velocities along the XYZ body axes corrected for errors (m/s)
@@ -104,6 +183,10 @@ public:
     float accNavMag; // magnitude of navigation accel (- used to adjust GPS obs variance (m/s^2)
     Vector3f earthRateNED; // earths angular rate vector in NED (rad/s)
     Vector3f angRate; // angular rate vector in XYZ body axes measured by the IMU (rad/s)
+
+    Mat3f Tbn; // transformation matrix from body to NED coordinates
+    Mat3f Tnb; // transformation amtrix from NED to body coordinates
+
     Vector3f accel; // acceleration vector in XYZ body axes measured by the IMU (m/s^2)
     Vector3f dVelIMU;
     Vector3f dAngIMU;
@@ -115,26 +198,28 @@ public:
     float velNED[3]; // North, East, Down velocity obs (m/s)
     float posNE[2]; // North, East position obs (m)
     float hgtMea; //  measured height (m)
+    float rngMea; // Ground distance
     float posNED[3]; // North, East Down position (m)
 
     float innovMag[3]; // innovation output
     float varInnovMag[3]; // innovation variance output
     Vector3f magData; // magnetometer flux radings in X,Y,Z body axes
     float innovVtas; // innovation output
+    float innovRng; ///< Range finder innovation
     float varInnovVtas; // innovation variance output
     float VtasMeas; // true airspeed measurement (m/s)
-    float latRef; // WGS-84 latitude of reference point (rad)
-    float lonRef; // WGS-84 longitude of reference point (rad)
+    double latRef; // WGS-84 latitude of reference point (rad)
+    double lonRef; // WGS-84 longitude of reference point (rad)
     float hgtRef; // WGS-84 height of reference point (m)
+    bool refSet;                ///< flag to indicate if the reference position has been set
     Vector3f magBias; // states representing magnetometer bias vector in XYZ body axes
-    uint8_t covSkipCount; // Number of state prediction frames (IMU daya updates to skip before doing the covariance prediction
-    float EAS2TAS; // ratio f true to equivalent airspeed
+    unsigned covSkipCount; // Number of state prediction frames (IMU daya updates to skip before doing the covariance prediction
 
     // GPS input data variables
     float gpsCourse;
     float gpsVelD;
-    float gpsLat;
-    float gpsLon;
+    double gpsLat;
+    double gpsLon;
     float gpsHgt;
     uint8_t GPSstatus;
 
@@ -148,11 +233,13 @@ public:
     bool fuseHgtData; // this boolean causes the hgtMea obs to be fused
     bool fuseMagData; // boolean true when magnetometer data is to be fused
     bool fuseVtasData; // boolean true when airspeed data is to be fused
+    bool fuseRngData;   ///< true when range data is fused
 
     bool onGround;    ///< boolean true when the flight vehicle is on the ground (not flying)
     bool staticMode;    ///< boolean true if no position feedback is fused
     bool useAirspeed;    ///< boolean true if airspeed data is being used
     bool useCompass;    ///< boolean true if magnetometer data is being used
+    bool useRangeFinder;     ///< true when rangefinder is being used
 
     struct ekf_status_report current_ekf_state;
     struct ekf_status_report last_ekf_error;
@@ -172,6 +259,10 @@ void FuseMagnetometer();
 
 void FuseAirspeed();
 
+void FuseRangeFinder();
+
+void FuseOpticalFlow();
+
 void zeroRows(float (&covMat)[n_states][n_states], uint8_t first, uint8_t last);
 
 void zeroCols(float (&covMat)[n_states][n_states], uint8_t first, uint8_t last);
@@ -192,7 +283,7 @@ void StoreStates(uint64_t timestamp_ms);
  *         time-wise where valid states were updated and invalid remained at the old
  *         value.
  */
-int RecallStates(float statesForFusion[n_states], uint64_t msec);
+int RecallStates(float *statesForFusion, uint64_t msec);
 
 void ResetStoredStates();
 
@@ -206,7 +297,7 @@ static void quat2eul(float (&eul)[3], const float (&quat)[4]);
 
 static void calcvelNED(float (&velNED)[3], float gpsCourse, float gpsGndSpd, float gpsVelD);
 
-static void calcposNED(float (&posNED)[3], float lat, float lon, float hgt, float latRef, float lonRef, float hgtRef);
+static void calcposNED(float (&posNED)[3], double lat, double lon, float hgt, double latRef, double lonRef, float hgtRef);
 
 static void calcLLH(float (&posNED)[3], float lat, float lon, float hgt, float latRef, float lonRef, float hgtRef);
 
@@ -218,7 +309,7 @@ void OnGroundCheck();
 
 void CovarianceInit();
 
-void InitialiseFilter(float (&initvelNED)[3]);
+void InitialiseFilter(float (&initvelNED)[3], double referenceLat, double referenceLon, float referenceHgt);
 
 float ConstrainFloat(float val, float min, float max);
 
diff --git a/src/modules/fw_att_pos_estimator/fw_att_pos_estimator_main.cpp b/src/modules/ekf_att_pos_estimator/fw_att_pos_estimator_main.cpp
index 3d94feb20..e5435e843 100644
--- a/src/modules/fw_att_pos_estimator/fw_att_pos_estimator_main.cpp
+++ b/src/modules/ekf_att_pos_estimator/fw_att_pos_estimator_main.cpp
@@ -73,6 +73,7 @@
 #include <uORB/topics/parameter_update.h>
 #include <uORB/topics/estimator_status.h>
 #include <uORB/topics/actuator_armed.h>
+#include <uORB/topics/home_position.h>
 #include <systemlib/param/param.h>
 #include <systemlib/err.h>
 #include <geo/geo.h>
@@ -90,7 +91,7 @@
  *
  * @ingroup apps
  */
-extern "C" __EXPORT int fw_att_pos_estimator_main(int argc, char *argv[]);
+extern "C" __EXPORT int ekf_att_pos_estimator_main(int argc, char *argv[]);
 
 __EXPORT uint32_t millis();
 
@@ -102,8 +103,6 @@ uint32_t millis()
 	return IMUmsec;
 }
 
-static void print_status();
-
 class FixedwingEstimator
 {
 public:
@@ -152,6 +151,7 @@ private:
 	int 		_params_sub;			/**< notification of parameter updates */
 	int 		_manual_control_sub;		/**< notification of manual control updates */
 	int		_mission_sub;
+	int		_home_sub;			/**< home position as defined by commander / user */
 
 	orb_advert_t	_att_pub;			/**< vehicle attitude */
 	orb_advert_t	_global_pos_pub;		/**< global position */
@@ -177,6 +177,8 @@ private:
 	struct sensor_combined_s			_sensor_combined;
 #endif
 
+	struct map_projection_reference_s	_pos_ref;
+
 	float						_baro_ref;		/**< barometer reference altitude */
 	float						_baro_gps_offset;	/**< offset between GPS and baro */
 
@@ -190,6 +192,7 @@ private:
 
 	bool						_initialized;
 	bool						_gps_initialized;
+	uint64_t					_gps_start_time;
 
 	int						_mavlink_fd;
 
@@ -199,6 +202,18 @@ private:
 		int32_t	height_delay_ms;
 		int32_t	mag_delay_ms;
 		int32_t	tas_delay_ms;
+		float velne_noise;
+		float veld_noise;
+		float posne_noise;
+		float posd_noise;
+		float mag_noise;
+		float gyro_pnoise;
+		float acc_pnoise;
+		float gbias_pnoise;
+		float abias_pnoise;
+		float mage_pnoise;
+		float magb_pnoise;
+		float eas_noise;
 	}		_parameters;			/**< local copies of interesting parameters */
 
 	struct {
@@ -207,6 +222,18 @@ private:
 		param_t	height_delay_ms;
 		param_t	mag_delay_ms;
 		param_t	tas_delay_ms;
+		param_t velne_noise;
+		param_t veld_noise;
+		param_t posne_noise;
+		param_t posd_noise;
+		param_t mag_noise;
+		param_t gyro_pnoise;
+		param_t acc_pnoise;
+		param_t gbias_pnoise;
+		param_t abias_pnoise;
+		param_t mage_pnoise;
+		param_t magb_pnoise;
+		param_t eas_noise;
 	}		_parameter_handles;		/**< handles for interesting parameters */
 
 	AttPosEKF					*_ekf;
@@ -279,6 +306,25 @@ FixedwingEstimator::FixedwingEstimator() :
 	_local_pos_pub(-1),
 	_estimator_status_pub(-1),
 
+	_att({}),
+	_gyro({}),
+	_accel({}),
+	_mag({}),
+	_airspeed({}),
+	_baro({}),
+	_vstatus({}),
+	_global_pos({}),
+	_local_pos({}),
+	_gps({}),
+
+	_gyro_offsets({}),
+	_accel_offsets({}),
+	_mag_offsets({}),
+
+	#ifdef SENSOR_COMBINED_SUB
+	_sensor_combined({}),
+	#endif
+
 	_baro_ref(0.0f),
 	_baro_gps_offset(0.0f),
 
@@ -300,13 +346,25 @@ FixedwingEstimator::FixedwingEstimator() :
 	_velocity_z_filtered(0.0f)
 {
 
-	_mavlink_fd = open(MAVLINK_LOG_DEVICE, 0);
+	last_run = hrt_absolute_time();
 
 	_parameter_handles.vel_delay_ms = param_find("PE_VEL_DELAY_MS");
 	_parameter_handles.pos_delay_ms = param_find("PE_POS_DELAY_MS");
 	_parameter_handles.height_delay_ms = param_find("PE_HGT_DELAY_MS");
 	_parameter_handles.mag_delay_ms = param_find("PE_MAG_DELAY_MS");
 	_parameter_handles.tas_delay_ms = param_find("PE_TAS_DELAY_MS");
+	_parameter_handles.velne_noise = param_find("PE_VELNE_NOISE");
+	_parameter_handles.veld_noise = param_find("PE_VELD_NOISE");
+	_parameter_handles.posne_noise = param_find("PE_POSNE_NOISE");
+	_parameter_handles.posd_noise = param_find("PE_POSD_NOISE");
+	_parameter_handles.mag_noise = param_find("PE_MAG_NOISE");
+	_parameter_handles.gyro_pnoise = param_find("PE_GYRO_PNOISE");
+	_parameter_handles.acc_pnoise = param_find("PE_ACC_PNOISE");
+	_parameter_handles.gbias_pnoise = param_find("PE_GBIAS_PNOISE");
+	_parameter_handles.abias_pnoise = param_find("PE_ABIAS_PNOISE");
+	_parameter_handles.mage_pnoise = param_find("PE_MAGE_PNOISE");
+	_parameter_handles.magb_pnoise = param_find("PE_MAGB_PNOISE");
+	_parameter_handles.eas_noise = param_find("PE_EAS_NOISE");
 
 	/* fetch initial parameter values */
 	parameters_update();
@@ -320,6 +378,10 @@ FixedwingEstimator::FixedwingEstimator() :
 	if (fd > 0) {
 		res = ioctl(fd, GYROIOCGSCALE, (long unsigned int)&_gyro_offsets);
 		close(fd);
+
+		if (res) {
+			warnx("G SCALE FAIL");
+		}
 	}
 
 	fd = open(ACCEL_DEVICE_PATH, O_RDONLY);
@@ -327,6 +389,10 @@ FixedwingEstimator::FixedwingEstimator() :
 	if (fd > 0) {
 		res = ioctl(fd, ACCELIOCGSCALE, (long unsigned int)&_accel_offsets);
 		close(fd);
+
+		if (res) {
+			warnx("A SCALE FAIL");
+		}
 	}
 
 	fd = open(MAG_DEVICE_PATH, O_RDONLY);
@@ -334,6 +400,10 @@ FixedwingEstimator::FixedwingEstimator() :
 	if (fd > 0) {
 		res = ioctl(fd, MAGIOCGSCALE, (long unsigned int)&_mag_offsets);
 		close(fd);
+
+		if (res) {
+			warnx("M SCALE FAIL");
+		}
 	}
 }
 
@@ -371,6 +441,36 @@ FixedwingEstimator::parameters_update()
 	param_get(_parameter_handles.height_delay_ms, &(_parameters.height_delay_ms));
 	param_get(_parameter_handles.mag_delay_ms, &(_parameters.mag_delay_ms));
 	param_get(_parameter_handles.tas_delay_ms, &(_parameters.tas_delay_ms));
+	param_get(_parameter_handles.velne_noise, &(_parameters.velne_noise));
+	param_get(_parameter_handles.veld_noise, &(_parameters.veld_noise));
+	param_get(_parameter_handles.posne_noise, &(_parameters.posne_noise));
+	param_get(_parameter_handles.posd_noise, &(_parameters.posd_noise));
+	param_get(_parameter_handles.mag_noise, &(_parameters.mag_noise));
+	param_get(_parameter_handles.gyro_pnoise, &(_parameters.gyro_pnoise));
+	param_get(_parameter_handles.acc_pnoise, &(_parameters.acc_pnoise));
+	param_get(_parameter_handles.gbias_pnoise, &(_parameters.gbias_pnoise));
+	param_get(_parameter_handles.abias_pnoise, &(_parameters.abias_pnoise));
+	param_get(_parameter_handles.mage_pnoise, &(_parameters.mage_pnoise));
+	param_get(_parameter_handles.magb_pnoise, &(_parameters.magb_pnoise));
+	param_get(_parameter_handles.eas_noise, &(_parameters.eas_noise));
+
+	if (_ekf) {
+		// _ekf->yawVarScale = 1.0f;
+		// _ekf->windVelSigma = 0.1f;
+		_ekf->dAngBiasSigma = _parameters.gbias_pnoise;
+		_ekf->dVelBiasSigma = _parameters.abias_pnoise;
+		_ekf->magEarthSigma = _parameters.mage_pnoise;
+		_ekf->magBodySigma  = _parameters.magb_pnoise;
+		// _ekf->gndHgtSigma  = 0.02f;
+		_ekf->vneSigma = _parameters.velne_noise;
+		_ekf->vdSigma = _parameters.veld_noise;
+		_ekf->posNeSigma = _parameters.posne_noise;
+		_ekf->posDSigma = _parameters.posd_noise;
+		_ekf->magMeasurementSigma = _parameters.mag_noise;
+		_ekf->gyroProcessNoise = _parameters.gyro_pnoise;
+        	_ekf->accelProcessNoise = _parameters.acc_pnoise;
+		_ekf->airspeedMeasurementSigma = _parameters.eas_noise;
+	}
 
 	return OK;
 }
@@ -400,6 +500,7 @@ float dt = 0.0f; // time lapsed since last covariance prediction
 void
 FixedwingEstimator::task_main()
 {
+	_mavlink_fd = open(MAVLINK_LOG_DEVICE, 0);
 
 	_ekf = new AttPosEKF();
 
@@ -415,6 +516,7 @@ FixedwingEstimator::task_main()
 	_gps_sub = orb_subscribe(ORB_ID(vehicle_gps_position));
 	_vstatus_sub = orb_subscribe(ORB_ID(vehicle_status));
 	_params_sub = orb_subscribe(ORB_ID(parameter_update));
+	_home_sub = orb_subscribe(ORB_ID(home_position));
 
 	/* rate limit vehicle status updates to 5Hz */
 	orb_set_interval(_vstatus_sub, 200);
@@ -434,6 +536,7 @@ FixedwingEstimator::task_main()
 	orb_set_interval(_sensor_combined_sub, 4);
 #endif
 
+	/* sets also parameters in the EKF object */
 	parameters_update();
 
 	/* set initial filter state */
@@ -469,12 +572,19 @@ FixedwingEstimator::task_main()
 	fds[1].events = POLLIN;
 #endif
 
-	hrt_abstime start_time = hrt_absolute_time();
-
 	bool newDataGps = false;
 	bool newAdsData = false;
 	bool newDataMag = false;
 
+	// Reset relevant structs
+	_gps = {};
+
+	#ifndef SENSOR_COMBINED_SUB
+	_gyro = {};
+	#else
+	_sensor_combined = {};
+	#endif
+
 	while (!_task_should_exit) {
 
 		/* wait for up to 500ms for data */
@@ -538,21 +648,28 @@ FixedwingEstimator::task_main()
 			last_run = _gyro.timestamp;
 
 			/* guard against too large deltaT's */
-			if (deltaT > 1.0f)
+			if (!isfinite(deltaT) || deltaT > 1.0f || deltaT < 0.000001f) {
 				deltaT = 0.01f;
+			}
 
 
 			// Always store data, independent of init status
 			/* fill in last data set */
 			_ekf->dtIMU = deltaT;
 
-			_ekf->angRate.x = _gyro.x;
-			_ekf->angRate.y = _gyro.y;
-			_ekf->angRate.z = _gyro.z;
+			if (isfinite(_gyro.x) &&
+				isfinite(_gyro.y) &&
+				isfinite(_gyro.z)) {
+				_ekf->angRate.x = _gyro.x;
+				_ekf->angRate.y = _gyro.y;
+				_ekf->angRate.z = _gyro.z;
+			}
 
-			_ekf->accel.x = _accel.x;
-			_ekf->accel.y = _accel.y;
-			_ekf->accel.z = _accel.z;
+			if (accel_updated) {
+				_ekf->accel.x = _accel.x;
+				_ekf->accel.y = _accel.y;
+				_ekf->accel.z = _accel.z;
+			}
 
 			_ekf->dAngIMU = 0.5f * (angRate + lastAngRate) * dtIMU;
 			_ekf->lastAngRate = angRate;
@@ -578,23 +695,31 @@ FixedwingEstimator::task_main()
 			IMUmsec = _sensor_combined.timestamp / 1e3f;
 
 			float deltaT = (_sensor_combined.timestamp - last_run) / 1e6f;
-			last_run = _sensor_combined.timestamp;
 
 			/* guard against too large deltaT's */
-			if (deltaT > 1.0f || deltaT < 0.000001f)
+			if (!isfinite(deltaT) || deltaT > 1.0f || deltaT < 0.000001f) {
 				deltaT = 0.01f;
+			}
+
+			last_run = _sensor_combined.timestamp;
 
 			// Always store data, independent of init status
 			/* fill in last data set */
 			_ekf->dtIMU = deltaT;
 
-			_ekf->angRate.x = _sensor_combined.gyro_rad_s[0];
-			_ekf->angRate.y = _sensor_combined.gyro_rad_s[1];
-			_ekf->angRate.z = _sensor_combined.gyro_rad_s[2];
+			if (isfinite(_sensor_combined.gyro_rad_s[0]) &&
+				isfinite(_sensor_combined.gyro_rad_s[1]) &&
+				isfinite(_sensor_combined.gyro_rad_s[2])) {
+				_ekf->angRate.x = _sensor_combined.gyro_rad_s[0];
+				_ekf->angRate.y = _sensor_combined.gyro_rad_s[1];
+				_ekf->angRate.z = _sensor_combined.gyro_rad_s[2];
+			}
 
-			_ekf->accel.x = _sensor_combined.accelerometer_m_s2[0];
-			_ekf->accel.y = _sensor_combined.accelerometer_m_s2[1];
-			_ekf->accel.z = _sensor_combined.accelerometer_m_s2[2];
+			if (accel_updated) {
+				_ekf->accel.x = _sensor_combined.accelerometer_m_s2[0];
+				_ekf->accel.y = _sensor_combined.accelerometer_m_s2[1];
+				_ekf->accel.z = _sensor_combined.accelerometer_m_s2[2];
+			}
 
 			_ekf->dAngIMU = 0.5f * (_ekf->angRate + lastAngRate) * _ekf->dtIMU;
 			lastAngRate = _ekf->angRate;
@@ -643,6 +768,9 @@ FixedwingEstimator::task_main()
 
 				} else {
 
+					/* store time of valid GPS measurement */
+					_gps_start_time = hrt_absolute_time();
+
 					/* check if we had a GPS outage for a long time */
 					if (hrt_elapsed_time(&last_gps) > 5 * 1000 * 1000) {
 						_ekf->ResetPosition();
@@ -663,6 +791,21 @@ FixedwingEstimator::task_main()
 					_ekf->gpsLat = math::radians(_gps.lat / (double)1e7);
 					_ekf->gpsLon = math::radians(_gps.lon / (double)1e7) - M_PI;
 					_ekf->gpsHgt = _gps.alt / 1e3f;
+
+					// if (_gps.s_variance_m_s > 0.25f && _gps.s_variance_m_s < 100.0f * 100.0f) {
+					// 	_ekf->vneSigma = sqrtf(_gps.s_variance_m_s);
+					// } else {
+					// 	_ekf->vneSigma = _parameters.velne_noise;
+					// }
+
+					// if (_gps.p_variance_m > 0.25f && _gps.p_variance_m < 100.0f * 100.0f) {
+					// 	_ekf->posNeSigma = sqrtf(_gps.p_variance_m);
+					// } else {
+					// 	_ekf->posNeSigma = _parameters.posne_noise;
+					// }
+
+					// warnx("vel: %8.4f pos: %8.4f", _gps.s_variance_m_s, _gps.p_variance_m);
+
 					newDataGps = true;
 
 				}
@@ -730,6 +873,8 @@ FixedwingEstimator::task_main()
 			 */
 			int check = _ekf->CheckAndBound();
 
+			const char* ekfname = "[ekf] ";
+
 			switch (check) {
 				case 0:
 					/* all ok */
@@ -738,26 +883,38 @@ FixedwingEstimator::task_main()
 				{
 					const char* str = "NaN in states, resetting";
 					warnx("%s", str);
-					mavlink_log_critical(_mavlink_fd, str);
+					mavlink_log_critical(_mavlink_fd, "%s%s", ekfname, str);
 					break;
 				}
 				case 2:
 				{
 					const char* str = "stale IMU data, resetting";
 					warnx("%s", str);
-					mavlink_log_critical(_mavlink_fd, str);
+					mavlink_log_critical(_mavlink_fd, "%s%s", ekfname, str);
 					break;
 				}
 				case 3:
 				{
-					const char* str = "switching dynamic / static state";
+					const char* str = "switching to dynamic state";
 					warnx("%s", str);
-					mavlink_log_critical(_mavlink_fd, str);
+					mavlink_log_critical(_mavlink_fd, "%s%s", ekfname, str);
 					break;
 				}
+
+				default:
+				{
+					const char* str = "unknown reset condition";
+					warnx("%s", str);
+					mavlink_log_critical(_mavlink_fd, "%s%s", ekfname, str);
+				}
 			}
 
-			// If non-zero, we got a problem
+			// XXX trap for testing
+			if (check == 1) {
+				errx(1, "NUMERIC ERROR IN FILTER");
+			}
+
+			// If non-zero, we got a filter reset
 			if (check) {
 
 				struct ekf_status_report ekf_report;
@@ -773,7 +930,7 @@ FixedwingEstimator::task_main()
 				rep.kalman_gain_nan = ekf_report.kalmanGainsNaN;
 
 				// Copy all states or at least all that we can fit
-				int i = 0;
+				unsigned i = 0;
 				unsigned ekf_n_states = (sizeof(ekf_report.states) / sizeof(ekf_report.states[0]));
 				unsigned max_states = (sizeof(rep.states) / sizeof(rep.states[0]));
 				rep.n_states = (ekf_n_states < max_states) ? ekf_n_states : max_states;
@@ -789,6 +946,7 @@ FixedwingEstimator::task_main()
 				} else {
 					_estimator_status_pub = orb_advertise(ORB_ID(estimator_status), &rep);
 				}
+
 			}
 
 
@@ -800,22 +958,28 @@ FixedwingEstimator::task_main()
 			// XXX we rather want to check all updated
 
 
-			if (hrt_elapsed_time(&start_time) > 100000) {
+			if (hrt_elapsed_time(&_gps_start_time) > 50000) {
 
-				if (!_gps_initialized && (_ekf->GPSstatus == 3)) {
+				// bool home_set;
+				// orb_check(_home_sub, &home_set);
+				// struct home_position_s home;
+				// orb_copy(ORB_ID(home_position), _home_sub, &home);
+
+				if (!_gps_initialized && _gps.fix_type > 2) {
 					_ekf->velNED[0] = _gps.vel_n_m_s;
 					_ekf->velNED[1] = _gps.vel_e_m_s;
 					_ekf->velNED[2] = _gps.vel_d_m_s;
 
-					double lat = _gps.lat * 1e-7;
-					double lon = _gps.lon * 1e-7;
-					float alt = _gps.alt * 1e-3;
+					// GPS is in scaled integers, convert
+					double lat = _gps.lat / 1.0e7;
+					double lon = _gps.lon / 1.0e7;
+					float alt = _gps.alt / 1e3f;
 
-					_ekf->InitialiseFilter(_ekf->velNED);
+					_ekf->InitialiseFilter(_ekf->velNED, math::radians(lat), math::radians(lon) - M_PI, alt);
 
 					// Initialize projection
 					_local_pos.ref_lat = _gps.lat;
-					_local_pos.ref_lon = _gps.lon;
+					_local_pos.ref_lon = _gps.alt;
 					_local_pos.ref_alt = alt;
 					_local_pos.ref_timestamp = _gps.timestamp_position;
 
@@ -825,9 +989,10 @@ FixedwingEstimator::task_main()
 					_ekf->baroHgt = _baro.altitude - _baro_ref;
 					_baro_gps_offset = _baro_ref - _local_pos.ref_alt;
 
-					// XXX this is not multithreading safe
-					map_projection_init(lat, lon);
-					mavlink_log_info(_mavlink_fd, "[position estimator] init ref: lat=%.7f, lon=%.7f, alt=%.2f", lat, lon, alt);
+					map_projection_init(&_pos_ref, lat, lon);
+					mavlink_log_info(_mavlink_fd, "[ekf] ref: LA %.4f,LO %.4f,ALT %.2f", lat, lon, (double)alt);
+					warnx("[ekf] HOME/REF: LA %8.4f,LO %8.4f,ALT %8.2f V: %8.4f %8.4f %8.4f", lat, lon, (double)alt,
+						(double)_ekf->velNED[0], (double)_ekf->velNED[1], (double)_ekf->velNED[2]);
 
 					_gps_initialized = true;
 
@@ -841,7 +1006,7 @@ FixedwingEstimator::task_main()
 
 					_ekf->posNE[0] = _ekf->posNED[0];
 					_ekf->posNE[1] = _ekf->posNED[1];
-					_ekf->InitialiseFilter(_ekf->velNED);
+					_ekf->InitialiseFilter(_ekf->velNED, 0.0, 0.0, 0.0f);
 				}
 			}
 
@@ -875,10 +1040,10 @@ FixedwingEstimator::task_main()
 
 				// perform a covariance prediction if the total delta angle has exceeded the limit
 				// or the time limit will be exceeded at the next IMU update
-				if ((dt >= (covTimeStepMax - _ekf->dtIMU)) || (_ekf->summedDelAng.length() > covDelAngMax)) {
+				if ((dt >= (_ekf->covTimeStepMax - _ekf->dtIMU)) || (_ekf->summedDelAng.length() > _ekf->covDelAngMax)) {
 					_ekf->CovariancePrediction(dt);
-					_ekf->summedDelAng = _ekf->summedDelAng.zero();
-					_ekf->summedDelVel = _ekf->summedDelVel.zero();
+					_ekf->summedDelAng.zero();
+					_ekf->summedDelVel.zero();
 					dt = 0.0f;
 				}
 
@@ -1062,18 +1227,16 @@ FixedwingEstimator::task_main()
 
 				_global_pos.timestamp = _local_pos.timestamp;
 
-				_global_pos.baro_valid = true;
-				_global_pos.global_valid = true;
-
 				if (_local_pos.xy_global) {
 					double est_lat, est_lon;
-					map_projection_reproject(_local_pos.x, _local_pos.y, &est_lat, &est_lon);
+					map_projection_reproject(&_pos_ref, _local_pos.x, _local_pos.y, &est_lat, &est_lon);
 					_global_pos.lat = est_lat;
 					_global_pos.lon = est_lon;
 					_global_pos.time_gps_usec = _gps.time_gps_usec;
+					_global_pos.eph = _gps.eph;
+					_global_pos.epv = _gps.epv;
 				}
 
-				/* set valid values even if position is not valid */
 				if (_local_pos.v_xy_valid) {
 					_global_pos.vel_n = _local_pos.vx;
 					_global_pos.vel_e = _local_pos.vy;
@@ -1084,10 +1247,7 @@ FixedwingEstimator::task_main()
 
 				/* local pos alt is negative, change sign and add alt offset */
 				_global_pos.alt = _local_pos.ref_alt + (-_local_pos.z);
-
-				if (_local_pos.z_valid) {
-					_global_pos.baro_alt = _local_pos.ref_alt - _baro_gps_offset - _local_pos.z;
-				}
+				_global_pos.rel_alt = (-_local_pos.z);
 
 				if (_local_pos.v_z_valid) {
 					_global_pos.vel_d = _local_pos.vz;
@@ -1095,6 +1255,9 @@ FixedwingEstimator::task_main()
 
 				_global_pos.yaw = _local_pos.yaw;
 
+				_global_pos.eph = _gps.eph_m;
+				_global_pos.epv = _gps.epv_m;
+
 				_global_pos.timestamp = _local_pos.timestamp;
 
 				/* lazily publish the global position only once available */
@@ -1125,7 +1288,7 @@ FixedwingEstimator::start()
 	ASSERT(_estimator_task == -1);
 
 	/* start the task */
-	_estimator_task = task_spawn_cmd("fw_att_pos_estimator",
+	_estimator_task = task_spawn_cmd("ekf_att_pos_estimator",
 					 SCHED_DEFAULT,
 					 SCHED_PRIORITY_MAX - 40,
 					 6000,
@@ -1159,7 +1322,7 @@ FixedwingEstimator::print_status()
 	// 15-17: Earth Magnetic Field Vector - gauss (North, East, Down)
 	// 18-20: Body Magnetic Field Vector - gauss (X,Y,Z)
 
-	printf("dtIMU: %8.6f dt: %8.6f IMUmsec: %d\n", _ekf->dtIMU, dt, (int)IMUmsec);
+	printf("dtIMU: %8.6f dt: %8.6f IMUmsec: %d\n", (double)_ekf->dtIMU, (double)dt, (int)IMUmsec);
 	printf("dvel: %8.6f %8.6f %8.6f accel: %8.6f %8.6f %8.6f\n", (double)_ekf->dVelIMU.x, (double)_ekf->dVelIMU.y, (double)_ekf->dVelIMU.z, (double)_ekf->accel.x, (double)_ekf->accel.y, (double)_ekf->accel.z);
 	printf("dang: %8.4f %8.4f %8.4f dang corr: %8.4f %8.4f %8.4f\n" , (double)_ekf->dAngIMU.x, (double)_ekf->dAngIMU.y, (double)_ekf->dAngIMU.z, (double)_ekf->correctedDelAng.x, (double)_ekf->correctedDelAng.y, (double)_ekf->correctedDelAng.z);
 	printf("states (quat)        [1-4]: %8.4f, %8.4f, %8.4f, %8.4f\n", (double)_ekf->states[0], (double)_ekf->states[1], (double)_ekf->states[2], (double)_ekf->states[3]);
@@ -1231,10 +1394,10 @@ int FixedwingEstimator::trip_nan() {
 	return ret;
 }
 
-int fw_att_pos_estimator_main(int argc, char *argv[])
+int ekf_att_pos_estimator_main(int argc, char *argv[])
 {
 	if (argc < 1)
-		errx(1, "usage: fw_att_pos_estimator {start|stop|status}");
+		errx(1, "usage: ekf_att_pos_estimator {start|stop|status}");
 
 	if (!strcmp(argv[1], "start")) {
 
diff --git a/src/modules/ekf_att_pos_estimator/fw_att_pos_estimator_params.c b/src/modules/ekf_att_pos_estimator/fw_att_pos_estimator_params.c
new file mode 100644
index 000000000..cfcd99858
--- /dev/null
+++ b/src/modules/ekf_att_pos_estimator/fw_att_pos_estimator_params.c
@@ -0,0 +1,260 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2013, 2014 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file fw_att_pos_estimator_params.c
+ *
+ * Parameters defined by the attitude and position estimator task
+ *
+ * @author Lorenz Meier <lm@inf.ethz.ch>
+ */
+
+#include <nuttx/config.h>
+
+#include <systemlib/param/param.h>
+
+/*
+ * Estimator parameters, accessible via MAVLink
+ *
+ */
+
+/**
+ * Velocity estimate delay
+ *
+ * The delay in milliseconds of the velocity estimate from GPS.
+ *
+ * @min 0
+ * @max 1000
+ * @group Position Estimator
+ */
+PARAM_DEFINE_INT32(PE_VEL_DELAY_MS, 230);
+
+/**
+ * Position estimate delay
+ *
+ * The delay in milliseconds of the position estimate from GPS.
+ *
+ * @min 0
+ * @max 1000
+ * @group Position Estimator
+ */
+PARAM_DEFINE_INT32(PE_POS_DELAY_MS, 210);
+
+/**
+ * Height estimate delay
+ *
+ * The delay in milliseconds of the height estimate from the barometer.
+ *
+ * @min 0
+ * @max 1000
+ * @group Position Estimator
+ */
+PARAM_DEFINE_INT32(PE_HGT_DELAY_MS, 350);
+
+/**
+ * Mag estimate delay
+ *
+ * The delay in milliseconds of the magnetic field estimate from
+ * the magnetometer.
+ *
+ * @min 0
+ * @max 1000
+ * @group Position Estimator
+ */
+PARAM_DEFINE_INT32(PE_MAG_DELAY_MS, 30);
+
+/**
+ * True airspeeed estimate delay
+ *
+ * The delay in milliseconds of the airspeed estimate.
+ *
+ * @min 0
+ * @max 1000
+ * @group Position Estimator
+ */
+PARAM_DEFINE_INT32(PE_TAS_DELAY_MS, 210);
+
+/**
+ * GPS vs. barometric altitude update weight
+ *
+ * RE-CHECK this.
+ *
+ * @min 0.0
+ * @max 1.0
+ * @group Position Estimator
+ */
+PARAM_DEFINE_FLOAT(PE_GPS_ALT_WGT, 0.9f);
+
+/**
+ * Airspeed measurement noise.
+ *
+ * Increasing this value will make the filter trust this sensor
+ * less and trust other sensors more.
+ *
+ * @min 0.5
+ * @max 5.0
+ * @group Position Estimator
+ */
+PARAM_DEFINE_FLOAT(PE_EAS_NOISE, 1.4f);
+
+/**
+ * Velocity measurement noise in north-east (horizontal) direction.
+ *
+ * Generic default: 0.3, multicopters: 0.5, ground vehicles: 0.5
+ *
+ * @min 0.05
+ * @max 5.0
+ * @group Position Estimator
+ */
+PARAM_DEFINE_FLOAT(PE_VELNE_NOISE, 0.3f);
+
+/**
+ * Velocity noise in down (vertical) direction
+ *
+ * Generic default: 0.5, multicopters: 0.7, ground vehicles: 0.7
+ *
+ * @min 0.05
+ * @max 5.0
+ * @group Position Estimator
+ */
+PARAM_DEFINE_FLOAT(PE_VELD_NOISE, 0.5f);
+
+/**
+ * Position noise in north-east (horizontal) direction
+ *
+ * Generic defaults: 0.5, multicopters: 0.5, ground vehicles: 0.5
+ *
+ * @min 0.1
+ * @max 10.0
+ * @group Position Estimator
+ */
+PARAM_DEFINE_FLOAT(PE_POSNE_NOISE, 0.5f);
+
+/**
+ * Position noise in down (vertical) direction
+ *
+ * Generic defaults: 0.5, multicopters: 1.0, ground vehicles: 1.0
+ *
+ * @min 0.1
+ * @max 10.0
+ * @group Position Estimator
+ */
+PARAM_DEFINE_FLOAT(PE_POSD_NOISE, 0.5f);
+
+/**
+ * Magnetometer measurement noise
+ *
+ * Generic defaults: 0.05, multicopters: 0.05, ground vehicles: 0.05
+ *
+ * @min 0.1
+ * @max 10.0
+ * @group Position Estimator
+ */
+PARAM_DEFINE_FLOAT(PE_MAG_NOISE, 0.05f);
+
+/**
+ * Gyro process noise
+ *
+ * Generic defaults: 0.015, multicopters: 0.015, ground vehicles: 0.015.
+ * This noise controls how much the filter trusts the gyro measurements.
+ * Increasing it makes the filter trust the gyro less and other sensors more.
+ *
+ * @min 0.001
+ * @max 0.05
+ * @group Position Estimator
+ */
+PARAM_DEFINE_FLOAT(PE_GYRO_PNOISE, 0.015f);
+
+/**
+ * Accelerometer process noise
+ *
+ * Generic defaults: 0.25, multicopters: 0.25, ground vehicles: 0.25.
+ * Increasing this value makes the filter trust the accelerometer less
+ * and other sensors more.
+ *
+ * @min 0.05
+ * @max 1.0
+ * @group Position Estimator
+ */
+PARAM_DEFINE_FLOAT(PE_ACC_PNOISE, 0.25f);
+
+/**
+ * Gyro bias estimate process noise
+ *
+ * Generic defaults: 1e-07f, multicopters: 1e-07f, ground vehicles: 1e-07f.
+ * Increasing this value will make the gyro bias converge faster but noisier.
+ *
+ * @min 0.0000001
+ * @max 0.00001
+ * @group Position Estimator
+ */
+PARAM_DEFINE_FLOAT(PE_GBIAS_PNOISE, 1e-07f);
+
+/**
+ * Accelerometer bias estimate process noise
+ *
+ * Generic defaults: 0.0001f, multicopters: 0.0001f, ground vehicles: 0.0001f.
+ * Increasing this value makes the bias estimation faster and noisier.
+ *
+ * @min 0.0001
+ * @max 0.001
+ * @group Position Estimator
+ */
+PARAM_DEFINE_FLOAT(PE_ABIAS_PNOISE, 0.0001f);
+
+/**
+ * Magnetometer earth frame offsets process noise
+ *
+ * Generic defaults: 0.0001, multicopters: 0.0001, ground vehicles: 0.0001.
+ * Increasing this value makes the magnetometer earth bias estimate converge
+ * faster but also noisier.
+ *
+ * @min 0.0001
+ * @max 0.01
+ * @group Position Estimator
+ */
+PARAM_DEFINE_FLOAT(PE_MAGE_PNOISE, 0.0003f);
+
+/**
+ * Magnetometer body frame offsets process noise
+ *
+ * Generic defaults: 0.0003, multicopters: 0.0003, ground vehicles: 0.0003.
+ * Increasing this value makes the magnetometer body bias estimate converge faster
+ * but also noisier.
+ *
+ * @min 0.0001
+ * @max 0.01
+ * @group Position Estimator
+ */
+PARAM_DEFINE_FLOAT(PE_MAGB_PNOISE, 0.0003f);
+
diff --git a/src/modules/fw_att_pos_estimator/module.mk b/src/modules/ekf_att_pos_estimator/module.mk
index c992959e0..30955d0dd 100644
--- a/src/modules/fw_att_pos_estimator/module.mk
+++ b/src/modules/ekf_att_pos_estimator/module.mk
@@ -35,7 +35,7 @@
 # Main Attitude and Position Estimator for Fixed Wing Aircraft
 #
 
-MODULE_COMMAND	= fw_att_pos_estimator
+MODULE_COMMAND	= ekf_att_pos_estimator
 
 SRCS		= fw_att_pos_estimator_main.cpp \
 		  fw_att_pos_estimator_params.c \
diff --git a/src/modules/fw_att_control/fw_att_control_main.cpp b/src/modules/fw_att_control/fw_att_control_main.cpp
index 5276b1c13..81bef0db3 100644
--- a/src/modules/fw_att_control/fw_att_control_main.cpp
+++ b/src/modules/fw_att_control/fw_att_control_main.cpp
@@ -782,7 +782,7 @@ FixedwingAttitudeControl::task_main()
 					_actuators.control[1] = (isfinite(pitch_u)) ? pitch_u + _parameters.trim_pitch : _parameters.trim_pitch;
 					if (!isfinite(pitch_u)) {
 						warnx("pitch_u %.4f, _yaw_ctrl.get_desired_rate() %.4f, airspeed %.4f, airspeed_scaling %.4f, roll_sp %.4f, pitch_sp %.4f, _roll_ctrl.get_desired_rate() %.4f, _pitch_ctrl.get_desired_rate() %.4f att_sp.roll_body %.4f",
-								pitch_u, _yaw_ctrl.get_desired_rate(), airspeed, airspeed_scaling, roll_sp, pitch_sp, _roll_ctrl.get_desired_rate(), _pitch_ctrl.get_desired_rate(), _att_sp.roll_body);
+								(double)pitch_u, (double)_yaw_ctrl.get_desired_rate(), (double)airspeed, (double)airspeed_scaling, (double)roll_sp, (double)pitch_sp, (double)_roll_ctrl.get_desired_rate(), (double)_pitch_ctrl.get_desired_rate(), (double)_att_sp.roll_body);
 					}
 
 					float yaw_u = _yaw_ctrl.control_bodyrate(_att.roll, _att.pitch,
@@ -791,16 +791,16 @@ FixedwingAttitudeControl::task_main()
 							_parameters.airspeed_min, _parameters.airspeed_max, airspeed, airspeed_scaling, lock_integrator);
 					_actuators.control[2] = (isfinite(yaw_u)) ? yaw_u + _parameters.trim_yaw : _parameters.trim_yaw;
 					if (!isfinite(yaw_u)) {
-						warnx("yaw_u %.4f", yaw_u);
+						warnx("yaw_u %.4f", (double)yaw_u);
 					}
 
 					/* throttle passed through */
 					_actuators.control[3] = (isfinite(throttle_sp)) ? throttle_sp : 0.0f;
 					if (!isfinite(throttle_sp)) {
-						warnx("throttle_sp %.4f", throttle_sp);
+						warnx("throttle_sp %.4f", (double)throttle_sp);
 					}
 				} else {
-					warnx("Non-finite setpoint roll_sp: %.4f, pitch_sp %.4f", roll_sp, pitch_sp);
+					warnx("Non-finite setpoint roll_sp: %.4f, pitch_sp %.4f", (double)roll_sp, (double)pitch_sp);
 				}
 
 				/*
diff --git a/src/modules/fw_att_pos_estimator/estimator.cpp b/src/modules/fw_att_pos_estimator/estimator.cpp
deleted file mode 100644
index c31217393..000000000
--- a/src/modules/fw_att_pos_estimator/estimator.cpp
+++ /dev/null
@@ -1,2248 +0,0 @@
-#include "estimator.h"
-
-#include <string.h>
-
-float Vector3f::length(void) const
-{
-    return sqrt(x*x + y*y + z*z);
-}
-
-Vector3f Vector3f::zero(void) const
-{
-    Vector3f ret = *this;
-    ret.x = 0.0;
-    ret.y = 0.0;
-    ret.z = 0.0;
-    return ret;
-}
-
-Mat3f::Mat3f() {
-    x.x = 1.0f;
-    x.y = 0.0f;
-    x.z = 0.0f;
-
-    y.x = 0.0f;
-    y.y = 1.0f;
-    y.z = 0.0f;
-
-    z.x = 0.0f;
-    z.y = 0.0f;
-    z.z = 1.0f;
-}
-
-Mat3f Mat3f::transpose(void) const
-{
-    Mat3f ret = *this;
-    swap_var(ret.x.y, ret.y.x);
-    swap_var(ret.x.z, ret.z.x);
-    swap_var(ret.y.z, ret.z.y);
-    return ret;
-}
-
-// overload + operator to provide a vector addition
-Vector3f operator+( Vector3f vecIn1, Vector3f vecIn2)
-{
-    Vector3f vecOut;
-    vecOut.x = vecIn1.x + vecIn2.x;
-    vecOut.y = vecIn1.y + vecIn2.y;
-    vecOut.z = vecIn1.z + vecIn2.z;
-    return vecOut;
-}
-
-// overload - operator to provide a vector subtraction
-Vector3f operator-( Vector3f vecIn1, Vector3f vecIn2)
-{
-    Vector3f vecOut;
-    vecOut.x = vecIn1.x - vecIn2.x;
-    vecOut.y = vecIn1.y - vecIn2.y;
-    vecOut.z = vecIn1.z - vecIn2.z;
-    return vecOut;
-}
-
-// overload * operator to provide a matrix vector product
-Vector3f operator*( Mat3f matIn, Vector3f vecIn)
-{
-    Vector3f vecOut;
-    vecOut.x = matIn.x.x*vecIn.x + matIn.x.y*vecIn.y + matIn.x.z*vecIn.z;
-    vecOut.y = matIn.y.x*vecIn.x + matIn.y.y*vecIn.y + matIn.y.z*vecIn.z;
-    vecOut.z = matIn.x.x*vecIn.x + matIn.z.y*vecIn.y + matIn.z.z*vecIn.z;
-    return vecOut;
-}
-
-// overload % operator to provide a vector cross product
-Vector3f operator%( Vector3f vecIn1, Vector3f vecIn2)
-{
-    Vector3f vecOut;
-    vecOut.x = vecIn1.y*vecIn2.z - vecIn1.z*vecIn2.y;
-    vecOut.y = vecIn1.z*vecIn2.x - vecIn1.x*vecIn2.z;
-    vecOut.z = vecIn1.x*vecIn2.y - vecIn1.y*vecIn2.x;
-    return vecOut;
-}
-
-// overload * operator to provide a vector scaler product
-Vector3f operator*(Vector3f vecIn1, float sclIn1)
-{
-    Vector3f vecOut;
-    vecOut.x = vecIn1.x * sclIn1;
-    vecOut.y = vecIn1.y * sclIn1;
-    vecOut.z = vecIn1.z * sclIn1;
-    return vecOut;
-}
-
-// overload * operator to provide a vector scaler product
-Vector3f operator*(float sclIn1, Vector3f vecIn1)
-{
-    Vector3f vecOut;
-    vecOut.x = vecIn1.x * sclIn1;
-    vecOut.y = vecIn1.y * sclIn1;
-    vecOut.z = vecIn1.z * sclIn1;
-    return vecOut;
-}
-
-void swap_var(float &d1, float &d2)
-{
-    float tmp = d1;
-    d1 = d2;
-    d2 = tmp;
-}
-
-AttPosEKF::AttPosEKF() :
-    fusionModeGPS(0),
-    covSkipCount(0),
-    EAS2TAS(1.0f),
-    statesInitialised(false),
-    fuseVelData(false),
-    fusePosData(false),
-    fuseHgtData(false),
-    fuseMagData(false),
-    fuseVtasData(false),
-    onGround(true),
-    staticMode(true),
-    useAirspeed(true),
-    useCompass(true),
-    numericalProtection(true),
-    storeIndex(0)
-{
-
-}
-
-AttPosEKF::~AttPosEKF()
-{
-}
-
-void AttPosEKF::UpdateStrapdownEquationsNED()
-{
-    Vector3f delVelNav;
-    float q00;
-    float q11;
-    float q22;
-    float q33;
-    float q01;
-    float q02;
-    float q03;
-    float q12;
-    float q13;
-    float q23;
-    Mat3f Tbn;
-    Mat3f Tnb;
-    float rotationMag;
-    float qUpdated[4];
-    float quatMag;
-    float deltaQuat[4];
-    const Vector3f gravityNED = {0.0,0.0,GRAVITY_MSS};
-
-// Remove sensor bias errors
-    correctedDelAng.x = dAngIMU.x - states[10];
-    correctedDelAng.y = dAngIMU.y - states[11];
-    correctedDelAng.z = dAngIMU.z - states[12];
-    dVelIMU.x = dVelIMU.x;
-    dVelIMU.y = dVelIMU.y;
-    dVelIMU.z = dVelIMU.z;
-
-// Save current measurements
-    Vector3f  prevDelAng = correctedDelAng;
-
-// Apply corrections for earths rotation rate and coning errors
-// * and + operators have been overloaded
-    correctedDelAng   = correctedDelAng - Tnb*earthRateNED*dtIMU + 8.333333333333333e-2f*(prevDelAng % correctedDelAng);
-
-// Convert the rotation vector to its equivalent quaternion
-    rotationMag = correctedDelAng.length();
-    if (rotationMag < 1e-12f)
-    {
-        deltaQuat[0] = 1.0;
-        deltaQuat[1] = 0.0;
-        deltaQuat[2] = 0.0;
-        deltaQuat[3] = 0.0;
-    }
-    else
-    {
-        deltaQuat[0] = cos(0.5f*rotationMag);
-        float rotScaler = (sin(0.5f*rotationMag))/rotationMag;
-        deltaQuat[1] = correctedDelAng.x*rotScaler;
-        deltaQuat[2] = correctedDelAng.y*rotScaler;
-        deltaQuat[3] = correctedDelAng.z*rotScaler;
-    }
-
-// Update the quaternions by rotating from the previous attitude through
-// the delta angle rotation quaternion
-    qUpdated[0] = states[0]*deltaQuat[0] - states[1]*deltaQuat[1] - states[2]*deltaQuat[2] - states[3]*deltaQuat[3];
-    qUpdated[1] = states[0]*deltaQuat[1] + states[1]*deltaQuat[0] + states[2]*deltaQuat[3] - states[3]*deltaQuat[2];
-    qUpdated[2] = states[0]*deltaQuat[2] + states[2]*deltaQuat[0] + states[3]*deltaQuat[1] - states[1]*deltaQuat[3];
-    qUpdated[3] = states[0]*deltaQuat[3] + states[3]*deltaQuat[0] + states[1]*deltaQuat[2] - states[2]*deltaQuat[1];
-
-// Normalise the quaternions and update the quaternion states
-    quatMag = sqrtf(sq(qUpdated[0]) + sq(qUpdated[1]) + sq(qUpdated[2]) + sq(qUpdated[3]));
-    if (quatMag > 1e-16f)
-    {
-        float quatMagInv = 1.0f/quatMag;
-        states[0] = quatMagInv*qUpdated[0];
-        states[1] = quatMagInv*qUpdated[1];
-        states[2] = quatMagInv*qUpdated[2];
-        states[3] = quatMagInv*qUpdated[3];
-    }
-
-// Calculate the body to nav cosine matrix
-    q00 = sq(states[0]);
-    q11 = sq(states[1]);
-    q22 = sq(states[2]);
-    q33 = sq(states[3]);
-    q01 =  states[0]*states[1];
-    q02 =  states[0]*states[2];
-    q03 =  states[0]*states[3];
-    q12 =  states[1]*states[2];
-    q13 =  states[1]*states[3];
-    q23 =  states[2]*states[3];
-
-    Tbn.x.x = q00 + q11 - q22 - q33;
-    Tbn.y.y = q00 - q11 + q22 - q33;
-    Tbn.z.z = q00 - q11 - q22 + q33;
-    Tbn.x.y = 2*(q12 - q03);
-    Tbn.x.z = 2*(q13 + q02);
-    Tbn.y.x = 2*(q12 + q03);
-    Tbn.y.z = 2*(q23 - q01);
-    Tbn.z.x = 2*(q13 - q02);
-    Tbn.z.y = 2*(q23 + q01);
-
-    Tnb = Tbn.transpose();
-
-// transform body delta velocities to delta velocities in the nav frame
-// * and + operators have been overloaded
-    //delVelNav = Tbn*dVelIMU + gravityNED*dtIMU;
-    delVelNav.x = Tbn.x.x*dVelIMU.x + Tbn.x.y*dVelIMU.y + Tbn.x.z*dVelIMU.z + gravityNED.x*dtIMU;
-    delVelNav.y = Tbn.y.x*dVelIMU.x + Tbn.y.y*dVelIMU.y + Tbn.y.z*dVelIMU.z + gravityNED.y*dtIMU;
-    delVelNav.z = Tbn.z.x*dVelIMU.x + Tbn.z.y*dVelIMU.y + Tbn.z.z*dVelIMU.z + gravityNED.z*dtIMU;
-
-// calculate the magnitude of the nav acceleration (required for GPS
-// variance estimation)
-    accNavMag = delVelNav.length()/dtIMU;
-
-// If calculating position save previous velocity
-    float lastVelocity[3];
-    lastVelocity[0] = states[4];
-    lastVelocity[1] = states[5];
-    lastVelocity[2] = states[6];
-
-// Sum delta velocities to get velocity
-    states[4] = states[4] + delVelNav.x;
-    states[5] = states[5] + delVelNav.y;
-    states[6] = states[6] + delVelNav.z;
-
-// If calculating postions, do a trapezoidal integration for position
-    states[7] = states[7] + 0.5f*(states[4] + lastVelocity[0])*dtIMU;
-    states[8] = states[8] + 0.5f*(states[5] + lastVelocity[1])*dtIMU;
-    states[9] = states[9] + 0.5f*(states[6] + lastVelocity[2])*dtIMU;
-
-    // Constrain states (to protect against filter divergence)
-    ConstrainStates();
-}
-
-void AttPosEKF::CovariancePrediction(float dt)
-{
-    // scalars
-    float windVelSigma;
-    float dAngBiasSigma;
-    // float dVelBiasSigma;
-    float magEarthSigma;
-    float magBodySigma;
-    float daxCov;
-    float dayCov;
-    float dazCov;
-    float dvxCov;
-    float dvyCov;
-    float dvzCov;
-    float dvx;
-    float dvy;
-    float dvz;
-    float dax;
-    float day;
-    float daz;
-    float q0;
-    float q1;
-    float q2;
-    float q3;
-    float dax_b;
-    float day_b;
-    float daz_b;
-
-    // arrays
-    float processNoise[21];
-    float SF[14];
-    float SG[8];
-    float SQ[11];
-    float SPP[13] = {0};
-    float nextP[21][21];
-
-    // calculate covariance prediction process noise
-    const float yawVarScale = 1.0f;
-    windVelSigma = dt*0.1f;
-    dAngBiasSigma = dt*5.0e-7f;
-    magEarthSigma = dt*3.0e-4f;
-    magBodySigma  = dt*3.0e-4f;
-    for (uint8_t i= 0; i<=9; i++) processNoise[i]  = 1.0e-9f;
-    for (uint8_t i=10; i<=12; i++) processNoise[i] = dAngBiasSigma;
-    if (onGround) processNoise[12] = dAngBiasSigma * yawVarScale;
-    for (uint8_t i=13; i<=14; i++) processNoise[i] = windVelSigma;
-    for (uint8_t i=15; i<=17; i++) processNoise[i] = magEarthSigma;
-    for (uint8_t i=18; i<=20; i++) processNoise[i] = magBodySigma;
-    for (uint8_t i= 0; i<=20; i++) processNoise[i] = sq(processNoise[i]);
-
-    // set variables used to calculate covariance growth
-    dvx = summedDelVel.x;
-    dvy = summedDelVel.y;
-    dvz = summedDelVel.z;
-    dax = summedDelAng.x;
-    day = summedDelAng.y;
-    daz = summedDelAng.z;
-    q0 = states[0];
-    q1 = states[1];
-    q2 = states[2];
-    q3 = states[3];
-    dax_b = states[10];
-    day_b = states[11];
-    daz_b = states[12];
-    daxCov = sq(dt*1.4544411e-2f);
-    dayCov = sq(dt*1.4544411e-2f);
-    dazCov = sq(dt*1.4544411e-2f);
-    if (onGround) dazCov = dazCov * sq(yawVarScale);
-    dvxCov = sq(dt*0.5f);
-    dvyCov = sq(dt*0.5f);
-    dvzCov = sq(dt*0.5f);
-
-    // Predicted covariance calculation
-    SF[0] = 2*dvx*q1 + 2*dvy*q2 + 2*dvz*q3;
-    SF[1] = 2*dvx*q3 + 2*dvy*q0 - 2*dvz*q1;
-    SF[2] = 2*dvx*q0 - 2*dvy*q3 + 2*dvz*q2;
-    SF[3] = day/2 - day_b/2;
-    SF[4] = daz/2 - daz_b/2;
-    SF[5] = dax/2 - dax_b/2;
-    SF[6] = dax_b/2 - dax/2;
-    SF[7] = daz_b/2 - daz/2;
-    SF[8] = day_b/2 - day/2;
-    SF[9] = q1/2;
-    SF[10] = q2/2;
-    SF[11] = q3/2;
-    SF[12] = 2*dvz*q0;
-    SF[13] = 2*dvy*q1;
-
-    SG[0] = q0/2;
-    SG[1] = sq(q3);
-    SG[2] = sq(q2);
-    SG[3] = sq(q1);
-    SG[4] = sq(q0);
-    SG[5] = 2*q2*q3;
-    SG[6] = 2*q1*q3;
-    SG[7] = 2*q1*q2;
-
-    SQ[0] = dvzCov*(SG[5] - 2*q0*q1)*(SG[1] - SG[2] - SG[3] + SG[4]) - dvyCov*(SG[5] + 2*q0*q1)*(SG[1] - SG[2] + SG[3] - SG[4]) + dvxCov*(SG[6] - 2*q0*q2)*(SG[7] + 2*q0*q3);
-    SQ[1] = dvzCov*(SG[6] + 2*q0*q2)*(SG[1] - SG[2] - SG[3] + SG[4]) - dvxCov*(SG[6] - 2*q0*q2)*(SG[1] + SG[2] - SG[3] - SG[4]) + dvyCov*(SG[5] + 2*q0*q1)*(SG[7] - 2*q0*q3);
-    SQ[2] = dvzCov*(SG[5] - 2*q0*q1)*(SG[6] + 2*q0*q2) - dvyCov*(SG[7] - 2*q0*q3)*(SG[1] - SG[2] + SG[3] - SG[4]) - dvxCov*(SG[7] + 2*q0*q3)*(SG[1] + SG[2] - SG[3] - SG[4]);
-    SQ[3] = (dayCov*q1*SG[0])/2 - (dazCov*q1*SG[0])/2 - (daxCov*q2*q3)/4;
-    SQ[4] = (dazCov*q2*SG[0])/2 - (daxCov*q2*SG[0])/2 - (dayCov*q1*q3)/4;
-    SQ[5] = (daxCov*q3*SG[0])/2 - (dayCov*q3*SG[0])/2 - (dazCov*q1*q2)/4;
-    SQ[6] = (daxCov*q1*q2)/4 - (dazCov*q3*SG[0])/2 - (dayCov*q1*q2)/4;
-    SQ[7] = (dazCov*q1*q3)/4 - (daxCov*q1*q3)/4 - (dayCov*q2*SG[0])/2;
-    SQ[8] = (dayCov*q2*q3)/4 - (daxCov*q1*SG[0])/2 - (dazCov*q2*q3)/4;
-    SQ[9] = sq(SG[0]);
-    SQ[10] = sq(q1);
-
-    SPP[0] = SF[12] + SF[13] - 2*dvx*q2;
-    SPP[1] = 2*dvx*q0 - 2*dvy*q3 + 2*dvz*q2;
-    SPP[2] = 2*dvx*q3 + 2*dvy*q0 - 2*dvz*q1;
-    SPP[3] = SF[11];
-    SPP[4] = SF[10];
-    SPP[5] = SF[9];
-    SPP[6] = SF[7];
-    SPP[7] = SF[8];
-
-    nextP[0][0] = P[0][0] + P[1][0]*SF[6] + P[2][0]*SPP[7] + P[3][0]*SPP[6] + P[10][0]*SPP[5] + P[11][0]*SPP[4] + P[12][0]*SPP[3] + (daxCov*SQ[10])/4 + SF[6]*(P[0][1] + P[1][1]*SF[6] + P[2][1]*SPP[7] + P[3][1]*SPP[6] + P[10][1]*SPP[5] + P[11][1]*SPP[4] + P[12][1]*SPP[3]) + SPP[7]*(P[0][2] + P[1][2]*SF[6] + P[2][2]*SPP[7] + P[3][2]*SPP[6] + P[10][2]*SPP[5] + P[11][2]*SPP[4] + P[12][2]*SPP[3]) + SPP[6]*(P[0][3] + P[1][3]*SF[6] + P[2][3]*SPP[7] + P[3][3]*SPP[6] + P[10][3]*SPP[5] + P[11][3]*SPP[4] + P[12][3]*SPP[3]) + SPP[5]*(P[0][10] + P[1][10]*SF[6] + P[2][10]*SPP[7] + P[3][10]*SPP[6] + P[10][10]*SPP[5] + P[11][10]*SPP[4] + P[12][10]*SPP[3]) + SPP[4]*(P[0][11] + P[1][11]*SF[6] + P[2][11]*SPP[7] + P[3][11]*SPP[6] + P[10][11]*SPP[5] + P[11][11]*SPP[4] + P[12][11]*SPP[3]) + SPP[3]*(P[0][12] + P[1][12]*SF[6] + P[2][12]*SPP[7] + P[3][12]*SPP[6] + P[10][12]*SPP[5] + P[11][12]*SPP[4] + P[12][12]*SPP[3]) + (dayCov*sq(q2))/4 + (dazCov*sq(q3))/4;
-    nextP[0][1] = P[0][1] + SQ[8] + P[1][1]*SF[6] + P[2][1]*SPP[7] + P[3][1]*SPP[6] + P[10][1]*SPP[5] + P[11][1]*SPP[4] + P[12][1]*SPP[3] + SF[5]*(P[0][0] + P[1][0]*SF[6] + P[2][0]*SPP[7] + P[3][0]*SPP[6] + P[10][0]*SPP[5] + P[11][0]*SPP[4] + P[12][0]*SPP[3]) + SF[4]*(P[0][2] + P[1][2]*SF[6] + P[2][2]*SPP[7] + P[3][2]*SPP[6] + P[10][2]*SPP[5] + P[11][2]*SPP[4] + P[12][2]*SPP[3]) + SPP[7]*(P[0][3] + P[1][3]*SF[6] + P[2][3]*SPP[7] + P[3][3]*SPP[6] + P[10][3]*SPP[5] + P[11][3]*SPP[4] + P[12][3]*SPP[3]) + SPP[3]*(P[0][11] + P[1][11]*SF[6] + P[2][11]*SPP[7] + P[3][11]*SPP[6] + P[10][11]*SPP[5] + P[11][11]*SPP[4] + P[12][11]*SPP[3]) - SPP[4]*(P[0][12] + P[1][12]*SF[6] + P[2][12]*SPP[7] + P[3][12]*SPP[6] + P[10][12]*SPP[5] + P[11][12]*SPP[4] + P[12][12]*SPP[3]) - (q0*(P[0][10] + P[1][10]*SF[6] + P[2][10]*SPP[7] + P[3][10]*SPP[6] + P[10][10]*SPP[5] + P[11][10]*SPP[4] + P[12][10]*SPP[3]))/2;
-    nextP[0][2] = P[0][2] + SQ[7] + P[1][2]*SF[6] + P[2][2]*SPP[7] + P[3][2]*SPP[6] + P[10][2]*SPP[5] + P[11][2]*SPP[4] + P[12][2]*SPP[3] + SF[3]*(P[0][0] + P[1][0]*SF[6] + P[2][0]*SPP[7] + P[3][0]*SPP[6] + P[10][0]*SPP[5] + P[11][0]*SPP[4] + P[12][0]*SPP[3]) + SF[5]*(P[0][3] + P[1][3]*SF[6] + P[2][3]*SPP[7] + P[3][3]*SPP[6] + P[10][3]*SPP[5] + P[11][3]*SPP[4] + P[12][3]*SPP[3]) + SPP[6]*(P[0][1] + P[1][1]*SF[6] + P[2][1]*SPP[7] + P[3][1]*SPP[6] + P[10][1]*SPP[5] + P[11][1]*SPP[4] + P[12][1]*SPP[3]) - SPP[3]*(P[0][10] + P[1][10]*SF[6] + P[2][10]*SPP[7] + P[3][10]*SPP[6] + P[10][10]*SPP[5] + P[11][10]*SPP[4] + P[12][10]*SPP[3]) + SPP[5]*(P[0][12] + P[1][12]*SF[6] + P[2][12]*SPP[7] + P[3][12]*SPP[6] + P[10][12]*SPP[5] + P[11][12]*SPP[4] + P[12][12]*SPP[3]) - (q0*(P[0][11] + P[1][11]*SF[6] + P[2][11]*SPP[7] + P[3][11]*SPP[6] + P[10][11]*SPP[5] + P[11][11]*SPP[4] + P[12][11]*SPP[3]))/2;
-    nextP[0][3] = P[0][3] + SQ[6] + P[1][3]*SF[6] + P[2][3]*SPP[7] + P[3][3]*SPP[6] + P[10][3]*SPP[5] + P[11][3]*SPP[4] + P[12][3]*SPP[3] + SF[4]*(P[0][0] + P[1][0]*SF[6] + P[2][0]*SPP[7] + P[3][0]*SPP[6] + P[10][0]*SPP[5] + P[11][0]*SPP[4] + P[12][0]*SPP[3]) + SF[3]*(P[0][1] + P[1][1]*SF[6] + P[2][1]*SPP[7] + P[3][1]*SPP[6] + P[10][1]*SPP[5] + P[11][1]*SPP[4] + P[12][1]*SPP[3]) + SF[6]*(P[0][2] + P[1][2]*SF[6] + P[2][2]*SPP[7] + P[3][2]*SPP[6] + P[10][2]*SPP[5] + P[11][2]*SPP[4] + P[12][2]*SPP[3]) + SPP[4]*(P[0][10] + P[1][10]*SF[6] + P[2][10]*SPP[7] + P[3][10]*SPP[6] + P[10][10]*SPP[5] + P[11][10]*SPP[4] + P[12][10]*SPP[3]) - SPP[5]*(P[0][11] + P[1][11]*SF[6] + P[2][11]*SPP[7] + P[3][11]*SPP[6] + P[10][11]*SPP[5] + P[11][11]*SPP[4] + P[12][11]*SPP[3]) - (q0*(P[0][12] + P[1][12]*SF[6] + P[2][12]*SPP[7] + P[3][12]*SPP[6] + P[10][12]*SPP[5] + P[11][12]*SPP[4] + P[12][12]*SPP[3]))/2;
-    nextP[0][4] = P[0][4] + P[1][4]*SF[6] + P[2][4]*SPP[7] + P[3][4]*SPP[6] + P[10][4]*SPP[5] + P[11][4]*SPP[4] + P[12][4]*SPP[3] + SF[2]*(P[0][0] + P[1][0]*SF[6] + P[2][0]*SPP[7] + P[3][0]*SPP[6] + P[10][0]*SPP[5] + P[11][0]*SPP[4] + P[12][0]*SPP[3]) + SF[0]*(P[0][1] + P[1][1]*SF[6] + P[2][1]*SPP[7] + P[3][1]*SPP[6] + P[10][1]*SPP[5] + P[11][1]*SPP[4] + P[12][1]*SPP[3]) + SPP[0]*(P[0][2] + P[1][2]*SF[6] + P[2][2]*SPP[7] + P[3][2]*SPP[6] + P[10][2]*SPP[5] + P[11][2]*SPP[4] + P[12][2]*SPP[3]) - SPP[2]*(P[0][3] + P[1][3]*SF[6] + P[2][3]*SPP[7] + P[3][3]*SPP[6] + P[10][3]*SPP[5] + P[11][3]*SPP[4] + P[12][3]*SPP[3]);
-    nextP[0][5] = P[0][5] + P[1][5]*SF[6] + P[2][5]*SPP[7] + P[3][5]*SPP[6] + P[10][5]*SPP[5] + P[11][5]*SPP[4] + P[12][5]*SPP[3] + SF[1]*(P[0][0] + P[1][0]*SF[6] + P[2][0]*SPP[7] + P[3][0]*SPP[6] + P[10][0]*SPP[5] + P[11][0]*SPP[4] + P[12][0]*SPP[3]) + SF[0]*(P[0][2] + P[1][2]*SF[6] + P[2][2]*SPP[7] + P[3][2]*SPP[6] + P[10][2]*SPP[5] + P[11][2]*SPP[4] + P[12][2]*SPP[3]) + SF[2]*(P[0][3] + P[1][3]*SF[6] + P[2][3]*SPP[7] + P[3][3]*SPP[6] + P[10][3]*SPP[5] + P[11][3]*SPP[4] + P[12][3]*SPP[3]) - SPP[0]*(P[0][1] + P[1][1]*SF[6] + P[2][1]*SPP[7] + P[3][1]*SPP[6] + P[10][1]*SPP[5] + P[11][1]*SPP[4] + P[12][1]*SPP[3]);
-    nextP[0][6] = P[0][6] + P[1][6]*SF[6] + P[2][6]*SPP[7] + P[3][6]*SPP[6] + P[10][6]*SPP[5] + P[11][6]*SPP[4] + P[12][6]*SPP[3] + SF[1]*(P[0][1] + P[1][1]*SF[6] + P[2][1]*SPP[7] + P[3][1]*SPP[6] + P[10][1]*SPP[5] + P[11][1]*SPP[4] + P[12][1]*SPP[3]) + SF[0]*(P[0][3] + P[1][3]*SF[6] + P[2][3]*SPP[7] + P[3][3]*SPP[6] + P[10][3]*SPP[5] + P[11][3]*SPP[4] + P[12][3]*SPP[3]) + SPP[0]*(P[0][0] + P[1][0]*SF[6] + P[2][0]*SPP[7] + P[3][0]*SPP[6] + P[10][0]*SPP[5] + P[11][0]*SPP[4] + P[12][0]*SPP[3]) - SPP[1]*(P[0][2] + P[1][2]*SF[6] + P[2][2]*SPP[7] + P[3][2]*SPP[6] + P[10][2]*SPP[5] + P[11][2]*SPP[4] + P[12][2]*SPP[3]);
-    nextP[0][7] = P[0][7] + P[1][7]*SF[6] + P[2][7]*SPP[7] + P[3][7]*SPP[6] + P[10][7]*SPP[5] + P[11][7]*SPP[4] + P[12][7]*SPP[3] + dt*(P[0][4] + P[1][4]*SF[6] + P[2][4]*SPP[7] + P[3][4]*SPP[6] + P[10][4]*SPP[5] + P[11][4]*SPP[4] + P[12][4]*SPP[3]);
-    nextP[0][8] = P[0][8] + P[1][8]*SF[6] + P[2][8]*SPP[7] + P[3][8]*SPP[6] + P[10][8]*SPP[5] + P[11][8]*SPP[4] + P[12][8]*SPP[3] + dt*(P[0][5] + P[1][5]*SF[6] + P[2][5]*SPP[7] + P[3][5]*SPP[6] + P[10][5]*SPP[5] + P[11][5]*SPP[4] + P[12][5]*SPP[3]);
-    nextP[0][9] = P[0][9] + P[1][9]*SF[6] + P[2][9]*SPP[7] + P[3][9]*SPP[6] + P[10][9]*SPP[5] + P[11][9]*SPP[4] + P[12][9]*SPP[3] + dt*(P[0][6] + P[1][6]*SF[6] + P[2][6]*SPP[7] + P[3][6]*SPP[6] + P[10][6]*SPP[5] + P[11][6]*SPP[4] + P[12][6]*SPP[3]);
-    nextP[0][10] = P[0][10] + P[1][10]*SF[6] + P[2][10]*SPP[7] + P[3][10]*SPP[6] + P[10][10]*SPP[5] + P[11][10]*SPP[4] + P[12][10]*SPP[3];
-    nextP[0][11] = P[0][11] + P[1][11]*SF[6] + P[2][11]*SPP[7] + P[3][11]*SPP[6] + P[10][11]*SPP[5] + P[11][11]*SPP[4] + P[12][11]*SPP[3];
-    nextP[0][12] = P[0][12] + P[1][12]*SF[6] + P[2][12]*SPP[7] + P[3][12]*SPP[6] + P[10][12]*SPP[5] + P[11][12]*SPP[4] + P[12][12]*SPP[3];
-    nextP[0][13] = P[0][13] + P[1][13]*SF[6] + P[2][13]*SPP[7] + P[3][13]*SPP[6] + P[10][13]*SPP[5] + P[11][13]*SPP[4] + P[12][13]*SPP[3];
-    nextP[0][14] = P[0][14] + P[1][14]*SF[6] + P[2][14]*SPP[7] + P[3][14]*SPP[6] + P[10][14]*SPP[5] + P[11][14]*SPP[4] + P[12][14]*SPP[3];
-    nextP[0][15] = P[0][15] + P[1][15]*SF[6] + P[2][15]*SPP[7] + P[3][15]*SPP[6] + P[10][15]*SPP[5] + P[11][15]*SPP[4] + P[12][15]*SPP[3];
-    nextP[0][16] = P[0][16] + P[1][16]*SF[6] + P[2][16]*SPP[7] + P[3][16]*SPP[6] + P[10][16]*SPP[5] + P[11][16]*SPP[4] + P[12][16]*SPP[3];
-    nextP[0][17] = P[0][17] + P[1][17]*SF[6] + P[2][17]*SPP[7] + P[3][17]*SPP[6] + P[10][17]*SPP[5] + P[11][17]*SPP[4] + P[12][17]*SPP[3];
-    nextP[0][18] = P[0][18] + P[1][18]*SF[6] + P[2][18]*SPP[7] + P[3][18]*SPP[6] + P[10][18]*SPP[5] + P[11][18]*SPP[4] + P[12][18]*SPP[3];
-    nextP[0][19] = P[0][19] + P[1][19]*SF[6] + P[2][19]*SPP[7] + P[3][19]*SPP[6] + P[10][19]*SPP[5] + P[11][19]*SPP[4] + P[12][19]*SPP[3];
-    nextP[0][20] = P[0][20] + P[1][20]*SF[6] + P[2][20]*SPP[7] + P[3][20]*SPP[6] + P[10][20]*SPP[5] + P[11][20]*SPP[4] + P[12][20]*SPP[3];
-    nextP[1][0] = P[1][0] + SQ[8] + P[0][0]*SF[5] + P[2][0]*SF[4] + P[3][0]*SPP[7] + P[11][0]*SPP[3] - P[12][0]*SPP[4] - (P[10][0]*q0)/2 + SF[6]*(P[1][1] + P[0][1]*SF[5] + P[2][1]*SF[4] + P[3][1]*SPP[7] + P[11][1]*SPP[3] - P[12][1]*SPP[4] - (P[10][1]*q0)/2) + SPP[7]*(P[1][2] + P[0][2]*SF[5] + P[2][2]*SF[4] + P[3][2]*SPP[7] + P[11][2]*SPP[3] - P[12][2]*SPP[4] - (P[10][2]*q0)/2) + SPP[6]*(P[1][3] + P[0][3]*SF[5] + P[2][3]*SF[4] + P[3][3]*SPP[7] + P[11][3]*SPP[3] - P[12][3]*SPP[4] - (P[10][3]*q0)/2) + SPP[5]*(P[1][10] + P[0][10]*SF[5] + P[2][10]*SF[4] + P[3][10]*SPP[7] + P[11][10]*SPP[3] - P[12][10]*SPP[4] - (P[10][10]*q0)/2) + SPP[4]*(P[1][11] + P[0][11]*SF[5] + P[2][11]*SF[4] + P[3][11]*SPP[7] + P[11][11]*SPP[3] - P[12][11]*SPP[4] - (P[10][11]*q0)/2) + SPP[3]*(P[1][12] + P[0][12]*SF[5] + P[2][12]*SF[4] + P[3][12]*SPP[7] + P[11][12]*SPP[3] - P[12][12]*SPP[4] - (P[10][12]*q0)/2);
-    nextP[1][1] = P[1][1] + P[0][1]*SF[5] + P[2][1]*SF[4] + P[3][1]*SPP[7] + P[11][1]*SPP[3] - P[12][1]*SPP[4] + daxCov*SQ[9] - (P[10][1]*q0)/2 + SF[5]*(P[1][0] + P[0][0]*SF[5] + P[2][0]*SF[4] + P[3][0]*SPP[7] + P[11][0]*SPP[3] - P[12][0]*SPP[4] - (P[10][0]*q0)/2) + SF[4]*(P[1][2] + P[0][2]*SF[5] + P[2][2]*SF[4] + P[3][2]*SPP[7] + P[11][2]*SPP[3] - P[12][2]*SPP[4] - (P[10][2]*q0)/2) + SPP[7]*(P[1][3] + P[0][3]*SF[5] + P[2][3]*SF[4] + P[3][3]*SPP[7] + P[11][3]*SPP[3] - P[12][3]*SPP[4] - (P[10][3]*q0)/2) + SPP[3]*(P[1][11] + P[0][11]*SF[5] + P[2][11]*SF[4] + P[3][11]*SPP[7] + P[11][11]*SPP[3] - P[12][11]*SPP[4] - (P[10][11]*q0)/2) - SPP[4]*(P[1][12] + P[0][12]*SF[5] + P[2][12]*SF[4] + P[3][12]*SPP[7] + P[11][12]*SPP[3] - P[12][12]*SPP[4] - (P[10][12]*q0)/2) + (dayCov*sq(q3))/4 + (dazCov*sq(q2))/4 - (q0*(P[1][10] + P[0][10]*SF[5] + P[2][10]*SF[4] + P[3][10]*SPP[7] + P[11][10]*SPP[3] - P[12][10]*SPP[4] - (P[10][10]*q0)/2))/2;
-    nextP[1][2] = P[1][2] + SQ[5] + P[0][2]*SF[5] + P[2][2]*SF[4] + P[3][2]*SPP[7] + P[11][2]*SPP[3] - P[12][2]*SPP[4] - (P[10][2]*q0)/2 + SF[3]*(P[1][0] + P[0][0]*SF[5] + P[2][0]*SF[4] + P[3][0]*SPP[7] + P[11][0]*SPP[3] - P[12][0]*SPP[4] - (P[10][0]*q0)/2) + SF[5]*(P[1][3] + P[0][3]*SF[5] + P[2][3]*SF[4] + P[3][3]*SPP[7] + P[11][3]*SPP[3] - P[12][3]*SPP[4] - (P[10][3]*q0)/2) + SPP[6]*(P[1][1] + P[0][1]*SF[5] + P[2][1]*SF[4] + P[3][1]*SPP[7] + P[11][1]*SPP[3] - P[12][1]*SPP[4] - (P[10][1]*q0)/2) - SPP[3]*(P[1][10] + P[0][10]*SF[5] + P[2][10]*SF[4] + P[3][10]*SPP[7] + P[11][10]*SPP[3] - P[12][10]*SPP[4] - (P[10][10]*q0)/2) + SPP[5]*(P[1][12] + P[0][12]*SF[5] + P[2][12]*SF[4] + P[3][12]*SPP[7] + P[11][12]*SPP[3] - P[12][12]*SPP[4] - (P[10][12]*q0)/2) - (q0*(P[1][11] + P[0][11]*SF[5] + P[2][11]*SF[4] + P[3][11]*SPP[7] + P[11][11]*SPP[3] - P[12][11]*SPP[4] - (P[10][11]*q0)/2))/2;
-    nextP[1][3] = P[1][3] + SQ[4] + P[0][3]*SF[5] + P[2][3]*SF[4] + P[3][3]*SPP[7] + P[11][3]*SPP[3] - P[12][3]*SPP[4] - (P[10][3]*q0)/2 + SF[4]*(P[1][0] + P[0][0]*SF[5] + P[2][0]*SF[4] + P[3][0]*SPP[7] + P[11][0]*SPP[3] - P[12][0]*SPP[4] - (P[10][0]*q0)/2) + SF[3]*(P[1][1] + P[0][1]*SF[5] + P[2][1]*SF[4] + P[3][1]*SPP[7] + P[11][1]*SPP[3] - P[12][1]*SPP[4] - (P[10][1]*q0)/2) + SF[6]*(P[1][2] + P[0][2]*SF[5] + P[2][2]*SF[4] + P[3][2]*SPP[7] + P[11][2]*SPP[3] - P[12][2]*SPP[4] - (P[10][2]*q0)/2) + SPP[4]*(P[1][10] + P[0][10]*SF[5] + P[2][10]*SF[4] + P[3][10]*SPP[7] + P[11][10]*SPP[3] - P[12][10]*SPP[4] - (P[10][10]*q0)/2) - SPP[5]*(P[1][11] + P[0][11]*SF[5] + P[2][11]*SF[4] + P[3][11]*SPP[7] + P[11][11]*SPP[3] - P[12][11]*SPP[4] - (P[10][11]*q0)/2) - (q0*(P[1][12] + P[0][12]*SF[5] + P[2][12]*SF[4] + P[3][12]*SPP[7] + P[11][12]*SPP[3] - P[12][12]*SPP[4] - (P[10][12]*q0)/2))/2;
-    nextP[1][4] = P[1][4] + P[0][4]*SF[5] + P[2][4]*SF[4] + P[3][4]*SPP[7] + P[11][4]*SPP[3] - P[12][4]*SPP[4] - (P[10][4]*q0)/2 + SF[2]*(P[1][0] + P[0][0]*SF[5] + P[2][0]*SF[4] + P[3][0]*SPP[7] + P[11][0]*SPP[3] - P[12][0]*SPP[4] - (P[10][0]*q0)/2) + SF[0]*(P[1][1] + P[0][1]*SF[5] + P[2][1]*SF[4] + P[3][1]*SPP[7] + P[11][1]*SPP[3] - P[12][1]*SPP[4] - (P[10][1]*q0)/2) + SPP[0]*(P[1][2] + P[0][2]*SF[5] + P[2][2]*SF[4] + P[3][2]*SPP[7] + P[11][2]*SPP[3] - P[12][2]*SPP[4] - (P[10][2]*q0)/2) - SPP[2]*(P[1][3] + P[0][3]*SF[5] + P[2][3]*SF[4] + P[3][3]*SPP[7] + P[11][3]*SPP[3] - P[12][3]*SPP[4] - (P[10][3]*q0)/2);
-    nextP[1][5] = P[1][5] + P[0][5]*SF[5] + P[2][5]*SF[4] + P[3][5]*SPP[7] + P[11][5]*SPP[3] - P[12][5]*SPP[4] - (P[10][5]*q0)/2 + SF[1]*(P[1][0] + P[0][0]*SF[5] + P[2][0]*SF[4] + P[3][0]*SPP[7] + P[11][0]*SPP[3] - P[12][0]*SPP[4] - (P[10][0]*q0)/2) + SF[0]*(P[1][2] + P[0][2]*SF[5] + P[2][2]*SF[4] + P[3][2]*SPP[7] + P[11][2]*SPP[3] - P[12][2]*SPP[4] - (P[10][2]*q0)/2) + SF[2]*(P[1][3] + P[0][3]*SF[5] + P[2][3]*SF[4] + P[3][3]*SPP[7] + P[11][3]*SPP[3] - P[12][3]*SPP[4] - (P[10][3]*q0)/2) - SPP[0]*(P[1][1] + P[0][1]*SF[5] + P[2][1]*SF[4] + P[3][1]*SPP[7] + P[11][1]*SPP[3] - P[12][1]*SPP[4] - (P[10][1]*q0)/2);
-    nextP[1][6] = P[1][6] + P[0][6]*SF[5] + P[2][6]*SF[4] + P[3][6]*SPP[7] + P[11][6]*SPP[3] - P[12][6]*SPP[4] - (P[10][6]*q0)/2 + SF[1]*(P[1][1] + P[0][1]*SF[5] + P[2][1]*SF[4] + P[3][1]*SPP[7] + P[11][1]*SPP[3] - P[12][1]*SPP[4] - (P[10][1]*q0)/2) + SF[0]*(P[1][3] + P[0][3]*SF[5] + P[2][3]*SF[4] + P[3][3]*SPP[7] + P[11][3]*SPP[3] - P[12][3]*SPP[4] - (P[10][3]*q0)/2) + SPP[0]*(P[1][0] + P[0][0]*SF[5] + P[2][0]*SF[4] + P[3][0]*SPP[7] + P[11][0]*SPP[3] - P[12][0]*SPP[4] - (P[10][0]*q0)/2) - SPP[1]*(P[1][2] + P[0][2]*SF[5] + P[2][2]*SF[4] + P[3][2]*SPP[7] + P[11][2]*SPP[3] - P[12][2]*SPP[4] - (P[10][2]*q0)/2);
-    nextP[1][7] = P[1][7] + P[0][7]*SF[5] + P[2][7]*SF[4] + P[3][7]*SPP[7] + P[11][7]*SPP[3] - P[12][7]*SPP[4] - (P[10][7]*q0)/2 + dt*(P[1][4] + P[0][4]*SF[5] + P[2][4]*SF[4] + P[3][4]*SPP[7] + P[11][4]*SPP[3] - P[12][4]*SPP[4] - (P[10][4]*q0)/2);
-    nextP[1][8] = P[1][8] + P[0][8]*SF[5] + P[2][8]*SF[4] + P[3][8]*SPP[7] + P[11][8]*SPP[3] - P[12][8]*SPP[4] - (P[10][8]*q0)/2 + dt*(P[1][5] + P[0][5]*SF[5] + P[2][5]*SF[4] + P[3][5]*SPP[7] + P[11][5]*SPP[3] - P[12][5]*SPP[4] - (P[10][5]*q0)/2);
-    nextP[1][9] = P[1][9] + P[0][9]*SF[5] + P[2][9]*SF[4] + P[3][9]*SPP[7] + P[11][9]*SPP[3] - P[12][9]*SPP[4] - (P[10][9]*q0)/2 + dt*(P[1][6] + P[0][6]*SF[5] + P[2][6]*SF[4] + P[3][6]*SPP[7] + P[11][6]*SPP[3] - P[12][6]*SPP[4] - (P[10][6]*q0)/2);
-    nextP[1][10] = P[1][10] + P[0][10]*SF[5] + P[2][10]*SF[4] + P[3][10]*SPP[7] + P[11][10]*SPP[3] - P[12][10]*SPP[4] - (P[10][10]*q0)/2;
-    nextP[1][11] = P[1][11] + P[0][11]*SF[5] + P[2][11]*SF[4] + P[3][11]*SPP[7] + P[11][11]*SPP[3] - P[12][11]*SPP[4] - (P[10][11]*q0)/2;
-    nextP[1][12] = P[1][12] + P[0][12]*SF[5] + P[2][12]*SF[4] + P[3][12]*SPP[7] + P[11][12]*SPP[3] - P[12][12]*SPP[4] - (P[10][12]*q0)/2;
-    nextP[1][13] = P[1][13] + P[0][13]*SF[5] + P[2][13]*SF[4] + P[3][13]*SPP[7] + P[11][13]*SPP[3] - P[12][13]*SPP[4] - (P[10][13]*q0)/2;
-    nextP[1][14] = P[1][14] + P[0][14]*SF[5] + P[2][14]*SF[4] + P[3][14]*SPP[7] + P[11][14]*SPP[3] - P[12][14]*SPP[4] - (P[10][14]*q0)/2;
-    nextP[1][15] = P[1][15] + P[0][15]*SF[5] + P[2][15]*SF[4] + P[3][15]*SPP[7] + P[11][15]*SPP[3] - P[12][15]*SPP[4] - (P[10][15]*q0)/2;
-    nextP[1][16] = P[1][16] + P[0][16]*SF[5] + P[2][16]*SF[4] + P[3][16]*SPP[7] + P[11][16]*SPP[3] - P[12][16]*SPP[4] - (P[10][16]*q0)/2;
-    nextP[1][17] = P[1][17] + P[0][17]*SF[5] + P[2][17]*SF[4] + P[3][17]*SPP[7] + P[11][17]*SPP[3] - P[12][17]*SPP[4] - (P[10][17]*q0)/2;
-    nextP[1][18] = P[1][18] + P[0][18]*SF[5] + P[2][18]*SF[4] + P[3][18]*SPP[7] + P[11][18]*SPP[3] - P[12][18]*SPP[4] - (P[10][18]*q0)/2;
-    nextP[1][19] = P[1][19] + P[0][19]*SF[5] + P[2][19]*SF[4] + P[3][19]*SPP[7] + P[11][19]*SPP[3] - P[12][19]*SPP[4] - (P[10][19]*q0)/2;
-    nextP[1][20] = P[1][20] + P[0][20]*SF[5] + P[2][20]*SF[4] + P[3][20]*SPP[7] + P[11][20]*SPP[3] - P[12][20]*SPP[4] - (P[10][20]*q0)/2;
-    nextP[2][0] = P[2][0] + SQ[7] + P[0][0]*SF[3] + P[3][0]*SF[5] + P[1][0]*SPP[6] - P[10][0]*SPP[3] + P[12][0]*SPP[5] - (P[11][0]*q0)/2 + SF[6]*(P[2][1] + P[0][1]*SF[3] + P[3][1]*SF[5] + P[1][1]*SPP[6] - P[10][1]*SPP[3] + P[12][1]*SPP[5] - (P[11][1]*q0)/2) + SPP[7]*(P[2][2] + P[0][2]*SF[3] + P[3][2]*SF[5] + P[1][2]*SPP[6] - P[10][2]*SPP[3] + P[12][2]*SPP[5] - (P[11][2]*q0)/2) + SPP[6]*(P[2][3] + P[0][3]*SF[3] + P[3][3]*SF[5] + P[1][3]*SPP[6] - P[10][3]*SPP[3] + P[12][3]*SPP[5] - (P[11][3]*q0)/2) + SPP[5]*(P[2][10] + P[0][10]*SF[3] + P[3][10]*SF[5] + P[1][10]*SPP[6] - P[10][10]*SPP[3] + P[12][10]*SPP[5] - (P[11][10]*q0)/2) + SPP[4]*(P[2][11] + P[0][11]*SF[3] + P[3][11]*SF[5] + P[1][11]*SPP[6] - P[10][11]*SPP[3] + P[12][11]*SPP[5] - (P[11][11]*q0)/2) + SPP[3]*(P[2][12] + P[0][12]*SF[3] + P[3][12]*SF[5] + P[1][12]*SPP[6] - P[10][12]*SPP[3] + P[12][12]*SPP[5] - (P[11][12]*q0)/2);
-    nextP[2][1] = P[2][1] + SQ[5] + P[0][1]*SF[3] + P[3][1]*SF[5] + P[1][1]*SPP[6] - P[10][1]*SPP[3] + P[12][1]*SPP[5] - (P[11][1]*q0)/2 + SF[5]*(P[2][0] + P[0][0]*SF[3] + P[3][0]*SF[5] + P[1][0]*SPP[6] - P[10][0]*SPP[3] + P[12][0]*SPP[5] - (P[11][0]*q0)/2) + SF[4]*(P[2][2] + P[0][2]*SF[3] + P[3][2]*SF[5] + P[1][2]*SPP[6] - P[10][2]*SPP[3] + P[12][2]*SPP[5] - (P[11][2]*q0)/2) + SPP[7]*(P[2][3] + P[0][3]*SF[3] + P[3][3]*SF[5] + P[1][3]*SPP[6] - P[10][3]*SPP[3] + P[12][3]*SPP[5] - (P[11][3]*q0)/2) + SPP[3]*(P[2][11] + P[0][11]*SF[3] + P[3][11]*SF[5] + P[1][11]*SPP[6] - P[10][11]*SPP[3] + P[12][11]*SPP[5] - (P[11][11]*q0)/2) - SPP[4]*(P[2][12] + P[0][12]*SF[3] + P[3][12]*SF[5] + P[1][12]*SPP[6] - P[10][12]*SPP[3] + P[12][12]*SPP[5] - (P[11][12]*q0)/2) - (q0*(P[2][10] + P[0][10]*SF[3] + P[3][10]*SF[5] + P[1][10]*SPP[6] - P[10][10]*SPP[3] + P[12][10]*SPP[5] - (P[11][10]*q0)/2))/2;
-    nextP[2][2] = P[2][2] + P[0][2]*SF[3] + P[3][2]*SF[5] + P[1][2]*SPP[6] - P[10][2]*SPP[3] + P[12][2]*SPP[5] + dayCov*SQ[9] + (dazCov*SQ[10])/4 - (P[11][2]*q0)/2 + SF[3]*(P[2][0] + P[0][0]*SF[3] + P[3][0]*SF[5] + P[1][0]*SPP[6] - P[10][0]*SPP[3] + P[12][0]*SPP[5] - (P[11][0]*q0)/2) + SF[5]*(P[2][3] + P[0][3]*SF[3] + P[3][3]*SF[5] + P[1][3]*SPP[6] - P[10][3]*SPP[3] + P[12][3]*SPP[5] - (P[11][3]*q0)/2) + SPP[6]*(P[2][1] + P[0][1]*SF[3] + P[3][1]*SF[5] + P[1][1]*SPP[6] - P[10][1]*SPP[3] + P[12][1]*SPP[5] - (P[11][1]*q0)/2) - SPP[3]*(P[2][10] + P[0][10]*SF[3] + P[3][10]*SF[5] + P[1][10]*SPP[6] - P[10][10]*SPP[3] + P[12][10]*SPP[5] - (P[11][10]*q0)/2) + SPP[5]*(P[2][12] + P[0][12]*SF[3] + P[3][12]*SF[5] + P[1][12]*SPP[6] - P[10][12]*SPP[3] + P[12][12]*SPP[5] - (P[11][12]*q0)/2) + (daxCov*sq(q3))/4 - (q0*(P[2][11] + P[0][11]*SF[3] + P[3][11]*SF[5] + P[1][11]*SPP[6] - P[10][11]*SPP[3] + P[12][11]*SPP[5] - (P[11][11]*q0)/2))/2;
-    nextP[2][3] = P[2][3] + SQ[3] + P[0][3]*SF[3] + P[3][3]*SF[5] + P[1][3]*SPP[6] - P[10][3]*SPP[3] + P[12][3]*SPP[5] - (P[11][3]*q0)/2 + SF[4]*(P[2][0] + P[0][0]*SF[3] + P[3][0]*SF[5] + P[1][0]*SPP[6] - P[10][0]*SPP[3] + P[12][0]*SPP[5] - (P[11][0]*q0)/2) + SF[3]*(P[2][1] + P[0][1]*SF[3] + P[3][1]*SF[5] + P[1][1]*SPP[6] - P[10][1]*SPP[3] + P[12][1]*SPP[5] - (P[11][1]*q0)/2) + SF[6]*(P[2][2] + P[0][2]*SF[3] + P[3][2]*SF[5] + P[1][2]*SPP[6] - P[10][2]*SPP[3] + P[12][2]*SPP[5] - (P[11][2]*q0)/2) + SPP[4]*(P[2][10] + P[0][10]*SF[3] + P[3][10]*SF[5] + P[1][10]*SPP[6] - P[10][10]*SPP[3] + P[12][10]*SPP[5] - (P[11][10]*q0)/2) - SPP[5]*(P[2][11] + P[0][11]*SF[3] + P[3][11]*SF[5] + P[1][11]*SPP[6] - P[10][11]*SPP[3] + P[12][11]*SPP[5] - (P[11][11]*q0)/2) - (q0*(P[2][12] + P[0][12]*SF[3] + P[3][12]*SF[5] + P[1][12]*SPP[6] - P[10][12]*SPP[3] + P[12][12]*SPP[5] - (P[11][12]*q0)/2))/2;
-    nextP[2][4] = P[2][4] + P[0][4]*SF[3] + P[3][4]*SF[5] + P[1][4]*SPP[6] - P[10][4]*SPP[3] + P[12][4]*SPP[5] - (P[11][4]*q0)/2 + SF[2]*(P[2][0] + P[0][0]*SF[3] + P[3][0]*SF[5] + P[1][0]*SPP[6] - P[10][0]*SPP[3] + P[12][0]*SPP[5] - (P[11][0]*q0)/2) + SF[0]*(P[2][1] + P[0][1]*SF[3] + P[3][1]*SF[5] + P[1][1]*SPP[6] - P[10][1]*SPP[3] + P[12][1]*SPP[5] - (P[11][1]*q0)/2) + SPP[0]*(P[2][2] + P[0][2]*SF[3] + P[3][2]*SF[5] + P[1][2]*SPP[6] - P[10][2]*SPP[3] + P[12][2]*SPP[5] - (P[11][2]*q0)/2) - SPP[2]*(P[2][3] + P[0][3]*SF[3] + P[3][3]*SF[5] + P[1][3]*SPP[6] - P[10][3]*SPP[3] + P[12][3]*SPP[5] - (P[11][3]*q0)/2);
-    nextP[2][5] = P[2][5] + P[0][5]*SF[3] + P[3][5]*SF[5] + P[1][5]*SPP[6] - P[10][5]*SPP[3] + P[12][5]*SPP[5] - (P[11][5]*q0)/2 + SF[1]*(P[2][0] + P[0][0]*SF[3] + P[3][0]*SF[5] + P[1][0]*SPP[6] - P[10][0]*SPP[3] + P[12][0]*SPP[5] - (P[11][0]*q0)/2) + SF[0]*(P[2][2] + P[0][2]*SF[3] + P[3][2]*SF[5] + P[1][2]*SPP[6] - P[10][2]*SPP[3] + P[12][2]*SPP[5] - (P[11][2]*q0)/2) + SF[2]*(P[2][3] + P[0][3]*SF[3] + P[3][3]*SF[5] + P[1][3]*SPP[6] - P[10][3]*SPP[3] + P[12][3]*SPP[5] - (P[11][3]*q0)/2) - SPP[0]*(P[2][1] + P[0][1]*SF[3] + P[3][1]*SF[5] + P[1][1]*SPP[6] - P[10][1]*SPP[3] + P[12][1]*SPP[5] - (P[11][1]*q0)/2);
-    nextP[2][6] = P[2][6] + P[0][6]*SF[3] + P[3][6]*SF[5] + P[1][6]*SPP[6] - P[10][6]*SPP[3] + P[12][6]*SPP[5] - (P[11][6]*q0)/2 + SF[1]*(P[2][1] + P[0][1]*SF[3] + P[3][1]*SF[5] + P[1][1]*SPP[6] - P[10][1]*SPP[3] + P[12][1]*SPP[5] - (P[11][1]*q0)/2) + SF[0]*(P[2][3] + P[0][3]*SF[3] + P[3][3]*SF[5] + P[1][3]*SPP[6] - P[10][3]*SPP[3] + P[12][3]*SPP[5] - (P[11][3]*q0)/2) + SPP[0]*(P[2][0] + P[0][0]*SF[3] + P[3][0]*SF[5] + P[1][0]*SPP[6] - P[10][0]*SPP[3] + P[12][0]*SPP[5] - (P[11][0]*q0)/2) - SPP[1]*(P[2][2] + P[0][2]*SF[3] + P[3][2]*SF[5] + P[1][2]*SPP[6] - P[10][2]*SPP[3] + P[12][2]*SPP[5] - (P[11][2]*q0)/2);
-    nextP[2][7] = P[2][7] + P[0][7]*SF[3] + P[3][7]*SF[5] + P[1][7]*SPP[6] - P[10][7]*SPP[3] + P[12][7]*SPP[5] - (P[11][7]*q0)/2 + dt*(P[2][4] + P[0][4]*SF[3] + P[3][4]*SF[5] + P[1][4]*SPP[6] - P[10][4]*SPP[3] + P[12][4]*SPP[5] - (P[11][4]*q0)/2);
-    nextP[2][8] = P[2][8] + P[0][8]*SF[3] + P[3][8]*SF[5] + P[1][8]*SPP[6] - P[10][8]*SPP[3] + P[12][8]*SPP[5] - (P[11][8]*q0)/2 + dt*(P[2][5] + P[0][5]*SF[3] + P[3][5]*SF[5] + P[1][5]*SPP[6] - P[10][5]*SPP[3] + P[12][5]*SPP[5] - (P[11][5]*q0)/2);
-    nextP[2][9] = P[2][9] + P[0][9]*SF[3] + P[3][9]*SF[5] + P[1][9]*SPP[6] - P[10][9]*SPP[3] + P[12][9]*SPP[5] - (P[11][9]*q0)/2 + dt*(P[2][6] + P[0][6]*SF[3] + P[3][6]*SF[5] + P[1][6]*SPP[6] - P[10][6]*SPP[3] + P[12][6]*SPP[5] - (P[11][6]*q0)/2);
-    nextP[2][10] = P[2][10] + P[0][10]*SF[3] + P[3][10]*SF[5] + P[1][10]*SPP[6] - P[10][10]*SPP[3] + P[12][10]*SPP[5] - (P[11][10]*q0)/2;
-    nextP[2][11] = P[2][11] + P[0][11]*SF[3] + P[3][11]*SF[5] + P[1][11]*SPP[6] - P[10][11]*SPP[3] + P[12][11]*SPP[5] - (P[11][11]*q0)/2;
-    nextP[2][12] = P[2][12] + P[0][12]*SF[3] + P[3][12]*SF[5] + P[1][12]*SPP[6] - P[10][12]*SPP[3] + P[12][12]*SPP[5] - (P[11][12]*q0)/2;
-    nextP[2][13] = P[2][13] + P[0][13]*SF[3] + P[3][13]*SF[5] + P[1][13]*SPP[6] - P[10][13]*SPP[3] + P[12][13]*SPP[5] - (P[11][13]*q0)/2;
-    nextP[2][14] = P[2][14] + P[0][14]*SF[3] + P[3][14]*SF[5] + P[1][14]*SPP[6] - P[10][14]*SPP[3] + P[12][14]*SPP[5] - (P[11][14]*q0)/2;
-    nextP[2][15] = P[2][15] + P[0][15]*SF[3] + P[3][15]*SF[5] + P[1][15]*SPP[6] - P[10][15]*SPP[3] + P[12][15]*SPP[5] - (P[11][15]*q0)/2;
-    nextP[2][16] = P[2][16] + P[0][16]*SF[3] + P[3][16]*SF[5] + P[1][16]*SPP[6] - P[10][16]*SPP[3] + P[12][16]*SPP[5] - (P[11][16]*q0)/2;
-    nextP[2][17] = P[2][17] + P[0][17]*SF[3] + P[3][17]*SF[5] + P[1][17]*SPP[6] - P[10][17]*SPP[3] + P[12][17]*SPP[5] - (P[11][17]*q0)/2;
-    nextP[2][18] = P[2][18] + P[0][18]*SF[3] + P[3][18]*SF[5] + P[1][18]*SPP[6] - P[10][18]*SPP[3] + P[12][18]*SPP[5] - (P[11][18]*q0)/2;
-    nextP[2][19] = P[2][19] + P[0][19]*SF[3] + P[3][19]*SF[5] + P[1][19]*SPP[6] - P[10][19]*SPP[3] + P[12][19]*SPP[5] - (P[11][19]*q0)/2;
-    nextP[2][20] = P[2][20] + P[0][20]*SF[3] + P[3][20]*SF[5] + P[1][20]*SPP[6] - P[10][20]*SPP[3] + P[12][20]*SPP[5] - (P[11][20]*q0)/2;
-    nextP[3][0] = P[3][0] + SQ[6] + P[0][0]*SF[4] + P[1][0]*SF[3] + P[2][0]*SF[6] + P[10][0]*SPP[4] - P[11][0]*SPP[5] - (P[12][0]*q0)/2 + SF[6]*(P[3][1] + P[0][1]*SF[4] + P[1][1]*SF[3] + P[2][1]*SF[6] + P[10][1]*SPP[4] - P[11][1]*SPP[5] - (P[12][1]*q0)/2) + SPP[7]*(P[3][2] + P[0][2]*SF[4] + P[1][2]*SF[3] + P[2][2]*SF[6] + P[10][2]*SPP[4] - P[11][2]*SPP[5] - (P[12][2]*q0)/2) + SPP[6]*(P[3][3] + P[0][3]*SF[4] + P[1][3]*SF[3] + P[2][3]*SF[6] + P[10][3]*SPP[4] - P[11][3]*SPP[5] - (P[12][3]*q0)/2) + SPP[5]*(P[3][10] + P[0][10]*SF[4] + P[1][10]*SF[3] + P[2][10]*SF[6] + P[10][10]*SPP[4] - P[11][10]*SPP[5] - (P[12][10]*q0)/2) + SPP[4]*(P[3][11] + P[0][11]*SF[4] + P[1][11]*SF[3] + P[2][11]*SF[6] + P[10][11]*SPP[4] - P[11][11]*SPP[5] - (P[12][11]*q0)/2) + SPP[3]*(P[3][12] + P[0][12]*SF[4] + P[1][12]*SF[3] + P[2][12]*SF[6] + P[10][12]*SPP[4] - P[11][12]*SPP[5] - (P[12][12]*q0)/2);
-    nextP[3][1] = P[3][1] + SQ[4] + P[0][1]*SF[4] + P[1][1]*SF[3] + P[2][1]*SF[6] + P[10][1]*SPP[4] - P[11][1]*SPP[5] - (P[12][1]*q0)/2 + SF[5]*(P[3][0] + P[0][0]*SF[4] + P[1][0]*SF[3] + P[2][0]*SF[6] + P[10][0]*SPP[4] - P[11][0]*SPP[5] - (P[12][0]*q0)/2) + SF[4]*(P[3][2] + P[0][2]*SF[4] + P[1][2]*SF[3] + P[2][2]*SF[6] + P[10][2]*SPP[4] - P[11][2]*SPP[5] - (P[12][2]*q0)/2) + SPP[7]*(P[3][3] + P[0][3]*SF[4] + P[1][3]*SF[3] + P[2][3]*SF[6] + P[10][3]*SPP[4] - P[11][3]*SPP[5] - (P[12][3]*q0)/2) + SPP[3]*(P[3][11] + P[0][11]*SF[4] + P[1][11]*SF[3] + P[2][11]*SF[6] + P[10][11]*SPP[4] - P[11][11]*SPP[5] - (P[12][11]*q0)/2) - SPP[4]*(P[3][12] + P[0][12]*SF[4] + P[1][12]*SF[3] + P[2][12]*SF[6] + P[10][12]*SPP[4] - P[11][12]*SPP[5] - (P[12][12]*q0)/2) - (q0*(P[3][10] + P[0][10]*SF[4] + P[1][10]*SF[3] + P[2][10]*SF[6] + P[10][10]*SPP[4] - P[11][10]*SPP[5] - (P[12][10]*q0)/2))/2;
-    nextP[3][2] = P[3][2] + SQ[3] + P[0][2]*SF[4] + P[1][2]*SF[3] + P[2][2]*SF[6] + P[10][2]*SPP[4] - P[11][2]*SPP[5] - (P[12][2]*q0)/2 + SF[3]*(P[3][0] + P[0][0]*SF[4] + P[1][0]*SF[3] + P[2][0]*SF[6] + P[10][0]*SPP[4] - P[11][0]*SPP[5] - (P[12][0]*q0)/2) + SF[5]*(P[3][3] + P[0][3]*SF[4] + P[1][3]*SF[3] + P[2][3]*SF[6] + P[10][3]*SPP[4] - P[11][3]*SPP[5] - (P[12][3]*q0)/2) + SPP[6]*(P[3][1] + P[0][1]*SF[4] + P[1][1]*SF[3] + P[2][1]*SF[6] + P[10][1]*SPP[4] - P[11][1]*SPP[5] - (P[12][1]*q0)/2) - SPP[3]*(P[3][10] + P[0][10]*SF[4] + P[1][10]*SF[3] + P[2][10]*SF[6] + P[10][10]*SPP[4] - P[11][10]*SPP[5] - (P[12][10]*q0)/2) + SPP[5]*(P[3][12] + P[0][12]*SF[4] + P[1][12]*SF[3] + P[2][12]*SF[6] + P[10][12]*SPP[4] - P[11][12]*SPP[5] - (P[12][12]*q0)/2) - (q0*(P[3][11] + P[0][11]*SF[4] + P[1][11]*SF[3] + P[2][11]*SF[6] + P[10][11]*SPP[4] - P[11][11]*SPP[5] - (P[12][11]*q0)/2))/2;
-    nextP[3][3] = P[3][3] + P[0][3]*SF[4] + P[1][3]*SF[3] + P[2][3]*SF[6] + P[10][3]*SPP[4] - P[11][3]*SPP[5] + (dayCov*SQ[10])/4 + dazCov*SQ[9] - (P[12][3]*q0)/2 + SF[4]*(P[3][0] + P[0][0]*SF[4] + P[1][0]*SF[3] + P[2][0]*SF[6] + P[10][0]*SPP[4] - P[11][0]*SPP[5] - (P[12][0]*q0)/2) + SF[3]*(P[3][1] + P[0][1]*SF[4] + P[1][1]*SF[3] + P[2][1]*SF[6] + P[10][1]*SPP[4] - P[11][1]*SPP[5] - (P[12][1]*q0)/2) + SF[6]*(P[3][2] + P[0][2]*SF[4] + P[1][2]*SF[3] + P[2][2]*SF[6] + P[10][2]*SPP[4] - P[11][2]*SPP[5] - (P[12][2]*q0)/2) + SPP[4]*(P[3][10] + P[0][10]*SF[4] + P[1][10]*SF[3] + P[2][10]*SF[6] + P[10][10]*SPP[4] - P[11][10]*SPP[5] - (P[12][10]*q0)/2) - SPP[5]*(P[3][11] + P[0][11]*SF[4] + P[1][11]*SF[3] + P[2][11]*SF[6] + P[10][11]*SPP[4] - P[11][11]*SPP[5] - (P[12][11]*q0)/2) + (daxCov*sq(q2))/4 - (q0*(P[3][12] + P[0][12]*SF[4] + P[1][12]*SF[3] + P[2][12]*SF[6] + P[10][12]*SPP[4] - P[11][12]*SPP[5] - (P[12][12]*q0)/2))/2;
-    nextP[3][4] = P[3][4] + P[0][4]*SF[4] + P[1][4]*SF[3] + P[2][4]*SF[6] + P[10][4]*SPP[4] - P[11][4]*SPP[5] - (P[12][4]*q0)/2 + SF[2]*(P[3][0] + P[0][0]*SF[4] + P[1][0]*SF[3] + P[2][0]*SF[6] + P[10][0]*SPP[4] - P[11][0]*SPP[5] - (P[12][0]*q0)/2) + SF[0]*(P[3][1] + P[0][1]*SF[4] + P[1][1]*SF[3] + P[2][1]*SF[6] + P[10][1]*SPP[4] - P[11][1]*SPP[5] - (P[12][1]*q0)/2) + SPP[0]*(P[3][2] + P[0][2]*SF[4] + P[1][2]*SF[3] + P[2][2]*SF[6] + P[10][2]*SPP[4] - P[11][2]*SPP[5] - (P[12][2]*q0)/2) - SPP[2]*(P[3][3] + P[0][3]*SF[4] + P[1][3]*SF[3] + P[2][3]*SF[6] + P[10][3]*SPP[4] - P[11][3]*SPP[5] - (P[12][3]*q0)/2);
-    nextP[3][5] = P[3][5] + P[0][5]*SF[4] + P[1][5]*SF[3] + P[2][5]*SF[6] + P[10][5]*SPP[4] - P[11][5]*SPP[5] - (P[12][5]*q0)/2 + SF[1]*(P[3][0] + P[0][0]*SF[4] + P[1][0]*SF[3] + P[2][0]*SF[6] + P[10][0]*SPP[4] - P[11][0]*SPP[5] - (P[12][0]*q0)/2) + SF[0]*(P[3][2] + P[0][2]*SF[4] + P[1][2]*SF[3] + P[2][2]*SF[6] + P[10][2]*SPP[4] - P[11][2]*SPP[5] - (P[12][2]*q0)/2) + SF[2]*(P[3][3] + P[0][3]*SF[4] + P[1][3]*SF[3] + P[2][3]*SF[6] + P[10][3]*SPP[4] - P[11][3]*SPP[5] - (P[12][3]*q0)/2) - SPP[0]*(P[3][1] + P[0][1]*SF[4] + P[1][1]*SF[3] + P[2][1]*SF[6] + P[10][1]*SPP[4] - P[11][1]*SPP[5] - (P[12][1]*q0)/2);
-    nextP[3][6] = P[3][6] + P[0][6]*SF[4] + P[1][6]*SF[3] + P[2][6]*SF[6] + P[10][6]*SPP[4] - P[11][6]*SPP[5] - (P[12][6]*q0)/2 + SF[1]*(P[3][1] + P[0][1]*SF[4] + P[1][1]*SF[3] + P[2][1]*SF[6] + P[10][1]*SPP[4] - P[11][1]*SPP[5] - (P[12][1]*q0)/2) + SF[0]*(P[3][3] + P[0][3]*SF[4] + P[1][3]*SF[3] + P[2][3]*SF[6] + P[10][3]*SPP[4] - P[11][3]*SPP[5] - (P[12][3]*q0)/2) + SPP[0]*(P[3][0] + P[0][0]*SF[4] + P[1][0]*SF[3] + P[2][0]*SF[6] + P[10][0]*SPP[4] - P[11][0]*SPP[5] - (P[12][0]*q0)/2) - SPP[1]*(P[3][2] + P[0][2]*SF[4] + P[1][2]*SF[3] + P[2][2]*SF[6] + P[10][2]*SPP[4] - P[11][2]*SPP[5] - (P[12][2]*q0)/2);
-    nextP[3][7] = P[3][7] + P[0][7]*SF[4] + P[1][7]*SF[3] + P[2][7]*SF[6] + P[10][7]*SPP[4] - P[11][7]*SPP[5] - (P[12][7]*q0)/2 + dt*(P[3][4] + P[0][4]*SF[4] + P[1][4]*SF[3] + P[2][4]*SF[6] + P[10][4]*SPP[4] - P[11][4]*SPP[5] - (P[12][4]*q0)/2);
-    nextP[3][8] = P[3][8] + P[0][8]*SF[4] + P[1][8]*SF[3] + P[2][8]*SF[6] + P[10][8]*SPP[4] - P[11][8]*SPP[5] - (P[12][8]*q0)/2 + dt*(P[3][5] + P[0][5]*SF[4] + P[1][5]*SF[3] + P[2][5]*SF[6] + P[10][5]*SPP[4] - P[11][5]*SPP[5] - (P[12][5]*q0)/2);
-    nextP[3][9] = P[3][9] + P[0][9]*SF[4] + P[1][9]*SF[3] + P[2][9]*SF[6] + P[10][9]*SPP[4] - P[11][9]*SPP[5] - (P[12][9]*q0)/2 + dt*(P[3][6] + P[0][6]*SF[4] + P[1][6]*SF[3] + P[2][6]*SF[6] + P[10][6]*SPP[4] - P[11][6]*SPP[5] - (P[12][6]*q0)/2);
-    nextP[3][10] = P[3][10] + P[0][10]*SF[4] + P[1][10]*SF[3] + P[2][10]*SF[6] + P[10][10]*SPP[4] - P[11][10]*SPP[5] - (P[12][10]*q0)/2;
-    nextP[3][11] = P[3][11] + P[0][11]*SF[4] + P[1][11]*SF[3] + P[2][11]*SF[6] + P[10][11]*SPP[4] - P[11][11]*SPP[5] - (P[12][11]*q0)/2;
-    nextP[3][12] = P[3][12] + P[0][12]*SF[4] + P[1][12]*SF[3] + P[2][12]*SF[6] + P[10][12]*SPP[4] - P[11][12]*SPP[5] - (P[12][12]*q0)/2;
-    nextP[3][13] = P[3][13] + P[0][13]*SF[4] + P[1][13]*SF[3] + P[2][13]*SF[6] + P[10][13]*SPP[4] - P[11][13]*SPP[5] - (P[12][13]*q0)/2;
-    nextP[3][14] = P[3][14] + P[0][14]*SF[4] + P[1][14]*SF[3] + P[2][14]*SF[6] + P[10][14]*SPP[4] - P[11][14]*SPP[5] - (P[12][14]*q0)/2;
-    nextP[3][15] = P[3][15] + P[0][15]*SF[4] + P[1][15]*SF[3] + P[2][15]*SF[6] + P[10][15]*SPP[4] - P[11][15]*SPP[5] - (P[12][15]*q0)/2;
-    nextP[3][16] = P[3][16] + P[0][16]*SF[4] + P[1][16]*SF[3] + P[2][16]*SF[6] + P[10][16]*SPP[4] - P[11][16]*SPP[5] - (P[12][16]*q0)/2;
-    nextP[3][17] = P[3][17] + P[0][17]*SF[4] + P[1][17]*SF[3] + P[2][17]*SF[6] + P[10][17]*SPP[4] - P[11][17]*SPP[5] - (P[12][17]*q0)/2;
-    nextP[3][18] = P[3][18] + P[0][18]*SF[4] + P[1][18]*SF[3] + P[2][18]*SF[6] + P[10][18]*SPP[4] - P[11][18]*SPP[5] - (P[12][18]*q0)/2;
-    nextP[3][19] = P[3][19] + P[0][19]*SF[4] + P[1][19]*SF[3] + P[2][19]*SF[6] + P[10][19]*SPP[4] - P[11][19]*SPP[5] - (P[12][19]*q0)/2;
-    nextP[3][20] = P[3][20] + P[0][20]*SF[4] + P[1][20]*SF[3] + P[2][20]*SF[6] + P[10][20]*SPP[4] - P[11][20]*SPP[5] - (P[12][20]*q0)/2;
-    nextP[4][0] = P[4][0] + P[0][0]*SF[2] + P[1][0]*SF[0] + P[2][0]*SPP[0] - P[3][0]*SPP[2] + SF[6]*(P[4][1] + P[0][1]*SF[2] + P[1][1]*SF[0] + P[2][1]*SPP[0] - P[3][1]*SPP[2]) + SPP[7]*(P[4][2] + P[0][2]*SF[2] + P[1][2]*SF[0] + P[2][2]*SPP[0] - P[3][2]*SPP[2]) + SPP[6]*(P[4][3] + P[0][3]*SF[2] + P[1][3]*SF[0] + P[2][3]*SPP[0] - P[3][3]*SPP[2]) + SPP[5]*(P[4][10] + P[0][10]*SF[2] + P[1][10]*SF[0] + P[2][10]*SPP[0] - P[3][10]*SPP[2]) + SPP[4]*(P[4][11] + P[0][11]*SF[2] + P[1][11]*SF[0] + P[2][11]*SPP[0] - P[3][11]*SPP[2]) + SPP[3]*(P[4][12] + P[0][12]*SF[2] + P[1][12]*SF[0] + P[2][12]*SPP[0] - P[3][12]*SPP[2]);
-    nextP[4][1] = P[4][1] + P[0][1]*SF[2] + P[1][1]*SF[0] + P[2][1]*SPP[0] - P[3][1]*SPP[2] + SF[5]*(P[4][0] + P[0][0]*SF[2] + P[1][0]*SF[0] + P[2][0]*SPP[0] - P[3][0]*SPP[2]) + SF[4]*(P[4][2] + P[0][2]*SF[2] + P[1][2]*SF[0] + P[2][2]*SPP[0] - P[3][2]*SPP[2]) + SPP[7]*(P[4][3] + P[0][3]*SF[2] + P[1][3]*SF[0] + P[2][3]*SPP[0] - P[3][3]*SPP[2]) + SPP[3]*(P[4][11] + P[0][11]*SF[2] + P[1][11]*SF[0] + P[2][11]*SPP[0] - P[3][11]*SPP[2]) - SPP[4]*(P[4][12] + P[0][12]*SF[2] + P[1][12]*SF[0] + P[2][12]*SPP[0] - P[3][12]*SPP[2]) - (q0*(P[4][10] + P[0][10]*SF[2] + P[1][10]*SF[0] + P[2][10]*SPP[0] - P[3][10]*SPP[2]))/2;
-    nextP[4][2] = P[4][2] + P[0][2]*SF[2] + P[1][2]*SF[0] + P[2][2]*SPP[0] - P[3][2]*SPP[2] + SF[3]*(P[4][0] + P[0][0]*SF[2] + P[1][0]*SF[0] + P[2][0]*SPP[0] - P[3][0]*SPP[2]) + SF[5]*(P[4][3] + P[0][3]*SF[2] + P[1][3]*SF[0] + P[2][3]*SPP[0] - P[3][3]*SPP[2]) + SPP[6]*(P[4][1] + P[0][1]*SF[2] + P[1][1]*SF[0] + P[2][1]*SPP[0] - P[3][1]*SPP[2]) - SPP[3]*(P[4][10] + P[0][10]*SF[2] + P[1][10]*SF[0] + P[2][10]*SPP[0] - P[3][10]*SPP[2]) + SPP[5]*(P[4][12] + P[0][12]*SF[2] + P[1][12]*SF[0] + P[2][12]*SPP[0] - P[3][12]*SPP[2]) - (q0*(P[4][11] + P[0][11]*SF[2] + P[1][11]*SF[0] + P[2][11]*SPP[0] - P[3][11]*SPP[2]))/2;
-    nextP[4][3] = P[4][3] + P[0][3]*SF[2] + P[1][3]*SF[0] + P[2][3]*SPP[0] - P[3][3]*SPP[2] + SF[4]*(P[4][0] + P[0][0]*SF[2] + P[1][0]*SF[0] + P[2][0]*SPP[0] - P[3][0]*SPP[2]) + SF[3]*(P[4][1] + P[0][1]*SF[2] + P[1][1]*SF[0] + P[2][1]*SPP[0] - P[3][1]*SPP[2]) + SF[6]*(P[4][2] + P[0][2]*SF[2] + P[1][2]*SF[0] + P[2][2]*SPP[0] - P[3][2]*SPP[2]) + SPP[4]*(P[4][10] + P[0][10]*SF[2] + P[1][10]*SF[0] + P[2][10]*SPP[0] - P[3][10]*SPP[2]) - SPP[5]*(P[4][11] + P[0][11]*SF[2] + P[1][11]*SF[0] + P[2][11]*SPP[0] - P[3][11]*SPP[2]) - (q0*(P[4][12] + P[0][12]*SF[2] + P[1][12]*SF[0] + P[2][12]*SPP[0] - P[3][12]*SPP[2]))/2;
-    nextP[4][4] = P[4][4] + P[0][4]*SF[2] + P[1][4]*SF[0] + P[2][4]*SPP[0] - P[3][4]*SPP[2] + dvyCov*sq(SG[7] - 2*q0*q3) + dvzCov*sq(SG[6] + 2*q0*q2) + SF[2]*(P[4][0] + P[0][0]*SF[2] + P[1][0]*SF[0] + P[2][0]*SPP[0] - P[3][0]*SPP[2]) + SF[0]*(P[4][1] + P[0][1]*SF[2] + P[1][1]*SF[0] + P[2][1]*SPP[0] - P[3][1]*SPP[2]) + SPP[0]*(P[4][2] + P[0][2]*SF[2] + P[1][2]*SF[0] + P[2][2]*SPP[0] - P[3][2]*SPP[2]) - SPP[2]*(P[4][3] + P[0][3]*SF[2] + P[1][3]*SF[0] + P[2][3]*SPP[0] - P[3][3]*SPP[2]) + dvxCov*sq(SG[1] + SG[2] - SG[3] - SG[4]);
-    nextP[4][5] = P[4][5] + SQ[2] + P[0][5]*SF[2] + P[1][5]*SF[0] + P[2][5]*SPP[0] - P[3][5]*SPP[2] + SF[1]*(P[4][0] + P[0][0]*SF[2] + P[1][0]*SF[0] + P[2][0]*SPP[0] - P[3][0]*SPP[2]) + SF[0]*(P[4][2] + P[0][2]*SF[2] + P[1][2]*SF[0] + P[2][2]*SPP[0] - P[3][2]*SPP[2]) + SF[2]*(P[4][3] + P[0][3]*SF[2] + P[1][3]*SF[0] + P[2][3]*SPP[0] - P[3][3]*SPP[2]) - SPP[0]*(P[4][1] + P[0][1]*SF[2] + P[1][1]*SF[0] + P[2][1]*SPP[0] - P[3][1]*SPP[2]);
-    nextP[4][6] = P[4][6] + SQ[1] + P[0][6]*SF[2] + P[1][6]*SF[0] + P[2][6]*SPP[0] - P[3][6]*SPP[2] + SF[1]*(P[4][1] + P[0][1]*SF[2] + P[1][1]*SF[0] + P[2][1]*SPP[0] - P[3][1]*SPP[2]) + SF[0]*(P[4][3] + P[0][3]*SF[2] + P[1][3]*SF[0] + P[2][3]*SPP[0] - P[3][3]*SPP[2]) + SPP[0]*(P[4][0] + P[0][0]*SF[2] + P[1][0]*SF[0] + P[2][0]*SPP[0] - P[3][0]*SPP[2]) - SPP[1]*(P[4][2] + P[0][2]*SF[2] + P[1][2]*SF[0] + P[2][2]*SPP[0] - P[3][2]*SPP[2]);
-    nextP[4][7] = P[4][7] + P[0][7]*SF[2] + P[1][7]*SF[0] + P[2][7]*SPP[0] - P[3][7]*SPP[2] + dt*(P[4][4] + P[0][4]*SF[2] + P[1][4]*SF[0] + P[2][4]*SPP[0] - P[3][4]*SPP[2]);
-    nextP[4][8] = P[4][8] + P[0][8]*SF[2] + P[1][8]*SF[0] + P[2][8]*SPP[0] - P[3][8]*SPP[2] + dt*(P[4][5] + P[0][5]*SF[2] + P[1][5]*SF[0] + P[2][5]*SPP[0] - P[3][5]*SPP[2]);
-    nextP[4][9] = P[4][9] + P[0][9]*SF[2] + P[1][9]*SF[0] + P[2][9]*SPP[0] - P[3][9]*SPP[2] + dt*(P[4][6] + P[0][6]*SF[2] + P[1][6]*SF[0] + P[2][6]*SPP[0] - P[3][6]*SPP[2]);
-    nextP[4][10] = P[4][10] + P[0][10]*SF[2] + P[1][10]*SF[0] + P[2][10]*SPP[0] - P[3][10]*SPP[2];
-    nextP[4][11] = P[4][11] + P[0][11]*SF[2] + P[1][11]*SF[0] + P[2][11]*SPP[0] - P[3][11]*SPP[2];
-    nextP[4][12] = P[4][12] + P[0][12]*SF[2] + P[1][12]*SF[0] + P[2][12]*SPP[0] - P[3][12]*SPP[2];
-    nextP[4][13] = P[4][13] + P[0][13]*SF[2] + P[1][13]*SF[0] + P[2][13]*SPP[0] - P[3][13]*SPP[2];
-    nextP[4][14] = P[4][14] + P[0][14]*SF[2] + P[1][14]*SF[0] + P[2][14]*SPP[0] - P[3][14]*SPP[2];
-    nextP[4][15] = P[4][15] + P[0][15]*SF[2] + P[1][15]*SF[0] + P[2][15]*SPP[0] - P[3][15]*SPP[2];
-    nextP[4][16] = P[4][16] + P[0][16]*SF[2] + P[1][16]*SF[0] + P[2][16]*SPP[0] - P[3][16]*SPP[2];
-    nextP[4][17] = P[4][17] + P[0][17]*SF[2] + P[1][17]*SF[0] + P[2][17]*SPP[0] - P[3][17]*SPP[2];
-    nextP[4][18] = P[4][18] + P[0][18]*SF[2] + P[1][18]*SF[0] + P[2][18]*SPP[0] - P[3][18]*SPP[2];
-    nextP[4][19] = P[4][19] + P[0][19]*SF[2] + P[1][19]*SF[0] + P[2][19]*SPP[0] - P[3][19]*SPP[2];
-    nextP[4][20] = P[4][20] + P[0][20]*SF[2] + P[1][20]*SF[0] + P[2][20]*SPP[0] - P[3][20]*SPP[2];
-    nextP[5][0] = P[5][0] + P[0][0]*SF[1] + P[2][0]*SF[0] + P[3][0]*SF[2] - P[1][0]*SPP[0] + SF[6]*(P[5][1] + P[0][1]*SF[1] + P[2][1]*SF[0] + P[3][1]*SF[2] - P[1][1]*SPP[0]) + SPP[7]*(P[5][2] + P[0][2]*SF[1] + P[2][2]*SF[0] + P[3][2]*SF[2] - P[1][2]*SPP[0]) + SPP[6]*(P[5][3] + P[0][3]*SF[1] + P[2][3]*SF[0] + P[3][3]*SF[2] - P[1][3]*SPP[0]) + SPP[5]*(P[5][10] + P[0][10]*SF[1] + P[2][10]*SF[0] + P[3][10]*SF[2] - P[1][10]*SPP[0]) + SPP[4]*(P[5][11] + P[0][11]*SF[1] + P[2][11]*SF[0] + P[3][11]*SF[2] - P[1][11]*SPP[0]) + SPP[3]*(P[5][12] + P[0][12]*SF[1] + P[2][12]*SF[0] + P[3][12]*SF[2] - P[1][12]*SPP[0]);
-    nextP[5][1] = P[5][1] + P[0][1]*SF[1] + P[2][1]*SF[0] + P[3][1]*SF[2] - P[1][1]*SPP[0] + SF[5]*(P[5][0] + P[0][0]*SF[1] + P[2][0]*SF[0] + P[3][0]*SF[2] - P[1][0]*SPP[0]) + SF[4]*(P[5][2] + P[0][2]*SF[1] + P[2][2]*SF[0] + P[3][2]*SF[2] - P[1][2]*SPP[0]) + SPP[7]*(P[5][3] + P[0][3]*SF[1] + P[2][3]*SF[0] + P[3][3]*SF[2] - P[1][3]*SPP[0]) + SPP[3]*(P[5][11] + P[0][11]*SF[1] + P[2][11]*SF[0] + P[3][11]*SF[2] - P[1][11]*SPP[0]) - SPP[4]*(P[5][12] + P[0][12]*SF[1] + P[2][12]*SF[0] + P[3][12]*SF[2] - P[1][12]*SPP[0]) - (q0*(P[5][10] + P[0][10]*SF[1] + P[2][10]*SF[0] + P[3][10]*SF[2] - P[1][10]*SPP[0]))/2;
-    nextP[5][2] = P[5][2] + P[0][2]*SF[1] + P[2][2]*SF[0] + P[3][2]*SF[2] - P[1][2]*SPP[0] + SF[3]*(P[5][0] + P[0][0]*SF[1] + P[2][0]*SF[0] + P[3][0]*SF[2] - P[1][0]*SPP[0]) + SF[5]*(P[5][3] + P[0][3]*SF[1] + P[2][3]*SF[0] + P[3][3]*SF[2] - P[1][3]*SPP[0]) + SPP[6]*(P[5][1] + P[0][1]*SF[1] + P[2][1]*SF[0] + P[3][1]*SF[2] - P[1][1]*SPP[0]) - SPP[3]*(P[5][10] + P[0][10]*SF[1] + P[2][10]*SF[0] + P[3][10]*SF[2] - P[1][10]*SPP[0]) + SPP[5]*(P[5][12] + P[0][12]*SF[1] + P[2][12]*SF[0] + P[3][12]*SF[2] - P[1][12]*SPP[0]) - (q0*(P[5][11] + P[0][11]*SF[1] + P[2][11]*SF[0] + P[3][11]*SF[2] - P[1][11]*SPP[0]))/2;
-    nextP[5][3] = P[5][3] + P[0][3]*SF[1] + P[2][3]*SF[0] + P[3][3]*SF[2] - P[1][3]*SPP[0] + SF[4]*(P[5][0] + P[0][0]*SF[1] + P[2][0]*SF[0] + P[3][0]*SF[2] - P[1][0]*SPP[0]) + SF[3]*(P[5][1] + P[0][1]*SF[1] + P[2][1]*SF[0] + P[3][1]*SF[2] - P[1][1]*SPP[0]) + SF[6]*(P[5][2] + P[0][2]*SF[1] + P[2][2]*SF[0] + P[3][2]*SF[2] - P[1][2]*SPP[0]) + SPP[4]*(P[5][10] + P[0][10]*SF[1] + P[2][10]*SF[0] + P[3][10]*SF[2] - P[1][10]*SPP[0]) - SPP[5]*(P[5][11] + P[0][11]*SF[1] + P[2][11]*SF[0] + P[3][11]*SF[2] - P[1][11]*SPP[0]) - (q0*(P[5][12] + P[0][12]*SF[1] + P[2][12]*SF[0] + P[3][12]*SF[2] - P[1][12]*SPP[0]))/2;
-    nextP[5][4] = P[5][4] + SQ[2] + P[0][4]*SF[1] + P[2][4]*SF[0] + P[3][4]*SF[2] - P[1][4]*SPP[0] + SF[2]*(P[5][0] + P[0][0]*SF[1] + P[2][0]*SF[0] + P[3][0]*SF[2] - P[1][0]*SPP[0]) + SF[0]*(P[5][1] + P[0][1]*SF[1] + P[2][1]*SF[0] + P[3][1]*SF[2] - P[1][1]*SPP[0]) + SPP[0]*(P[5][2] + P[0][2]*SF[1] + P[2][2]*SF[0] + P[3][2]*SF[2] - P[1][2]*SPP[0]) - SPP[2]*(P[5][3] + P[0][3]*SF[1] + P[2][3]*SF[0] + P[3][3]*SF[2] - P[1][3]*SPP[0]);
-    nextP[5][5] = P[5][5] + P[0][5]*SF[1] + P[2][5]*SF[0] + P[3][5]*SF[2] - P[1][5]*SPP[0] + dvxCov*sq(SG[7] + 2*q0*q3) + dvzCov*sq(SG[5] - 2*q0*q1) + SF[1]*(P[5][0] + P[0][0]*SF[1] + P[2][0]*SF[0] + P[3][0]*SF[2] - P[1][0]*SPP[0]) + SF[0]*(P[5][2] + P[0][2]*SF[1] + P[2][2]*SF[0] + P[3][2]*SF[2] - P[1][2]*SPP[0]) + SF[2]*(P[5][3] + P[0][3]*SF[1] + P[2][3]*SF[0] + P[3][3]*SF[2] - P[1][3]*SPP[0]) - SPP[0]*(P[5][1] + P[0][1]*SF[1] + P[2][1]*SF[0] + P[3][1]*SF[2] - P[1][1]*SPP[0]) + dvyCov*sq(SG[1] - SG[2] + SG[3] - SG[4]);
-    nextP[5][6] = P[5][6] + SQ[0] + P[0][6]*SF[1] + P[2][6]*SF[0] + P[3][6]*SF[2] - P[1][6]*SPP[0] + SF[1]*(P[5][1] + P[0][1]*SF[1] + P[2][1]*SF[0] + P[3][1]*SF[2] - P[1][1]*SPP[0]) + SF[0]*(P[5][3] + P[0][3]*SF[1] + P[2][3]*SF[0] + P[3][3]*SF[2] - P[1][3]*SPP[0]) + SPP[0]*(P[5][0] + P[0][0]*SF[1] + P[2][0]*SF[0] + P[3][0]*SF[2] - P[1][0]*SPP[0]) - SPP[1]*(P[5][2] + P[0][2]*SF[1] + P[2][2]*SF[0] + P[3][2]*SF[2] - P[1][2]*SPP[0]);
-    nextP[5][7] = P[5][7] + P[0][7]*SF[1] + P[2][7]*SF[0] + P[3][7]*SF[2] - P[1][7]*SPP[0] + dt*(P[5][4] + P[0][4]*SF[1] + P[2][4]*SF[0] + P[3][4]*SF[2] - P[1][4]*SPP[0]);
-    nextP[5][8] = P[5][8] + P[0][8]*SF[1] + P[2][8]*SF[0] + P[3][8]*SF[2] - P[1][8]*SPP[0] + dt*(P[5][5] + P[0][5]*SF[1] + P[2][5]*SF[0] + P[3][5]*SF[2] - P[1][5]*SPP[0]);
-    nextP[5][9] = P[5][9] + P[0][9]*SF[1] + P[2][9]*SF[0] + P[3][9]*SF[2] - P[1][9]*SPP[0] + dt*(P[5][6] + P[0][6]*SF[1] + P[2][6]*SF[0] + P[3][6]*SF[2] - P[1][6]*SPP[0]);
-    nextP[5][10] = P[5][10] + P[0][10]*SF[1] + P[2][10]*SF[0] + P[3][10]*SF[2] - P[1][10]*SPP[0];
-    nextP[5][11] = P[5][11] + P[0][11]*SF[1] + P[2][11]*SF[0] + P[3][11]*SF[2] - P[1][11]*SPP[0];
-    nextP[5][12] = P[5][12] + P[0][12]*SF[1] + P[2][12]*SF[0] + P[3][12]*SF[2] - P[1][12]*SPP[0];
-    nextP[5][13] = P[5][13] + P[0][13]*SF[1] + P[2][13]*SF[0] + P[3][13]*SF[2] - P[1][13]*SPP[0];
-    nextP[5][14] = P[5][14] + P[0][14]*SF[1] + P[2][14]*SF[0] + P[3][14]*SF[2] - P[1][14]*SPP[0];
-    nextP[5][15] = P[5][15] + P[0][15]*SF[1] + P[2][15]*SF[0] + P[3][15]*SF[2] - P[1][15]*SPP[0];
-    nextP[5][16] = P[5][16] + P[0][16]*SF[1] + P[2][16]*SF[0] + P[3][16]*SF[2] - P[1][16]*SPP[0];
-    nextP[5][17] = P[5][17] + P[0][17]*SF[1] + P[2][17]*SF[0] + P[3][17]*SF[2] - P[1][17]*SPP[0];
-    nextP[5][18] = P[5][18] + P[0][18]*SF[1] + P[2][18]*SF[0] + P[3][18]*SF[2] - P[1][18]*SPP[0];
-    nextP[5][19] = P[5][19] + P[0][19]*SF[1] + P[2][19]*SF[0] + P[3][19]*SF[2] - P[1][19]*SPP[0];
-    nextP[5][20] = P[5][20] + P[0][20]*SF[1] + P[2][20]*SF[0] + P[3][20]*SF[2] - P[1][20]*SPP[0];
-    nextP[6][0] = P[6][0] + P[1][0]*SF[1] + P[3][0]*SF[0] + P[0][0]*SPP[0] - P[2][0]*SPP[1] + SF[6]*(P[6][1] + P[1][1]*SF[1] + P[3][1]*SF[0] + P[0][1]*SPP[0] - P[2][1]*SPP[1]) + SPP[7]*(P[6][2] + P[1][2]*SF[1] + P[3][2]*SF[0] + P[0][2]*SPP[0] - P[2][2]*SPP[1]) + SPP[6]*(P[6][3] + P[1][3]*SF[1] + P[3][3]*SF[0] + P[0][3]*SPP[0] - P[2][3]*SPP[1]) + SPP[5]*(P[6][10] + P[1][10]*SF[1] + P[3][10]*SF[0] + P[0][10]*SPP[0] - P[2][10]*SPP[1]) + SPP[4]*(P[6][11] + P[1][11]*SF[1] + P[3][11]*SF[0] + P[0][11]*SPP[0] - P[2][11]*SPP[1]) + SPP[3]*(P[6][12] + P[1][12]*SF[1] + P[3][12]*SF[0] + P[0][12]*SPP[0] - P[2][12]*SPP[1]);
-    nextP[6][1] = P[6][1] + P[1][1]*SF[1] + P[3][1]*SF[0] + P[0][1]*SPP[0] - P[2][1]*SPP[1] + SF[5]*(P[6][0] + P[1][0]*SF[1] + P[3][0]*SF[0] + P[0][0]*SPP[0] - P[2][0]*SPP[1]) + SF[4]*(P[6][2] + P[1][2]*SF[1] + P[3][2]*SF[0] + P[0][2]*SPP[0] - P[2][2]*SPP[1]) + SPP[7]*(P[6][3] + P[1][3]*SF[1] + P[3][3]*SF[0] + P[0][3]*SPP[0] - P[2][3]*SPP[1]) + SPP[3]*(P[6][11] + P[1][11]*SF[1] + P[3][11]*SF[0] + P[0][11]*SPP[0] - P[2][11]*SPP[1]) - SPP[4]*(P[6][12] + P[1][12]*SF[1] + P[3][12]*SF[0] + P[0][12]*SPP[0] - P[2][12]*SPP[1]) - (q0*(P[6][10] + P[1][10]*SF[1] + P[3][10]*SF[0] + P[0][10]*SPP[0] - P[2][10]*SPP[1]))/2;
-    nextP[6][2] = P[6][2] + P[1][2]*SF[1] + P[3][2]*SF[0] + P[0][2]*SPP[0] - P[2][2]*SPP[1] + SF[3]*(P[6][0] + P[1][0]*SF[1] + P[3][0]*SF[0] + P[0][0]*SPP[0] - P[2][0]*SPP[1]) + SF[5]*(P[6][3] + P[1][3]*SF[1] + P[3][3]*SF[0] + P[0][3]*SPP[0] - P[2][3]*SPP[1]) + SPP[6]*(P[6][1] + P[1][1]*SF[1] + P[3][1]*SF[0] + P[0][1]*SPP[0] - P[2][1]*SPP[1]) - SPP[3]*(P[6][10] + P[1][10]*SF[1] + P[3][10]*SF[0] + P[0][10]*SPP[0] - P[2][10]*SPP[1]) + SPP[5]*(P[6][12] + P[1][12]*SF[1] + P[3][12]*SF[0] + P[0][12]*SPP[0] - P[2][12]*SPP[1]) - (q0*(P[6][11] + P[1][11]*SF[1] + P[3][11]*SF[0] + P[0][11]*SPP[0] - P[2][11]*SPP[1]))/2;
-    nextP[6][3] = P[6][3] + P[1][3]*SF[1] + P[3][3]*SF[0] + P[0][3]*SPP[0] - P[2][3]*SPP[1] + SF[4]*(P[6][0] + P[1][0]*SF[1] + P[3][0]*SF[0] + P[0][0]*SPP[0] - P[2][0]*SPP[1]) + SF[3]*(P[6][1] + P[1][1]*SF[1] + P[3][1]*SF[0] + P[0][1]*SPP[0] - P[2][1]*SPP[1]) + SF[6]*(P[6][2] + P[1][2]*SF[1] + P[3][2]*SF[0] + P[0][2]*SPP[0] - P[2][2]*SPP[1]) + SPP[4]*(P[6][10] + P[1][10]*SF[1] + P[3][10]*SF[0] + P[0][10]*SPP[0] - P[2][10]*SPP[1]) - SPP[5]*(P[6][11] + P[1][11]*SF[1] + P[3][11]*SF[0] + P[0][11]*SPP[0] - P[2][11]*SPP[1]) - (q0*(P[6][12] + P[1][12]*SF[1] + P[3][12]*SF[0] + P[0][12]*SPP[0] - P[2][12]*SPP[1]))/2;
-    nextP[6][4] = P[6][4] + SQ[1] + P[1][4]*SF[1] + P[3][4]*SF[0] + P[0][4]*SPP[0] - P[2][4]*SPP[1] + SF[2]*(P[6][0] + P[1][0]*SF[1] + P[3][0]*SF[0] + P[0][0]*SPP[0] - P[2][0]*SPP[1]) + SF[0]*(P[6][1] + P[1][1]*SF[1] + P[3][1]*SF[0] + P[0][1]*SPP[0] - P[2][1]*SPP[1]) + SPP[0]*(P[6][2] + P[1][2]*SF[1] + P[3][2]*SF[0] + P[0][2]*SPP[0] - P[2][2]*SPP[1]) - SPP[2]*(P[6][3] + P[1][3]*SF[1] + P[3][3]*SF[0] + P[0][3]*SPP[0] - P[2][3]*SPP[1]);
-    nextP[6][5] = P[6][5] + SQ[0] + P[1][5]*SF[1] + P[3][5]*SF[0] + P[0][5]*SPP[0] - P[2][5]*SPP[1] + SF[1]*(P[6][0] + P[1][0]*SF[1] + P[3][0]*SF[0] + P[0][0]*SPP[0] - P[2][0]*SPP[1]) + SF[0]*(P[6][2] + P[1][2]*SF[1] + P[3][2]*SF[0] + P[0][2]*SPP[0] - P[2][2]*SPP[1]) + SF[2]*(P[6][3] + P[1][3]*SF[1] + P[3][3]*SF[0] + P[0][3]*SPP[0] - P[2][3]*SPP[1]) - SPP[0]*(P[6][1] + P[1][1]*SF[1] + P[3][1]*SF[0] + P[0][1]*SPP[0] - P[2][1]*SPP[1]);
-    nextP[6][6] = P[6][6] + P[1][6]*SF[1] + P[3][6]*SF[0] + P[0][6]*SPP[0] - P[2][6]*SPP[1] + dvxCov*sq(SG[6] - 2*q0*q2) + dvyCov*sq(SG[5] + 2*q0*q1) + SF[1]*(P[6][1] + P[1][1]*SF[1] + P[3][1]*SF[0] + P[0][1]*SPP[0] - P[2][1]*SPP[1]) + SF[0]*(P[6][3] + P[1][3]*SF[1] + P[3][3]*SF[0] + P[0][3]*SPP[0] - P[2][3]*SPP[1]) + SPP[0]*(P[6][0] + P[1][0]*SF[1] + P[3][0]*SF[0] + P[0][0]*SPP[0] - P[2][0]*SPP[1]) - SPP[1]*(P[6][2] + P[1][2]*SF[1] + P[3][2]*SF[0] + P[0][2]*SPP[0] - P[2][2]*SPP[1]) + dvzCov*sq(SG[1] - SG[2] - SG[3] + SG[4]);
-    nextP[6][7] = P[6][7] + P[1][7]*SF[1] + P[3][7]*SF[0] + P[0][7]*SPP[0] - P[2][7]*SPP[1] + dt*(P[6][4] + P[1][4]*SF[1] + P[3][4]*SF[0] + P[0][4]*SPP[0] - P[2][4]*SPP[1]);
-    nextP[6][8] = P[6][8] + P[1][8]*SF[1] + P[3][8]*SF[0] + P[0][8]*SPP[0] - P[2][8]*SPP[1] + dt*(P[6][5] + P[1][5]*SF[1] + P[3][5]*SF[0] + P[0][5]*SPP[0] - P[2][5]*SPP[1]);
-    nextP[6][9] = P[6][9] + P[1][9]*SF[1] + P[3][9]*SF[0] + P[0][9]*SPP[0] - P[2][9]*SPP[1] + dt*(P[6][6] + P[1][6]*SF[1] + P[3][6]*SF[0] + P[0][6]*SPP[0] - P[2][6]*SPP[1]);
-    nextP[6][10] = P[6][10] + P[1][10]*SF[1] + P[3][10]*SF[0] + P[0][10]*SPP[0] - P[2][10]*SPP[1];
-    nextP[6][11] = P[6][11] + P[1][11]*SF[1] + P[3][11]*SF[0] + P[0][11]*SPP[0] - P[2][11]*SPP[1];
-    nextP[6][12] = P[6][12] + P[1][12]*SF[1] + P[3][12]*SF[0] + P[0][12]*SPP[0] - P[2][12]*SPP[1];
-    nextP[6][13] = P[6][13] + P[1][13]*SF[1] + P[3][13]*SF[0] + P[0][13]*SPP[0] - P[2][13]*SPP[1];
-    nextP[6][14] = P[6][14] + P[1][14]*SF[1] + P[3][14]*SF[0] + P[0][14]*SPP[0] - P[2][14]*SPP[1];
-    nextP[6][15] = P[6][15] + P[1][15]*SF[1] + P[3][15]*SF[0] + P[0][15]*SPP[0] - P[2][15]*SPP[1];
-    nextP[6][16] = P[6][16] + P[1][16]*SF[1] + P[3][16]*SF[0] + P[0][16]*SPP[0] - P[2][16]*SPP[1];
-    nextP[6][17] = P[6][17] + P[1][17]*SF[1] + P[3][17]*SF[0] + P[0][17]*SPP[0] - P[2][17]*SPP[1];
-    nextP[6][18] = P[6][18] + P[1][18]*SF[1] + P[3][18]*SF[0] + P[0][18]*SPP[0] - P[2][18]*SPP[1];
-    nextP[6][19] = P[6][19] + P[1][19]*SF[1] + P[3][19]*SF[0] + P[0][19]*SPP[0] - P[2][19]*SPP[1];
-    nextP[6][20] = P[6][20] + P[1][20]*SF[1] + P[3][20]*SF[0] + P[0][20]*SPP[0] - P[2][20]*SPP[1];
-    nextP[7][0] = P[7][0] + P[4][0]*dt + SF[6]*(P[7][1] + P[4][1]*dt) + SPP[7]*(P[7][2] + P[4][2]*dt) + SPP[6]*(P[7][3] + P[4][3]*dt) + SPP[5]*(P[7][10] + P[4][10]*dt) + SPP[4]*(P[7][11] + P[4][11]*dt) + SPP[3]*(P[7][12] + P[4][12]*dt);
-    nextP[7][1] = P[7][1] + P[4][1]*dt + SF[5]*(P[7][0] + P[4][0]*dt) + SF[4]*(P[7][2] + P[4][2]*dt) + SPP[7]*(P[7][3] + P[4][3]*dt) + SPP[3]*(P[7][11] + P[4][11]*dt) - SPP[4]*(P[7][12] + P[4][12]*dt) - (q0*(P[7][10] + P[4][10]*dt))/2;
-    nextP[7][2] = P[7][2] + P[4][2]*dt + SF[3]*(P[7][0] + P[4][0]*dt) + SF[5]*(P[7][3] + P[4][3]*dt) + SPP[6]*(P[7][1] + P[4][1]*dt) - SPP[3]*(P[7][10] + P[4][10]*dt) + SPP[5]*(P[7][12] + P[4][12]*dt) - (q0*(P[7][11] + P[4][11]*dt))/2;
-    nextP[7][3] = P[7][3] + P[4][3]*dt + SF[4]*(P[7][0] + P[4][0]*dt) + SF[3]*(P[7][1] + P[4][1]*dt) + SF[6]*(P[7][2] + P[4][2]*dt) + SPP[4]*(P[7][10] + P[4][10]*dt) - SPP[5]*(P[7][11] + P[4][11]*dt) - (q0*(P[7][12] + P[4][12]*dt))/2;
-    nextP[7][4] = P[7][4] + P[4][4]*dt + SF[0]*(P[7][1] + P[4][1]*dt) + SF[2]*(P[7][0] + P[4][0]*dt) + SPP[0]*(P[7][2] + P[4][2]*dt) - SPP[2]*(P[7][3] + P[4][3]*dt);
-    nextP[7][5] = P[7][5] + P[4][5]*dt + SF[1]*(P[7][0] + P[4][0]*dt) + SF[0]*(P[7][2] + P[4][2]*dt) + SF[2]*(P[7][3] + P[4][3]*dt) - SPP[0]*(P[7][1] + P[4][1]*dt);
-    nextP[7][6] = P[7][6] + P[4][6]*dt + SF[1]*(P[7][1] + P[4][1]*dt) + SF[0]*(P[7][3] + P[4][3]*dt) + SPP[0]*(P[7][0] + P[4][0]*dt) - SPP[1]*(P[7][2] + P[4][2]*dt);
-    nextP[7][7] = P[7][7] + P[4][7]*dt + dt*(P[7][4] + P[4][4]*dt);
-    nextP[7][8] = P[7][8] + P[4][8]*dt + dt*(P[7][5] + P[4][5]*dt);
-    nextP[7][9] = P[7][9] + P[4][9]*dt + dt*(P[7][6] + P[4][6]*dt);
-    nextP[7][10] = P[7][10] + P[4][10]*dt;
-    nextP[7][11] = P[7][11] + P[4][11]*dt;
-    nextP[7][12] = P[7][12] + P[4][12]*dt;
-    nextP[7][13] = P[7][13] + P[4][13]*dt;
-    nextP[7][14] = P[7][14] + P[4][14]*dt;
-    nextP[7][15] = P[7][15] + P[4][15]*dt;
-    nextP[7][16] = P[7][16] + P[4][16]*dt;
-    nextP[7][17] = P[7][17] + P[4][17]*dt;
-    nextP[7][18] = P[7][18] + P[4][18]*dt;
-    nextP[7][19] = P[7][19] + P[4][19]*dt;
-    nextP[7][20] = P[7][20] + P[4][20]*dt;
-    nextP[8][0] = P[8][0] + P[5][0]*dt + SF[6]*(P[8][1] + P[5][1]*dt) + SPP[7]*(P[8][2] + P[5][2]*dt) + SPP[6]*(P[8][3] + P[5][3]*dt) + SPP[5]*(P[8][10] + P[5][10]*dt) + SPP[4]*(P[8][11] + P[5][11]*dt) + SPP[3]*(P[8][12] + P[5][12]*dt);
-    nextP[8][1] = P[8][1] + P[5][1]*dt + SF[5]*(P[8][0] + P[5][0]*dt) + SF[4]*(P[8][2] + P[5][2]*dt) + SPP[7]*(P[8][3] + P[5][3]*dt) + SPP[3]*(P[8][11] + P[5][11]*dt) - SPP[4]*(P[8][12] + P[5][12]*dt) - (q0*(P[8][10] + P[5][10]*dt))/2;
-    nextP[8][2] = P[8][2] + P[5][2]*dt + SF[3]*(P[8][0] + P[5][0]*dt) + SF[5]*(P[8][3] + P[5][3]*dt) + SPP[6]*(P[8][1] + P[5][1]*dt) - SPP[3]*(P[8][10] + P[5][10]*dt) + SPP[5]*(P[8][12] + P[5][12]*dt) - (q0*(P[8][11] + P[5][11]*dt))/2;
-    nextP[8][3] = P[8][3] + P[5][3]*dt + SF[4]*(P[8][0] + P[5][0]*dt) + SF[3]*(P[8][1] + P[5][1]*dt) + SF[6]*(P[8][2] + P[5][2]*dt) + SPP[4]*(P[8][10] + P[5][10]*dt) - SPP[5]*(P[8][11] + P[5][11]*dt) - (q0*(P[8][12] + P[5][12]*dt))/2;
-    nextP[8][4] = P[8][4] + P[5][4]*dt + SF[0]*(P[8][1] + P[5][1]*dt) + SF[2]*(P[8][0] + P[5][0]*dt) + SPP[0]*(P[8][2] + P[5][2]*dt) - SPP[2]*(P[8][3] + P[5][3]*dt);
-    nextP[8][5] = P[8][5] + P[5][5]*dt + SF[1]*(P[8][0] + P[5][0]*dt) + SF[0]*(P[8][2] + P[5][2]*dt) + SF[2]*(P[8][3] + P[5][3]*dt) - SPP[0]*(P[8][1] + P[5][1]*dt);
-    nextP[8][6] = P[8][6] + P[5][6]*dt + SF[1]*(P[8][1] + P[5][1]*dt) + SF[0]*(P[8][3] + P[5][3]*dt) + SPP[0]*(P[8][0] + P[5][0]*dt) - SPP[1]*(P[8][2] + P[5][2]*dt);
-    nextP[8][7] = P[8][7] + P[5][7]*dt + dt*(P[8][4] + P[5][4]*dt);
-    nextP[8][8] = P[8][8] + P[5][8]*dt + dt*(P[8][5] + P[5][5]*dt);
-    nextP[8][9] = P[8][9] + P[5][9]*dt + dt*(P[8][6] + P[5][6]*dt);
-    nextP[8][10] = P[8][10] + P[5][10]*dt;
-    nextP[8][11] = P[8][11] + P[5][11]*dt;
-    nextP[8][12] = P[8][12] + P[5][12]*dt;
-    nextP[8][13] = P[8][13] + P[5][13]*dt;
-    nextP[8][14] = P[8][14] + P[5][14]*dt;
-    nextP[8][15] = P[8][15] + P[5][15]*dt;
-    nextP[8][16] = P[8][16] + P[5][16]*dt;
-    nextP[8][17] = P[8][17] + P[5][17]*dt;
-    nextP[8][18] = P[8][18] + P[5][18]*dt;
-    nextP[8][19] = P[8][19] + P[5][19]*dt;
-    nextP[8][20] = P[8][20] + P[5][20]*dt;
-    nextP[9][0] = P[9][0] + P[6][0]*dt + SF[6]*(P[9][1] + P[6][1]*dt) + SPP[7]*(P[9][2] + P[6][2]*dt) + SPP[6]*(P[9][3] + P[6][3]*dt) + SPP[5]*(P[9][10] + P[6][10]*dt) + SPP[4]*(P[9][11] + P[6][11]*dt) + SPP[3]*(P[9][12] + P[6][12]*dt);
-    nextP[9][1] = P[9][1] + P[6][1]*dt + SF[5]*(P[9][0] + P[6][0]*dt) + SF[4]*(P[9][2] + P[6][2]*dt) + SPP[7]*(P[9][3] + P[6][3]*dt) + SPP[3]*(P[9][11] + P[6][11]*dt) - SPP[4]*(P[9][12] + P[6][12]*dt) - (q0*(P[9][10] + P[6][10]*dt))/2;
-    nextP[9][2] = P[9][2] + P[6][2]*dt + SF[3]*(P[9][0] + P[6][0]*dt) + SF[5]*(P[9][3] + P[6][3]*dt) + SPP[6]*(P[9][1] + P[6][1]*dt) - SPP[3]*(P[9][10] + P[6][10]*dt) + SPP[5]*(P[9][12] + P[6][12]*dt) - (q0*(P[9][11] + P[6][11]*dt))/2;
-    nextP[9][3] = P[9][3] + P[6][3]*dt + SF[4]*(P[9][0] + P[6][0]*dt) + SF[3]*(P[9][1] + P[6][1]*dt) + SF[6]*(P[9][2] + P[6][2]*dt) + SPP[4]*(P[9][10] + P[6][10]*dt) - SPP[5]*(P[9][11] + P[6][11]*dt) - (q0*(P[9][12] + P[6][12]*dt))/2;
-    nextP[9][4] = P[9][4] + P[6][4]*dt + SF[0]*(P[9][1] + P[6][1]*dt) + SF[2]*(P[9][0] + P[6][0]*dt) + SPP[0]*(P[9][2] + P[6][2]*dt) - SPP[2]*(P[9][3] + P[6][3]*dt);
-    nextP[9][5] = P[9][5] + P[6][5]*dt + SF[1]*(P[9][0] + P[6][0]*dt) + SF[0]*(P[9][2] + P[6][2]*dt) + SF[2]*(P[9][3] + P[6][3]*dt) - SPP[0]*(P[9][1] + P[6][1]*dt);
-    nextP[9][6] = P[9][6] + P[6][6]*dt + SF[1]*(P[9][1] + P[6][1]*dt) + SF[0]*(P[9][3] + P[6][3]*dt) + SPP[0]*(P[9][0] + P[6][0]*dt) - SPP[1]*(P[9][2] + P[6][2]*dt);
-    nextP[9][7] = P[9][7] + P[6][7]*dt + dt*(P[9][4] + P[6][4]*dt);
-    nextP[9][8] = P[9][8] + P[6][8]*dt + dt*(P[9][5] + P[6][5]*dt);
-    nextP[9][9] = P[9][9] + P[6][9]*dt + dt*(P[9][6] + P[6][6]*dt);
-    nextP[9][10] = P[9][10] + P[6][10]*dt;
-    nextP[9][11] = P[9][11] + P[6][11]*dt;
-    nextP[9][12] = P[9][12] + P[6][12]*dt;
-    nextP[9][13] = P[9][13] + P[6][13]*dt;
-    nextP[9][14] = P[9][14] + P[6][14]*dt;
-    nextP[9][15] = P[9][15] + P[6][15]*dt;
-    nextP[9][16] = P[9][16] + P[6][16]*dt;
-    nextP[9][17] = P[9][17] + P[6][17]*dt;
-    nextP[9][18] = P[9][18] + P[6][18]*dt;
-    nextP[9][19] = P[9][19] + P[6][19]*dt;
-    nextP[9][20] = P[9][20] + P[6][20]*dt;
-    nextP[10][0] = P[10][0] + P[10][1]*SF[6] + P[10][2]*SPP[7] + P[10][3]*SPP[6] + P[10][10]*SPP[5] + P[10][11]*SPP[4] + P[10][12]*SPP[3];
-    nextP[10][1] = P[10][1] + P[10][0]*SF[5] + P[10][2]*SF[4] + P[10][3]*SPP[7] + P[10][11]*SPP[3] - P[10][12]*SPP[4] - (P[10][10]*q0)/2;
-    nextP[10][2] = P[10][2] + P[10][0]*SF[3] + P[10][3]*SF[5] + P[10][1]*SPP[6] - P[10][10]*SPP[3] + P[10][12]*SPP[5] - (P[10][11]*q0)/2;
-    nextP[10][3] = P[10][3] + P[10][0]*SF[4] + P[10][1]*SF[3] + P[10][2]*SF[6] + P[10][10]*SPP[4] - P[10][11]*SPP[5] - (P[10][12]*q0)/2;
-    nextP[10][4] = P[10][4] + P[10][1]*SF[0] + P[10][0]*SF[2] + P[10][2]*SPP[0] - P[10][3]*SPP[2];
-    nextP[10][5] = P[10][5] + P[10][0]*SF[1] + P[10][2]*SF[0] + P[10][3]*SF[2] - P[10][1]*SPP[0];
-    nextP[10][6] = P[10][6] + P[10][1]*SF[1] + P[10][3]*SF[0] + P[10][0]*SPP[0] - P[10][2]*SPP[1];
-    nextP[10][7] = P[10][7] + P[10][4]*dt;
-    nextP[10][8] = P[10][8] + P[10][5]*dt;
-    nextP[10][9] = P[10][9] + P[10][6]*dt;
-    nextP[10][10] = P[10][10];
-    nextP[10][11] = P[10][11];
-    nextP[10][12] = P[10][12];
-    nextP[10][13] = P[10][13];
-    nextP[10][14] = P[10][14];
-    nextP[10][15] = P[10][15];
-    nextP[10][16] = P[10][16];
-    nextP[10][17] = P[10][17];
-    nextP[10][18] = P[10][18];
-    nextP[10][19] = P[10][19];
-    nextP[10][20] = P[10][20];
-    nextP[11][0] = P[11][0] + P[11][1]*SF[6] + P[11][2]*SPP[7] + P[11][3]*SPP[6] + P[11][10]*SPP[5] + P[11][11]*SPP[4] + P[11][12]*SPP[3];
-    nextP[11][1] = P[11][1] + P[11][0]*SF[5] + P[11][2]*SF[4] + P[11][3]*SPP[7] + P[11][11]*SPP[3] - P[11][12]*SPP[4] - (P[11][10]*q0)/2;
-    nextP[11][2] = P[11][2] + P[11][0]*SF[3] + P[11][3]*SF[5] + P[11][1]*SPP[6] - P[11][10]*SPP[3] + P[11][12]*SPP[5] - (P[11][11]*q0)/2;
-    nextP[11][3] = P[11][3] + P[11][0]*SF[4] + P[11][1]*SF[3] + P[11][2]*SF[6] + P[11][10]*SPP[4] - P[11][11]*SPP[5] - (P[11][12]*q0)/2;
-    nextP[11][4] = P[11][4] + P[11][1]*SF[0] + P[11][0]*SF[2] + P[11][2]*SPP[0] - P[11][3]*SPP[2];
-    nextP[11][5] = P[11][5] + P[11][0]*SF[1] + P[11][2]*SF[0] + P[11][3]*SF[2] - P[11][1]*SPP[0];
-    nextP[11][6] = P[11][6] + P[11][1]*SF[1] + P[11][3]*SF[0] + P[11][0]*SPP[0] - P[11][2]*SPP[1];
-    nextP[11][7] = P[11][7] + P[11][4]*dt;
-    nextP[11][8] = P[11][8] + P[11][5]*dt;
-    nextP[11][9] = P[11][9] + P[11][6]*dt;
-    nextP[11][10] = P[11][10];
-    nextP[11][11] = P[11][11];
-    nextP[11][12] = P[11][12];
-    nextP[11][13] = P[11][13];
-    nextP[11][14] = P[11][14];
-    nextP[11][15] = P[11][15];
-    nextP[11][16] = P[11][16];
-    nextP[11][17] = P[11][17];
-    nextP[11][18] = P[11][18];
-    nextP[11][19] = P[11][19];
-    nextP[11][20] = P[11][20];
-    nextP[12][0] = P[12][0] + P[12][1]*SF[6] + P[12][2]*SPP[7] + P[12][3]*SPP[6] + P[12][10]*SPP[5] + P[12][11]*SPP[4] + P[12][12]*SPP[3];
-    nextP[12][1] = P[12][1] + P[12][0]*SF[5] + P[12][2]*SF[4] + P[12][3]*SPP[7] + P[12][11]*SPP[3] - P[12][12]*SPP[4] - (P[12][10]*q0)/2;
-    nextP[12][2] = P[12][2] + P[12][0]*SF[3] + P[12][3]*SF[5] + P[12][1]*SPP[6] - P[12][10]*SPP[3] + P[12][12]*SPP[5] - (P[12][11]*q0)/2;
-    nextP[12][3] = P[12][3] + P[12][0]*SF[4] + P[12][1]*SF[3] + P[12][2]*SF[6] + P[12][10]*SPP[4] - P[12][11]*SPP[5] - (P[12][12]*q0)/2;
-    nextP[12][4] = P[12][4] + P[12][1]*SF[0] + P[12][0]*SF[2] + P[12][2]*SPP[0] - P[12][3]*SPP[2];
-    nextP[12][5] = P[12][5] + P[12][0]*SF[1] + P[12][2]*SF[0] + P[12][3]*SF[2] - P[12][1]*SPP[0];
-    nextP[12][6] = P[12][6] + P[12][1]*SF[1] + P[12][3]*SF[0] + P[12][0]*SPP[0] - P[12][2]*SPP[1];
-    nextP[12][7] = P[12][7] + P[12][4]*dt;
-    nextP[12][8] = P[12][8] + P[12][5]*dt;
-    nextP[12][9] = P[12][9] + P[12][6]*dt;
-    nextP[12][10] = P[12][10];
-    nextP[12][11] = P[12][11];
-    nextP[12][12] = P[12][12];
-    nextP[12][13] = P[12][13];
-    nextP[12][14] = P[12][14];
-    nextP[12][15] = P[12][15];
-    nextP[12][16] = P[12][16];
-    nextP[12][17] = P[12][17];
-    nextP[12][18] = P[12][18];
-    nextP[12][19] = P[12][19];
-    nextP[12][20] = P[12][20];
-    nextP[13][0] = P[13][0] + P[13][1]*SF[6] + P[13][2]*SPP[7] + P[13][3]*SPP[6] + P[13][10]*SPP[5] + P[13][11]*SPP[4] + P[13][12]*SPP[3];
-    nextP[13][1] = P[13][1] + P[13][0]*SF[5] + P[13][2]*SF[4] + P[13][3]*SPP[7] + P[13][11]*SPP[3] - P[13][12]*SPP[4] - (P[13][10]*q0)/2;
-    nextP[13][2] = P[13][2] + P[13][0]*SF[3] + P[13][3]*SF[5] + P[13][1]*SPP[6] - P[13][10]*SPP[3] + P[13][12]*SPP[5] - (P[13][11]*q0)/2;
-    nextP[13][3] = P[13][3] + P[13][0]*SF[4] + P[13][1]*SF[3] + P[13][2]*SF[6] + P[13][10]*SPP[4] - P[13][11]*SPP[5] - (P[13][12]*q0)/2;
-    nextP[13][4] = P[13][4] + P[13][1]*SF[0] + P[13][0]*SF[2] + P[13][2]*SPP[0] - P[13][3]*SPP[2];
-    nextP[13][5] = P[13][5] + P[13][0]*SF[1] + P[13][2]*SF[0] + P[13][3]*SF[2] - P[13][1]*SPP[0];
-    nextP[13][6] = P[13][6] + P[13][1]*SF[1] + P[13][3]*SF[0] + P[13][0]*SPP[0] - P[13][2]*SPP[1];
-    nextP[13][7] = P[13][7] + P[13][4]*dt;
-    nextP[13][8] = P[13][8] + P[13][5]*dt;
-    nextP[13][9] = P[13][9] + P[13][6]*dt;
-    nextP[13][10] = P[13][10];
-    nextP[13][11] = P[13][11];
-    nextP[13][12] = P[13][12];
-    nextP[13][13] = P[13][13];
-    nextP[13][14] = P[13][14];
-    nextP[13][15] = P[13][15];
-    nextP[13][16] = P[13][16];
-    nextP[13][17] = P[13][17];
-    nextP[13][18] = P[13][18];
-    nextP[13][19] = P[13][19];
-    nextP[13][20] = P[13][20];
-    nextP[14][0] = P[14][0] + P[14][1]*SF[6] + P[14][2]*SPP[7] + P[14][3]*SPP[6] + P[14][10]*SPP[5] + P[14][11]*SPP[4] + P[14][12]*SPP[3];
-    nextP[14][1] = P[14][1] + P[14][0]*SF[5] + P[14][2]*SF[4] + P[14][3]*SPP[7] + P[14][11]*SPP[3] - P[14][12]*SPP[4] - (P[14][10]*q0)/2;
-    nextP[14][2] = P[14][2] + P[14][0]*SF[3] + P[14][3]*SF[5] + P[14][1]*SPP[6] - P[14][10]*SPP[3] + P[14][12]*SPP[5] - (P[14][11]*q0)/2;
-    nextP[14][3] = P[14][3] + P[14][0]*SF[4] + P[14][1]*SF[3] + P[14][2]*SF[6] + P[14][10]*SPP[4] - P[14][11]*SPP[5] - (P[14][12]*q0)/2;
-    nextP[14][4] = P[14][4] + P[14][1]*SF[0] + P[14][0]*SF[2] + P[14][2]*SPP[0] - P[14][3]*SPP[2];
-    nextP[14][5] = P[14][5] + P[14][0]*SF[1] + P[14][2]*SF[0] + P[14][3]*SF[2] - P[14][1]*SPP[0];
-    nextP[14][6] = P[14][6] + P[14][1]*SF[1] + P[14][3]*SF[0] + P[14][0]*SPP[0] - P[14][2]*SPP[1];
-    nextP[14][7] = P[14][7] + P[14][4]*dt;
-    nextP[14][8] = P[14][8] + P[14][5]*dt;
-    nextP[14][9] = P[14][9] + P[14][6]*dt;
-    nextP[14][10] = P[14][10];
-    nextP[14][11] = P[14][11];
-    nextP[14][12] = P[14][12];
-    nextP[14][13] = P[14][13];
-    nextP[14][14] = P[14][14];
-    nextP[14][15] = P[14][15];
-    nextP[14][16] = P[14][16];
-    nextP[14][17] = P[14][17];
-    nextP[14][18] = P[14][18];
-    nextP[14][19] = P[14][19];
-    nextP[14][20] = P[14][20];
-    nextP[15][0] = P[15][0] + P[15][1]*SF[6] + P[15][2]*SPP[7] + P[15][3]*SPP[6] + P[15][10]*SPP[5] + P[15][11]*SPP[4] + P[15][12]*SPP[3];
-    nextP[15][1] = P[15][1] + P[15][0]*SF[5] + P[15][2]*SF[4] + P[15][3]*SPP[7] + P[15][11]*SPP[3] - P[15][12]*SPP[4] - (P[15][10]*q0)/2;
-    nextP[15][2] = P[15][2] + P[15][0]*SF[3] + P[15][3]*SF[5] + P[15][1]*SPP[6] - P[15][10]*SPP[3] + P[15][12]*SPP[5] - (P[15][11]*q0)/2;
-    nextP[15][3] = P[15][3] + P[15][0]*SF[4] + P[15][1]*SF[3] + P[15][2]*SF[6] + P[15][10]*SPP[4] - P[15][11]*SPP[5] - (P[15][12]*q0)/2;
-    nextP[15][4] = P[15][4] + P[15][1]*SF[0] + P[15][0]*SF[2] + P[15][2]*SPP[0] - P[15][3]*SPP[2];
-    nextP[15][5] = P[15][5] + P[15][0]*SF[1] + P[15][2]*SF[0] + P[15][3]*SF[2] - P[15][1]*SPP[0];
-    nextP[15][6] = P[15][6] + P[15][1]*SF[1] + P[15][3]*SF[0] + P[15][0]*SPP[0] - P[15][2]*SPP[1];
-    nextP[15][7] = P[15][7] + P[15][4]*dt;
-    nextP[15][8] = P[15][8] + P[15][5]*dt;
-    nextP[15][9] = P[15][9] + P[15][6]*dt;
-    nextP[15][10] = P[15][10];
-    nextP[15][11] = P[15][11];
-    nextP[15][12] = P[15][12];
-    nextP[15][13] = P[15][13];
-    nextP[15][14] = P[15][14];
-    nextP[15][15] = P[15][15];
-    nextP[15][16] = P[15][16];
-    nextP[15][17] = P[15][17];
-    nextP[15][18] = P[15][18];
-    nextP[15][19] = P[15][19];
-    nextP[15][20] = P[15][20];
-    nextP[16][0] = P[16][0] + P[16][1]*SF[6] + P[16][2]*SPP[7] + P[16][3]*SPP[6] + P[16][10]*SPP[5] + P[16][11]*SPP[4] + P[16][12]*SPP[3];
-    nextP[16][1] = P[16][1] + P[16][0]*SF[5] + P[16][2]*SF[4] + P[16][3]*SPP[7] + P[16][11]*SPP[3] - P[16][12]*SPP[4] - (P[16][10]*q0)/2;
-    nextP[16][2] = P[16][2] + P[16][0]*SF[3] + P[16][3]*SF[5] + P[16][1]*SPP[6] - P[16][10]*SPP[3] + P[16][12]*SPP[5] - (P[16][11]*q0)/2;
-    nextP[16][3] = P[16][3] + P[16][0]*SF[4] + P[16][1]*SF[3] + P[16][2]*SF[6] + P[16][10]*SPP[4] - P[16][11]*SPP[5] - (P[16][12]*q0)/2;
-    nextP[16][4] = P[16][4] + P[16][1]*SF[0] + P[16][0]*SF[2] + P[16][2]*SPP[0] - P[16][3]*SPP[2];
-    nextP[16][5] = P[16][5] + P[16][0]*SF[1] + P[16][2]*SF[0] + P[16][3]*SF[2] - P[16][1]*SPP[0];
-    nextP[16][6] = P[16][6] + P[16][1]*SF[1] + P[16][3]*SF[0] + P[16][0]*SPP[0] - P[16][2]*SPP[1];
-    nextP[16][7] = P[16][7] + P[16][4]*dt;
-    nextP[16][8] = P[16][8] + P[16][5]*dt;
-    nextP[16][9] = P[16][9] + P[16][6]*dt;
-    nextP[16][10] = P[16][10];
-    nextP[16][11] = P[16][11];
-    nextP[16][12] = P[16][12];
-    nextP[16][13] = P[16][13];
-    nextP[16][14] = P[16][14];
-    nextP[16][15] = P[16][15];
-    nextP[16][16] = P[16][16];
-    nextP[16][17] = P[16][17];
-    nextP[16][18] = P[16][18];
-    nextP[16][19] = P[16][19];
-    nextP[16][20] = P[16][20];
-    nextP[17][0] = P[17][0] + P[17][1]*SF[6] + P[17][2]*SPP[7] + P[17][3]*SPP[6] + P[17][10]*SPP[5] + P[17][11]*SPP[4] + P[17][12]*SPP[3];
-    nextP[17][1] = P[17][1] + P[17][0]*SF[5] + P[17][2]*SF[4] + P[17][3]*SPP[7] + P[17][11]*SPP[3] - P[17][12]*SPP[4] - (P[17][10]*q0)/2;
-    nextP[17][2] = P[17][2] + P[17][0]*SF[3] + P[17][3]*SF[5] + P[17][1]*SPP[6] - P[17][10]*SPP[3] + P[17][12]*SPP[5] - (P[17][11]*q0)/2;
-    nextP[17][3] = P[17][3] + P[17][0]*SF[4] + P[17][1]*SF[3] + P[17][2]*SF[6] + P[17][10]*SPP[4] - P[17][11]*SPP[5] - (P[17][12]*q0)/2;
-    nextP[17][4] = P[17][4] + P[17][1]*SF[0] + P[17][0]*SF[2] + P[17][2]*SPP[0] - P[17][3]*SPP[2];
-    nextP[17][5] = P[17][5] + P[17][0]*SF[1] + P[17][2]*SF[0] + P[17][3]*SF[2] - P[17][1]*SPP[0];
-    nextP[17][6] = P[17][6] + P[17][1]*SF[1] + P[17][3]*SF[0] + P[17][0]*SPP[0] - P[17][2]*SPP[1];
-    nextP[17][7] = P[17][7] + P[17][4]*dt;
-    nextP[17][8] = P[17][8] + P[17][5]*dt;
-    nextP[17][9] = P[17][9] + P[17][6]*dt;
-    nextP[17][10] = P[17][10];
-    nextP[17][11] = P[17][11];
-    nextP[17][12] = P[17][12];
-    nextP[17][13] = P[17][13];
-    nextP[17][14] = P[17][14];
-    nextP[17][15] = P[17][15];
-    nextP[17][16] = P[17][16];
-    nextP[17][17] = P[17][17];
-    nextP[17][18] = P[17][18];
-    nextP[17][19] = P[17][19];
-    nextP[17][20] = P[17][20];
-    nextP[18][0] = P[18][0] + P[18][1]*SF[6] + P[18][2]*SPP[7] + P[18][3]*SPP[6] + P[18][10]*SPP[5] + P[18][11]*SPP[4] + P[18][12]*SPP[3];
-    nextP[18][1] = P[18][1] + P[18][0]*SF[5] + P[18][2]*SF[4] + P[18][3]*SPP[7] + P[18][11]*SPP[3] - P[18][12]*SPP[4] - (P[18][10]*q0)/2;
-    nextP[18][2] = P[18][2] + P[18][0]*SF[3] + P[18][3]*SF[5] + P[18][1]*SPP[6] - P[18][10]*SPP[3] + P[18][12]*SPP[5] - (P[18][11]*q0)/2;
-    nextP[18][3] = P[18][3] + P[18][0]*SF[4] + P[18][1]*SF[3] + P[18][2]*SF[6] + P[18][10]*SPP[4] - P[18][11]*SPP[5] - (P[18][12]*q0)/2;
-    nextP[18][4] = P[18][4] + P[18][1]*SF[0] + P[18][0]*SF[2] + P[18][2]*SPP[0] - P[18][3]*SPP[2];
-    nextP[18][5] = P[18][5] + P[18][0]*SF[1] + P[18][2]*SF[0] + P[18][3]*SF[2] - P[18][1]*SPP[0];
-    nextP[18][6] = P[18][6] + P[18][1]*SF[1] + P[18][3]*SF[0] + P[18][0]*SPP[0] - P[18][2]*SPP[1];
-    nextP[18][7] = P[18][7] + P[18][4]*dt;
-    nextP[18][8] = P[18][8] + P[18][5]*dt;
-    nextP[18][9] = P[18][9] + P[18][6]*dt;
-    nextP[18][10] = P[18][10];
-    nextP[18][11] = P[18][11];
-    nextP[18][12] = P[18][12];
-    nextP[18][13] = P[18][13];
-    nextP[18][14] = P[18][14];
-    nextP[18][15] = P[18][15];
-    nextP[18][16] = P[18][16];
-    nextP[18][17] = P[18][17];
-    nextP[18][18] = P[18][18];
-    nextP[18][19] = P[18][19];
-    nextP[18][20] = P[18][20];
-    nextP[19][0] = P[19][0] + P[19][1]*SF[6] + P[19][2]*SPP[7] + P[19][3]*SPP[6] + P[19][10]*SPP[5] + P[19][11]*SPP[4] + P[19][12]*SPP[3];
-    nextP[19][1] = P[19][1] + P[19][0]*SF[5] + P[19][2]*SF[4] + P[19][3]*SPP[7] + P[19][11]*SPP[3] - P[19][12]*SPP[4] - (P[19][10]*q0)/2;
-    nextP[19][2] = P[19][2] + P[19][0]*SF[3] + P[19][3]*SF[5] + P[19][1]*SPP[6] - P[19][10]*SPP[3] + P[19][12]*SPP[5] - (P[19][11]*q0)/2;
-    nextP[19][3] = P[19][3] + P[19][0]*SF[4] + P[19][1]*SF[3] + P[19][2]*SF[6] + P[19][10]*SPP[4] - P[19][11]*SPP[5] - (P[19][12]*q0)/2;
-    nextP[19][4] = P[19][4] + P[19][1]*SF[0] + P[19][0]*SF[2] + P[19][2]*SPP[0] - P[19][3]*SPP[2];
-    nextP[19][5] = P[19][5] + P[19][0]*SF[1] + P[19][2]*SF[0] + P[19][3]*SF[2] - P[19][1]*SPP[0];
-    nextP[19][6] = P[19][6] + P[19][1]*SF[1] + P[19][3]*SF[0] + P[19][0]*SPP[0] - P[19][2]*SPP[1];
-    nextP[19][7] = P[19][7] + P[19][4]*dt;
-    nextP[19][8] = P[19][8] + P[19][5]*dt;
-    nextP[19][9] = P[19][9] + P[19][6]*dt;
-    nextP[19][10] = P[19][10];
-    nextP[19][11] = P[19][11];
-    nextP[19][12] = P[19][12];
-    nextP[19][13] = P[19][13];
-    nextP[19][14] = P[19][14];
-    nextP[19][15] = P[19][15];
-    nextP[19][16] = P[19][16];
-    nextP[19][17] = P[19][17];
-    nextP[19][18] = P[19][18];
-    nextP[19][19] = P[19][19];
-    nextP[19][20] = P[19][20];
-    nextP[20][0] = P[20][0] + P[20][1]*SF[6] + P[20][2]*SPP[7] + P[20][3]*SPP[6] + P[20][10]*SPP[5] + P[20][11]*SPP[4] + P[20][12]*SPP[3];
-    nextP[20][1] = P[20][1] + P[20][0]*SF[5] + P[20][2]*SF[4] + P[20][3]*SPP[7] + P[20][11]*SPP[3] - P[20][12]*SPP[4] - (P[20][10]*q0)/2;
-    nextP[20][2] = P[20][2] + P[20][0]*SF[3] + P[20][3]*SF[5] + P[20][1]*SPP[6] - P[20][10]*SPP[3] + P[20][12]*SPP[5] - (P[20][11]*q0)/2;
-    nextP[20][3] = P[20][3] + P[20][0]*SF[4] + P[20][1]*SF[3] + P[20][2]*SF[6] + P[20][10]*SPP[4] - P[20][11]*SPP[5] - (P[20][12]*q0)/2;
-    nextP[20][4] = P[20][4] + P[20][1]*SF[0] + P[20][0]*SF[2] + P[20][2]*SPP[0] - P[20][3]*SPP[2];
-    nextP[20][5] = P[20][5] + P[20][0]*SF[1] + P[20][2]*SF[0] + P[20][3]*SF[2] - P[20][1]*SPP[0];
-    nextP[20][6] = P[20][6] + P[20][1]*SF[1] + P[20][3]*SF[0] + P[20][0]*SPP[0] - P[20][2]*SPP[1];
-    nextP[20][7] = P[20][7] + P[20][4]*dt;
-    nextP[20][8] = P[20][8] + P[20][5]*dt;
-    nextP[20][9] = P[20][9] + P[20][6]*dt;
-    nextP[20][10] = P[20][10];
-    nextP[20][11] = P[20][11];
-    nextP[20][12] = P[20][12];
-    nextP[20][13] = P[20][13];
-    nextP[20][14] = P[20][14];
-    nextP[20][15] = P[20][15];
-    nextP[20][16] = P[20][16];
-    nextP[20][17] = P[20][17];
-    nextP[20][18] = P[20][18];
-    nextP[20][19] = P[20][19];
-    nextP[20][20] = P[20][20];
-
-    for (unsigned i = 0; i < n_states; i++)
-    {
-        nextP[i][i] = nextP[i][i] + processNoise[i];
-    }
-
-    // If on ground or no magnetometer fitted, inhibit magnetometer bias updates by
-    // setting the coresponding covariance terms to zero.
-    if (onGround || !useCompass)
-    {
-        zeroRows(nextP,15,20);
-        zeroCols(nextP,15,20);
-    }
-
-    // If on ground or not using airspeed sensing, inhibit wind velocity
-    // covariance growth.
-    if (onGround || !useAirspeed)
-    {
-        zeroRows(nextP,13,14);
-        zeroCols(nextP,13,14);
-    }
-
-    // If the total position variance exceds 1E6 (1000m), then stop covariance
-    // growth by setting the predicted to the previous values
-    // This prevent an ill conditioned matrix from occurring for long periods
-    // without GPS
-    if ((P[7][7] + P[8][8]) > 1E6f)
-    {
-        for (uint8_t i=7; i<=8; i++)
-        {
-            for (unsigned j = 0; j < n_states; j++)
-            {
-                nextP[i][j] = P[i][j];
-                nextP[j][i] = P[j][i];
-            }
-        }
-    }
-
-    if (onGround || staticMode) {
-        // copy the portion of the variances we want to
-        // propagate
-        for (unsigned i = 0; i < 14; i++) {
-            P[i][i] = nextP[i][i];
-
-            // force symmetry for observable states
-            // force zero for non-observable states
-            for (unsigned i = 1; i < n_states; i++)
-            {
-                for (uint8_t j = 0; j < i; j++)
-                {
-                    if ((i > 12) || (j > 12)) {
-                        P[i][j] = 0.0f;
-                    } else {
-                        P[i][j] = 0.5f * (nextP[i][j] + nextP[j][i]);
-                    }
-                    P[j][i] = P[i][j];
-                }
-            }
-        }
-
-    } else {
-
-        // Copy covariance
-        for (unsigned i = 0; i < n_states; i++) {
-            P[i][i] = nextP[i][i];
-        }
-
-        // force symmetry for observable states
-        for (unsigned i = 1; i < n_states; i++)
-        {
-            for (uint8_t j = 0; j < i; j++)
-            {
-                P[i][j] = 0.5f * (nextP[i][j] + nextP[j][i]);
-                P[j][i] = P[i][j];
-            }
-        }
-
-    }
-
-    ConstrainVariances();
-}
-
-void AttPosEKF::FuseVelposNED()
-{
-
-// declare variables used by fault isolation logic
-    uint32_t gpsRetryTime = 30000; // time in msec before GPS fusion will be retried following innovation consistency failure
-    uint32_t gpsRetryTimeNoTAS = 5000; // retry time if no TAS measurement available
-    uint32_t hgtRetryTime = 5000; // height measurement retry time
-    uint32_t horizRetryTime;
-
-// declare variables used to check measurement errors
-    float velInnov[3] = {0.0f,0.0f,0.0f};
-    float posInnov[2] = {0.0f,0.0f};
-    float hgtInnov = 0.0f;
-
-// declare variables used to control access to arrays
-    bool fuseData[6] = {false,false,false,false,false,false};
-    uint8_t stateIndex;
-    uint8_t obsIndex;
-    uint8_t indexLimit;
-
-// declare variables used by state and covariance update calculations
-    float velErr;
-    float posErr;
-    float R_OBS[6];
-    float observation[6];
-    float SK;
-    float quatMag;
-
-// Perform sequential fusion of GPS measurements. This assumes that the
-// errors in the different velocity and position components are
-// uncorrelated which is not true, however in the absence of covariance
-// data from the GPS receiver it is the only assumption we can make
-// so we might as well take advantage of the computational efficiencies
-// associated with sequential fusion
-    if (fuseVelData || fusePosData || fuseHgtData)
-    {
-        // set the GPS data timeout depending on whether airspeed data is present
-        if (useAirspeed) horizRetryTime = gpsRetryTime;
-        else horizRetryTime = gpsRetryTimeNoTAS;
-
-        // Form the observation vector
-        for (uint8_t i=0; i<=2; i++) observation[i] = velNED[i];
-        for (uint8_t i=3; i<=4; i++) observation[i] = posNE[i-3];
-        observation[5] = -(hgtMea);
-
-        // Estimate the GPS Velocity, GPS horiz position and height measurement variances.
-        velErr = 0.2f*accNavMag; // additional error in GPS velocities caused by manoeuvring
-        posErr = 0.2f*accNavMag; // additional error in GPS position caused by manoeuvring
-        R_OBS[0] = 0.04f + sq(velErr);
-        R_OBS[1] = R_OBS[0];
-        R_OBS[2] = 0.08f + sq(velErr);
-        R_OBS[3] = R_OBS[2];
-        R_OBS[4] = 4.0f  + sq(posErr);
-        R_OBS[5] = 4.0f;
-
-        // Set innovation variances to zero default
-        for (uint8_t i = 0; i<=5; i++)
-        {
-            varInnovVelPos[i] = 0.0f;
-        }
-        // calculate innovations and check GPS data validity using an innovation consistency check
-        if (fuseVelData)
-        {
-            // test velocity measurements
-            uint8_t imax = 2;
-            if (fusionModeGPS == 1) imax = 1;
-            for (uint8_t i = 0; i<=imax; i++)
-            {
-                velInnov[i] = statesAtVelTime[i+4] - velNED[i];
-                stateIndex = 4 + i;
-                varInnovVelPos[i] = P[stateIndex][stateIndex] + R_OBS[i];
-            }
-            // apply a 5-sigma threshold
-            current_ekf_state.velHealth = (sq(velInnov[0]) + sq(velInnov[1]) + sq(velInnov[2])) < 25.0f * (varInnovVelPos[0] + varInnovVelPos[1] + varInnovVelPos[2]);
-            current_ekf_state.velTimeout = (millis() - current_ekf_state.velFailTime) > horizRetryTime;
-            if (current_ekf_state.velHealth || current_ekf_state.velTimeout)
-            {
-                current_ekf_state.velHealth = true;
-                current_ekf_state.velFailTime = millis();
-            }
-            else
-            {
-                current_ekf_state.velHealth = false;
-            }
-        }
-        if (fusePosData)
-        {
-            // test horizontal position measurements
-            posInnov[0] = statesAtPosTime[7] - posNE[0];
-            posInnov[1] = statesAtPosTime[8] - posNE[1];
-            varInnovVelPos[3] = P[7][7] + R_OBS[3];
-            varInnovVelPos[4] = P[8][8] + R_OBS[4];
-            // apply a 10-sigma threshold
-            current_ekf_state.posHealth = (sq(posInnov[0]) + sq(posInnov[1])) < 100.0f*(varInnovVelPos[3] + varInnovVelPos[4]);
-            current_ekf_state.posTimeout = (millis() - current_ekf_state.posFailTime) > horizRetryTime;
-            if (current_ekf_state.posHealth || current_ekf_state.posTimeout)
-            {
-                current_ekf_state.posHealth = true;
-                current_ekf_state.posFailTime = millis();
-            }
-            else
-            {
-                current_ekf_state.posHealth = false;
-            }
-        }
-        // test height measurements
-        if (fuseHgtData)
-        {
-            hgtInnov = statesAtHgtTime[9] + hgtMea;
-            varInnovVelPos[5] = P[9][9] + R_OBS[5];
-            // apply a 10-sigma threshold
-            current_ekf_state.hgtHealth = sq(hgtInnov) < 100.0f*varInnovVelPos[5];
-            current_ekf_state.hgtTimeout = (millis() - current_ekf_state.hgtFailTime) > hgtRetryTime;
-            if (current_ekf_state.hgtHealth || current_ekf_state.hgtTimeout)
-            {
-                current_ekf_state.hgtHealth = true;
-                current_ekf_state.hgtFailTime = millis();
-            }
-            else
-            {
-                current_ekf_state.hgtHealth = false;
-            }
-        }
-        // Set range for sequential fusion of velocity and position measurements depending
-        // on which data is available and its health
-        if (fuseVelData && fusionModeGPS == 0 && current_ekf_state.velHealth)
-        {
-            fuseData[0] = true;
-            fuseData[1] = true;
-            fuseData[2] = true;
-        }
-        if (fuseVelData && fusionModeGPS == 1 && current_ekf_state.velHealth)
-        {
-            fuseData[0] = true;
-            fuseData[1] = true;
-        }
-        if (fusePosData && fusionModeGPS <= 2 && current_ekf_state.posHealth)
-        {
-            fuseData[3] = true;
-            fuseData[4] = true;
-        }
-        if (fuseHgtData && current_ekf_state.hgtHealth)
-        {
-            fuseData[5] = true;
-        }
-        // Limit range of states modified when on ground
-        if(!onGround)
-        {
-            indexLimit = 20;
-        }
-        else
-        {
-            indexLimit = 12;
-        }
-        // Fuse measurements sequentially
-        for (obsIndex=0; obsIndex<=5; obsIndex++)
-        {
-            if (fuseData[obsIndex])
-            {
-                stateIndex = 4 + obsIndex;
-                // Calculate the measurement innovation, using states from a
-                // different time coordinate if fusing height data
-                if (obsIndex >= 0 && obsIndex <= 2)
-                {
-                    innovVelPos[obsIndex] = statesAtVelTime[stateIndex] - observation[obsIndex];
-                }
-                else if (obsIndex == 3 || obsIndex == 4)
-                {
-                    innovVelPos[obsIndex] = statesAtPosTime[stateIndex] - observation[obsIndex];
-                }
-                else if (obsIndex == 5)
-                {
-                    innovVelPos[obsIndex] = statesAtHgtTime[stateIndex] - observation[obsIndex];
-                }
-                // Calculate the Kalman Gain
-                // Calculate innovation variances - also used for data logging
-                varInnovVelPos[obsIndex] = P[stateIndex][stateIndex] + R_OBS[obsIndex];
-                SK = 1.0/varInnovVelPos[obsIndex];
-                for (uint8_t i= 0; i<=indexLimit; i++)
-                {
-                    Kfusion[i] = P[i][stateIndex]*SK;
-                }
-                // Calculate state corrections and re-normalise the quaternions
-                for (uint8_t i = 0; i<=indexLimit; i++)
-                {
-                    states[i] = states[i] - Kfusion[i] * innovVelPos[obsIndex];
-                }
-                quatMag = sqrt(states[0]*states[0] + states[1]*states[1] + states[2]*states[2] + states[3]*states[3]);
-                if (quatMag > 1e-12f) // divide by  0 protection
-                {
-                    for (uint8_t i = 0; i<=3; i++)
-                    {
-                        states[i] = states[i] / quatMag;
-                    }
-                }
-                // Update the covariance - take advantage of direct observation of a
-                // single state at index = stateIndex to reduce computations
-                // Optimised implementation of standard equation P = (I - K*H)*P;
-                for (uint8_t i= 0; i<=indexLimit; i++)
-                {
-                    for (uint8_t j= 0; j<=indexLimit; j++)
-                    {
-                        KHP[i][j] = Kfusion[i] * P[stateIndex][j];
-                    }
-                }
-                for (uint8_t i= 0; i<=indexLimit; i++)
-                {
-                    for (uint8_t j= 0; j<=indexLimit; j++)
-                    {
-                        P[i][j] = P[i][j] - KHP[i][j];
-                    }
-                }
-            }
-        }
-    }
-
-    ForceSymmetry();
-    ConstrainVariances();
-
-    //printf("velh: %s, posh: %s, hgth: %s\n", ((velHealth) ? "OK" : "FAIL"), ((posHealth) ? "OK" : "FAIL"), ((hgtHealth) ? "OK" : "FAIL"));
-}
-
-void AttPosEKF::FuseMagnetometer()
-{
-    uint8_t obsIndex;
-    uint8_t indexLimit;
-    float DCM[3][3] =
-    {
-        {1.0f,0.0f,0.0f} ,
-        {0.0f,1.0f,0.0f} ,
-        {0.0f,0.0f,1.0f}
-    };
-    float MagPred[3] = {0.0f,0.0f,0.0f};
-    float SK_MX[6];
-    float SK_MY[5];
-    float SK_MZ[6];
-    float SH_MAG[9] = {0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f};
-
-// Perform sequential fusion of Magnetometer measurements.
-// This assumes that the errors in the different components are
-// uncorrelated which is not true, however in the absence of covariance
-// data fit is the only assumption we can make
-// so we might as well take advantage of the computational efficiencies
-// associated with sequential fusion
-    if (useCompass && (fuseMagData || obsIndex == 1 || obsIndex == 2))
-    {
-        // Limit range of states modified when on ground
-        if(!onGround)
-        {
-            indexLimit = 20;
-        }
-        else
-        {
-            indexLimit = 12;
-        }
-
-        static float q0 = 0.0f;
-        static float q1 = 0.0f;
-        static float q2 = 0.0f;
-        static float q3 = 1.0f;
-        static float magN = 0.4f;
-        static float magE = 0.0f;
-        static float magD = 0.3f;
-
-        static float R_MAG = 0.0025f;
-
-        float H_MAG[21] = {0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f};
-
-        // Sequential fusion of XYZ components to spread processing load across
-        // three prediction time steps.
-
-        // Calculate observation jacobians and Kalman gains
-        if (fuseMagData)
-        {
-            static float magXbias = 0.0f;
-            static float magYbias = 0.0f;
-            static float magZbias = 0.0f;
-
-            // Copy required states to local variable names
-            q0       = statesAtMagMeasTime[0];
-            q1       = statesAtMagMeasTime[1];
-            q2       = statesAtMagMeasTime[2];
-            q3       = statesAtMagMeasTime[3];
-            magN     = statesAtMagMeasTime[15];
-            magE     = statesAtMagMeasTime[16];
-            magD     = statesAtMagMeasTime[17];
-            magXbias = statesAtMagMeasTime[18];
-            magYbias = statesAtMagMeasTime[19];
-            magZbias = statesAtMagMeasTime[20];
-
-            // rotate predicted earth components into body axes and calculate
-            // predicted measurments
-            DCM[0][0] = q0*q0 + q1*q1 - q2*q2 - q3*q3;
-            DCM[0][1] = 2*(q1*q2 + q0*q3);
-            DCM[0][2] = 2*(q1*q3-q0*q2);
-            DCM[1][0] = 2*(q1*q2 - q0*q3);
-            DCM[1][1] = q0*q0 - q1*q1 + q2*q2 - q3*q3;
-            DCM[1][2] = 2*(q2*q3 + q0*q1);
-            DCM[2][0] = 2*(q1*q3 + q0*q2);
-            DCM[2][1] = 2*(q2*q3 - q0*q1);
-            DCM[2][2] = q0*q0 - q1*q1 - q2*q2 + q3*q3;
-            MagPred[0] = DCM[0][0]*magN + DCM[0][1]*magE  + DCM[0][2]*magD + magXbias;
-            MagPred[1] = DCM[1][0]*magN + DCM[1][1]*magE  + DCM[1][2]*magD + magYbias;
-            MagPred[2] = DCM[2][0]*magN + DCM[2][1]*magE  + DCM[2][2]*magD + magZbias;
-
-            // scale magnetometer observation error with total angular rate
-            R_MAG = 0.0025f + sq(0.05f*dAngIMU.length()/dtIMU);
-
-            // Calculate observation jacobians
-            SH_MAG[0] = 2*magD*q3 + 2*magE*q2 + 2*magN*q1;
-            SH_MAG[1] = 2*magD*q0 - 2*magE*q1 + 2*magN*q2;
-            SH_MAG[2] = 2*magD*q1 + 2*magE*q0 - 2*magN*q3;
-            SH_MAG[3] = sq(q3);
-            SH_MAG[4] = sq(q2);
-            SH_MAG[5] = sq(q1);
-            SH_MAG[6] = sq(q0);
-            SH_MAG[7] = 2*magN*q0;
-            SH_MAG[8] = 2*magE*q3;
-
-            for (uint8_t i=0; i<=20; i++) H_MAG[i] = 0;
-            H_MAG[0] = SH_MAG[7] + SH_MAG[8] - 2*magD*q2;
-            H_MAG[1] = SH_MAG[0];
-            H_MAG[2] = 2*magE*q1 - 2*magD*q0 - 2*magN*q2;
-            H_MAG[3] = SH_MAG[2];
-            H_MAG[15] = SH_MAG[5] - SH_MAG[4] - SH_MAG[3] + SH_MAG[6];
-            H_MAG[16] = 2*q0*q3 + 2*q1*q2;
-            H_MAG[17] = 2*q1*q3 - 2*q0*q2;
-            H_MAG[18] = 1.0f;
-
-            // Calculate Kalman gain
-            SK_MX[0] = 1/(P[18][18] + R_MAG + P[1][18]*SH_MAG[0] + P[3][18]*SH_MAG[2] - P[15][18]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) - (2*magD*q0 - 2*magE*q1 + 2*magN*q2)*(P[18][2] + P[1][2]*SH_MAG[0] + P[3][2]*SH_MAG[2] - P[15][2]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[16][2]*(2*q0*q3 + 2*q1*q2) - P[17][2]*(2*q0*q2 - 2*q1*q3) - P[2][2]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][2]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + (SH_MAG[7] + SH_MAG[8] - 2*magD*q2)*(P[18][0] + P[1][0]*SH_MAG[0] + P[3][0]*SH_MAG[2] - P[15][0]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[16][0]*(2*q0*q3 + 2*q1*q2) - P[17][0]*(2*q0*q2 - 2*q1*q3) - P[2][0]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][0]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + SH_MAG[0]*(P[18][1] + P[1][1]*SH_MAG[0] + P[3][1]*SH_MAG[2] - P[15][1]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[16][1]*(2*q0*q3 + 2*q1*q2) - P[17][1]*(2*q0*q2 - 2*q1*q3) - P[2][1]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][1]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + SH_MAG[2]*(P[18][3] + P[1][3]*SH_MAG[0] + P[3][3]*SH_MAG[2] - P[15][3]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[16][3]*(2*q0*q3 + 2*q1*q2) - P[17][3]*(2*q0*q2 - 2*q1*q3) - P[2][3]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][3]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - (SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6])*(P[18][15] + P[1][15]*SH_MAG[0] + P[3][15]*SH_MAG[2] - P[15][15]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[16][15]*(2*q0*q3 + 2*q1*q2) - P[17][15]*(2*q0*q2 - 2*q1*q3) - P[2][15]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][15]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + P[16][18]*(2*q0*q3 + 2*q1*q2) - P[17][18]*(2*q0*q2 - 2*q1*q3) - P[2][18]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + (2*q0*q3 + 2*q1*q2)*(P[18][16] + P[1][16]*SH_MAG[0] + P[3][16]*SH_MAG[2] - P[15][16]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[16][16]*(2*q0*q3 + 2*q1*q2) - P[17][16]*(2*q0*q2 - 2*q1*q3) - P[2][16]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][16]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - (2*q0*q2 - 2*q1*q3)*(P[18][17] + P[1][17]*SH_MAG[0] + P[3][17]*SH_MAG[2] - P[15][17]*(SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6]) + P[16][17]*(2*q0*q3 + 2*q1*q2) - P[17][17]*(2*q0*q2 - 2*q1*q3) - P[2][17]*(2*magD*q0 - 2*magE*q1 + 2*magN*q2) + P[0][17]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + P[0][18]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2));
-            SK_MX[1] = SH_MAG[3] + SH_MAG[4] - SH_MAG[5] - SH_MAG[6];
-            SK_MX[2] = 2*magD*q0 - 2*magE*q1 + 2*magN*q2;
-            SK_MX[3] = SH_MAG[7] + SH_MAG[8] - 2*magD*q2;
-            SK_MX[4] = 2*q0*q2 - 2*q1*q3;
-            SK_MX[5] = 2*q0*q3 + 2*q1*q2;
-            Kfusion[0] = SK_MX[0]*(P[0][18] + P[0][1]*SH_MAG[0] + P[0][3]*SH_MAG[2] + P[0][0]*SK_MX[3] - P[0][2]*SK_MX[2] - P[0][15]*SK_MX[1] + P[0][16]*SK_MX[5] - P[0][17]*SK_MX[4]);
-            Kfusion[1] = SK_MX[0]*(P[1][18] + P[1][1]*SH_MAG[0] + P[1][3]*SH_MAG[2] + P[1][0]*SK_MX[3] - P[1][2]*SK_MX[2] - P[1][15]*SK_MX[1] + P[1][16]*SK_MX[5] - P[1][17]*SK_MX[4]);
-            Kfusion[2] = SK_MX[0]*(P[2][18] + P[2][1]*SH_MAG[0] + P[2][3]*SH_MAG[2] + P[2][0]*SK_MX[3] - P[2][2]*SK_MX[2] - P[2][15]*SK_MX[1] + P[2][16]*SK_MX[5] - P[2][17]*SK_MX[4]);
-            Kfusion[3] = SK_MX[0]*(P[3][18] + P[3][1]*SH_MAG[0] + P[3][3]*SH_MAG[2] + P[3][0]*SK_MX[3] - P[3][2]*SK_MX[2] - P[3][15]*SK_MX[1] + P[3][16]*SK_MX[5] - P[3][17]*SK_MX[4]);
-            Kfusion[4] = SK_MX[0]*(P[4][18] + P[4][1]*SH_MAG[0] + P[4][3]*SH_MAG[2] + P[4][0]*SK_MX[3] - P[4][2]*SK_MX[2] - P[4][15]*SK_MX[1] + P[4][16]*SK_MX[5] - P[4][17]*SK_MX[4]);
-            Kfusion[5] = SK_MX[0]*(P[5][18] + P[5][1]*SH_MAG[0] + P[5][3]*SH_MAG[2] + P[5][0]*SK_MX[3] - P[5][2]*SK_MX[2] - P[5][15]*SK_MX[1] + P[5][16]*SK_MX[5] - P[5][17]*SK_MX[4]);
-            Kfusion[6] = SK_MX[0]*(P[6][18] + P[6][1]*SH_MAG[0] + P[6][3]*SH_MAG[2] + P[6][0]*SK_MX[3] - P[6][2]*SK_MX[2] - P[6][15]*SK_MX[1] + P[6][16]*SK_MX[5] - P[6][17]*SK_MX[4]);
-            Kfusion[7] = SK_MX[0]*(P[7][18] + P[7][1]*SH_MAG[0] + P[7][3]*SH_MAG[2] + P[7][0]*SK_MX[3] - P[7][2]*SK_MX[2] - P[7][15]*SK_MX[1] + P[7][16]*SK_MX[5] - P[7][17]*SK_MX[4]);
-            Kfusion[8] = SK_MX[0]*(P[8][18] + P[8][1]*SH_MAG[0] + P[8][3]*SH_MAG[2] + P[8][0]*SK_MX[3] - P[8][2]*SK_MX[2] - P[8][15]*SK_MX[1] + P[8][16]*SK_MX[5] - P[8][17]*SK_MX[4]);
-            Kfusion[9] = SK_MX[0]*(P[9][18] + P[9][1]*SH_MAG[0] + P[9][3]*SH_MAG[2] + P[9][0]*SK_MX[3] - P[9][2]*SK_MX[2] - P[9][15]*SK_MX[1] + P[9][16]*SK_MX[5] - P[9][17]*SK_MX[4]);
-            Kfusion[10] = SK_MX[0]*(P[10][18] + P[10][1]*SH_MAG[0] + P[10][3]*SH_MAG[2] + P[10][0]*SK_MX[3] - P[10][2]*SK_MX[2] - P[10][15]*SK_MX[1] + P[10][16]*SK_MX[5] - P[10][17]*SK_MX[4]);
-            Kfusion[11] = SK_MX[0]*(P[11][18] + P[11][1]*SH_MAG[0] + P[11][3]*SH_MAG[2] + P[11][0]*SK_MX[3] - P[11][2]*SK_MX[2] - P[11][15]*SK_MX[1] + P[11][16]*SK_MX[5] - P[11][17]*SK_MX[4]);
-            Kfusion[12] = SK_MX[0]*(P[12][18] + P[12][1]*SH_MAG[0] + P[12][3]*SH_MAG[2] + P[12][0]*SK_MX[3] - P[12][2]*SK_MX[2] - P[12][15]*SK_MX[1] + P[12][16]*SK_MX[5] - P[12][17]*SK_MX[4]);
-            Kfusion[13] = SK_MX[0]*(P[13][18] + P[13][1]*SH_MAG[0] + P[13][3]*SH_MAG[2] + P[13][0]*SK_MX[3] - P[13][2]*SK_MX[2] - P[13][15]*SK_MX[1] + P[13][16]*SK_MX[5] - P[13][17]*SK_MX[4]);
-            Kfusion[14] = SK_MX[0]*(P[14][18] + P[14][1]*SH_MAG[0] + P[14][3]*SH_MAG[2] + P[14][0]*SK_MX[3] - P[14][2]*SK_MX[2] - P[14][15]*SK_MX[1] + P[14][16]*SK_MX[5] - P[14][17]*SK_MX[4]);
-            Kfusion[15] = SK_MX[0]*(P[15][18] + P[15][1]*SH_MAG[0] + P[15][3]*SH_MAG[2] + P[15][0]*SK_MX[3] - P[15][2]*SK_MX[2] - P[15][15]*SK_MX[1] + P[15][16]*SK_MX[5] - P[15][17]*SK_MX[4]);
-            Kfusion[16] = SK_MX[0]*(P[16][18] + P[16][1]*SH_MAG[0] + P[16][3]*SH_MAG[2] + P[16][0]*SK_MX[3] - P[16][2]*SK_MX[2] - P[16][15]*SK_MX[1] + P[16][16]*SK_MX[5] - P[16][17]*SK_MX[4]);
-            Kfusion[17] = SK_MX[0]*(P[17][18] + P[17][1]*SH_MAG[0] + P[17][3]*SH_MAG[2] + P[17][0]*SK_MX[3] - P[17][2]*SK_MX[2] - P[17][15]*SK_MX[1] + P[17][16]*SK_MX[5] - P[17][17]*SK_MX[4]);
-            Kfusion[18] = SK_MX[0]*(P[18][18] + P[18][1]*SH_MAG[0] + P[18][3]*SH_MAG[2] + P[18][0]*SK_MX[3] - P[18][2]*SK_MX[2] - P[18][15]*SK_MX[1] + P[18][16]*SK_MX[5] - P[18][17]*SK_MX[4]);
-            Kfusion[19] = SK_MX[0]*(P[19][18] + P[19][1]*SH_MAG[0] + P[19][3]*SH_MAG[2] + P[19][0]*SK_MX[3] - P[19][2]*SK_MX[2] - P[19][15]*SK_MX[1] + P[19][16]*SK_MX[5] - P[19][17]*SK_MX[4]);
-            Kfusion[20] = SK_MX[0]*(P[20][18] + P[20][1]*SH_MAG[0] + P[20][3]*SH_MAG[2] + P[20][0]*SK_MX[3] - P[20][2]*SK_MX[2] - P[20][15]*SK_MX[1] + P[20][16]*SK_MX[5] - P[20][17]*SK_MX[4]);
-            varInnovMag[0] = 1.0f/SK_MX[0];
-            innovMag[0] = MagPred[0] - magData.x;
-
-            // reset the observation index to 0 (we start by fusing the X
-            // measurement)
-            obsIndex = 0;
-        }
-        else if (obsIndex == 1) // we are now fusing the Y measurement
-        {
-            // Calculate observation jacobians
-            for (unsigned int i=0; i<n_states; i++) H_MAG[i] = 0;
-            H_MAG[0] = SH_MAG[2];
-            H_MAG[1] = SH_MAG[1];
-            H_MAG[2] = SH_MAG[0];
-            H_MAG[3] = 2*magD*q2 - SH_MAG[8] - SH_MAG[7];
-            H_MAG[15] = 2*q1*q2 - 2*q0*q3;
-            H_MAG[16] = SH_MAG[4] - SH_MAG[3] - SH_MAG[5] + SH_MAG[6];
-            H_MAG[17] = 2*q0*q1 + 2*q2*q3;
-            H_MAG[19] = 1;
-
-            // Calculate Kalman gain
-            SK_MY[0] = 1/(P[19][19] + R_MAG + P[0][19]*SH_MAG[2] + P[1][19]*SH_MAG[1] + P[2][19]*SH_MAG[0] - P[16][19]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - (2*q0*q3 - 2*q1*q2)*(P[19][15] + P[0][15]*SH_MAG[2] + P[1][15]*SH_MAG[1] + P[2][15]*SH_MAG[0] - P[16][15]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[15][15]*(2*q0*q3 - 2*q1*q2) + P[17][15]*(2*q0*q1 + 2*q2*q3) - P[3][15]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + (2*q0*q1 + 2*q2*q3)*(P[19][17] + P[0][17]*SH_MAG[2] + P[1][17]*SH_MAG[1] + P[2][17]*SH_MAG[0] - P[16][17]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[15][17]*(2*q0*q3 - 2*q1*q2) + P[17][17]*(2*q0*q1 + 2*q2*q3) - P[3][17]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - (SH_MAG[7] + SH_MAG[8] - 2*magD*q2)*(P[19][3] + P[0][3]*SH_MAG[2] + P[1][3]*SH_MAG[1] + P[2][3]*SH_MAG[0] - P[16][3]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[15][3]*(2*q0*q3 - 2*q1*q2) + P[17][3]*(2*q0*q1 + 2*q2*q3) - P[3][3]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - P[15][19]*(2*q0*q3 - 2*q1*q2) + P[17][19]*(2*q0*q1 + 2*q2*q3) + SH_MAG[2]*(P[19][0] + P[0][0]*SH_MAG[2] + P[1][0]*SH_MAG[1] + P[2][0]*SH_MAG[0] - P[16][0]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[15][0]*(2*q0*q3 - 2*q1*q2) + P[17][0]*(2*q0*q1 + 2*q2*q3) - P[3][0]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + SH_MAG[1]*(P[19][1] + P[0][1]*SH_MAG[2] + P[1][1]*SH_MAG[1] + P[2][1]*SH_MAG[0] - P[16][1]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[15][1]*(2*q0*q3 - 2*q1*q2) + P[17][1]*(2*q0*q1 + 2*q2*q3) - P[3][1]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + SH_MAG[0]*(P[19][2] + P[0][2]*SH_MAG[2] + P[1][2]*SH_MAG[1] + P[2][2]*SH_MAG[0] - P[16][2]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[15][2]*(2*q0*q3 - 2*q1*q2) + P[17][2]*(2*q0*q1 + 2*q2*q3) - P[3][2]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - (SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6])*(P[19][16] + P[0][16]*SH_MAG[2] + P[1][16]*SH_MAG[1] + P[2][16]*SH_MAG[0] - P[16][16]*(SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6]) - P[15][16]*(2*q0*q3 - 2*q1*q2) + P[17][16]*(2*q0*q1 + 2*q2*q3) - P[3][16]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - P[3][19]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2));
-            SK_MY[1] = SH_MAG[3] - SH_MAG[4] + SH_MAG[5] - SH_MAG[6];
-            SK_MY[2] = SH_MAG[7] + SH_MAG[8] - 2*magD*q2;
-            SK_MY[3] = 2*q0*q3 - 2*q1*q2;
-            SK_MY[4] = 2*q0*q1 + 2*q2*q3;
-            Kfusion[0] = SK_MY[0]*(P[0][19] + P[0][0]*SH_MAG[2] + P[0][1]*SH_MAG[1] + P[0][2]*SH_MAG[0] - P[0][3]*SK_MY[2] - P[0][16]*SK_MY[1] - P[0][15]*SK_MY[3] + P[0][17]*SK_MY[4]);
-            Kfusion[1] = SK_MY[0]*(P[1][19] + P[1][0]*SH_MAG[2] + P[1][1]*SH_MAG[1] + P[1][2]*SH_MAG[0] - P[1][3]*SK_MY[2] - P[1][16]*SK_MY[1] - P[1][15]*SK_MY[3] + P[1][17]*SK_MY[4]);
-            Kfusion[2] = SK_MY[0]*(P[2][19] + P[2][0]*SH_MAG[2] + P[2][1]*SH_MAG[1] + P[2][2]*SH_MAG[0] - P[2][3]*SK_MY[2] - P[2][16]*SK_MY[1] - P[2][15]*SK_MY[3] + P[2][17]*SK_MY[4]);
-            Kfusion[3] = SK_MY[0]*(P[3][19] + P[3][0]*SH_MAG[2] + P[3][1]*SH_MAG[1] + P[3][2]*SH_MAG[0] - P[3][3]*SK_MY[2] - P[3][16]*SK_MY[1] - P[3][15]*SK_MY[3] + P[3][17]*SK_MY[4]);
-            Kfusion[4] = SK_MY[0]*(P[4][19] + P[4][0]*SH_MAG[2] + P[4][1]*SH_MAG[1] + P[4][2]*SH_MAG[0] - P[4][3]*SK_MY[2] - P[4][16]*SK_MY[1] - P[4][15]*SK_MY[3] + P[4][17]*SK_MY[4]);
-            Kfusion[5] = SK_MY[0]*(P[5][19] + P[5][0]*SH_MAG[2] + P[5][1]*SH_MAG[1] + P[5][2]*SH_MAG[0] - P[5][3]*SK_MY[2] - P[5][16]*SK_MY[1] - P[5][15]*SK_MY[3] + P[5][17]*SK_MY[4]);
-            Kfusion[6] = SK_MY[0]*(P[6][19] + P[6][0]*SH_MAG[2] + P[6][1]*SH_MAG[1] + P[6][2]*SH_MAG[0] - P[6][3]*SK_MY[2] - P[6][16]*SK_MY[1] - P[6][15]*SK_MY[3] + P[6][17]*SK_MY[4]);
-            Kfusion[7] = SK_MY[0]*(P[7][19] + P[7][0]*SH_MAG[2] + P[7][1]*SH_MAG[1] + P[7][2]*SH_MAG[0] - P[7][3]*SK_MY[2] - P[7][16]*SK_MY[1] - P[7][15]*SK_MY[3] + P[7][17]*SK_MY[4]);
-            Kfusion[8] = SK_MY[0]*(P[8][19] + P[8][0]*SH_MAG[2] + P[8][1]*SH_MAG[1] + P[8][2]*SH_MAG[0] - P[8][3]*SK_MY[2] - P[8][16]*SK_MY[1] - P[8][15]*SK_MY[3] + P[8][17]*SK_MY[4]);
-            Kfusion[9] = SK_MY[0]*(P[9][19] + P[9][0]*SH_MAG[2] + P[9][1]*SH_MAG[1] + P[9][2]*SH_MAG[0] - P[9][3]*SK_MY[2] - P[9][16]*SK_MY[1] - P[9][15]*SK_MY[3] + P[9][17]*SK_MY[4]);
-            Kfusion[10] = SK_MY[0]*(P[10][19] + P[10][0]*SH_MAG[2] + P[10][1]*SH_MAG[1] + P[10][2]*SH_MAG[0] - P[10][3]*SK_MY[2] - P[10][16]*SK_MY[1] - P[10][15]*SK_MY[3] + P[10][17]*SK_MY[4]);
-            Kfusion[11] = SK_MY[0]*(P[11][19] + P[11][0]*SH_MAG[2] + P[11][1]*SH_MAG[1] + P[11][2]*SH_MAG[0] - P[11][3]*SK_MY[2] - P[11][16]*SK_MY[1] - P[11][15]*SK_MY[3] + P[11][17]*SK_MY[4]);
-            Kfusion[12] = SK_MY[0]*(P[12][19] + P[12][0]*SH_MAG[2] + P[12][1]*SH_MAG[1] + P[12][2]*SH_MAG[0] - P[12][3]*SK_MY[2] - P[12][16]*SK_MY[1] - P[12][15]*SK_MY[3] + P[12][17]*SK_MY[4]);
-            Kfusion[13] = SK_MY[0]*(P[13][19] + P[13][0]*SH_MAG[2] + P[13][1]*SH_MAG[1] + P[13][2]*SH_MAG[0] - P[13][3]*SK_MY[2] - P[13][16]*SK_MY[1] - P[13][15]*SK_MY[3] + P[13][17]*SK_MY[4]);
-            Kfusion[14] = SK_MY[0]*(P[14][19] + P[14][0]*SH_MAG[2] + P[14][1]*SH_MAG[1] + P[14][2]*SH_MAG[0] - P[14][3]*SK_MY[2] - P[14][16]*SK_MY[1] - P[14][15]*SK_MY[3] + P[14][17]*SK_MY[4]);
-            Kfusion[15] = SK_MY[0]*(P[15][19] + P[15][0]*SH_MAG[2] + P[15][1]*SH_MAG[1] + P[15][2]*SH_MAG[0] - P[15][3]*SK_MY[2] - P[15][16]*SK_MY[1] - P[15][15]*SK_MY[3] + P[15][17]*SK_MY[4]);
-            Kfusion[16] = SK_MY[0]*(P[16][19] + P[16][0]*SH_MAG[2] + P[16][1]*SH_MAG[1] + P[16][2]*SH_MAG[0] - P[16][3]*SK_MY[2] - P[16][16]*SK_MY[1] - P[16][15]*SK_MY[3] + P[16][17]*SK_MY[4]);
-            Kfusion[17] = SK_MY[0]*(P[17][19] + P[17][0]*SH_MAG[2] + P[17][1]*SH_MAG[1] + P[17][2]*SH_MAG[0] - P[17][3]*SK_MY[2] - P[17][16]*SK_MY[1] - P[17][15]*SK_MY[3] + P[17][17]*SK_MY[4]);
-            Kfusion[18] = SK_MY[0]*(P[18][19] + P[18][0]*SH_MAG[2] + P[18][1]*SH_MAG[1] + P[18][2]*SH_MAG[0] - P[18][3]*SK_MY[2] - P[18][16]*SK_MY[1] - P[18][15]*SK_MY[3] + P[18][17]*SK_MY[4]);
-            Kfusion[19] = SK_MY[0]*(P[19][19] + P[19][0]*SH_MAG[2] + P[19][1]*SH_MAG[1] + P[19][2]*SH_MAG[0] - P[19][3]*SK_MY[2] - P[19][16]*SK_MY[1] - P[19][15]*SK_MY[3] + P[19][17]*SK_MY[4]);
-            Kfusion[20] = SK_MY[0]*(P[20][19] + P[20][0]*SH_MAG[2] + P[20][1]*SH_MAG[1] + P[20][2]*SH_MAG[0] - P[20][3]*SK_MY[2] - P[20][16]*SK_MY[1] - P[20][15]*SK_MY[3] + P[20][17]*SK_MY[4]);
-            varInnovMag[1] = 1.0f/SK_MY[0];
-            innovMag[1] = MagPred[1] - magData.y;
-        }
-        else if (obsIndex == 2) // we are now fusing the Z measurement
-        {
-            // Calculate observation jacobians
-            for (uint8_t i=0; i<=20; i++) H_MAG[i] = 0;
-            H_MAG[0] = SH_MAG[1];
-            H_MAG[1] = 2*magN*q3 - 2*magE*q0 - 2*magD*q1;
-            H_MAG[2] = SH_MAG[7] + SH_MAG[8] - 2*magD*q2;
-            H_MAG[3] = SH_MAG[0];
-            H_MAG[15] = 2*q0*q2 + 2*q1*q3;
-            H_MAG[16] = 2*q2*q3 - 2*q0*q1;
-            H_MAG[17] = SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6];
-            H_MAG[20] = 1;
-
-            // Calculate Kalman gain
-            SK_MZ[0] = 1/(P[20][20] + R_MAG + P[0][20]*SH_MAG[1] + P[3][20]*SH_MAG[0] + P[17][20]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) - (2*magD*q1 + 2*magE*q0 - 2*magN*q3)*(P[20][1] + P[0][1]*SH_MAG[1] + P[3][1]*SH_MAG[0] + P[17][1]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[15][1]*(2*q0*q2 + 2*q1*q3) - P[16][1]*(2*q0*q1 - 2*q2*q3) - P[1][1]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][1]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + (SH_MAG[7] + SH_MAG[8] - 2*magD*q2)*(P[20][2] + P[0][2]*SH_MAG[1] + P[3][2]*SH_MAG[0] + P[17][2]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[15][2]*(2*q0*q2 + 2*q1*q3) - P[16][2]*(2*q0*q1 - 2*q2*q3) - P[1][2]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][2]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + SH_MAG[1]*(P[20][0] + P[0][0]*SH_MAG[1] + P[3][0]*SH_MAG[0] + P[17][0]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[15][0]*(2*q0*q2 + 2*q1*q3) - P[16][0]*(2*q0*q1 - 2*q2*q3) - P[1][0]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][0]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + SH_MAG[0]*(P[20][3] + P[0][3]*SH_MAG[1] + P[3][3]*SH_MAG[0] + P[17][3]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[15][3]*(2*q0*q2 + 2*q1*q3) - P[16][3]*(2*q0*q1 - 2*q2*q3) - P[1][3]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][3]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + (SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6])*(P[20][17] + P[0][17]*SH_MAG[1] + P[3][17]*SH_MAG[0] + P[17][17]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[15][17]*(2*q0*q2 + 2*q1*q3) - P[16][17]*(2*q0*q1 - 2*q2*q3) - P[1][17]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][17]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + P[15][20]*(2*q0*q2 + 2*q1*q3) - P[16][20]*(2*q0*q1 - 2*q2*q3) - P[1][20]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + (2*q0*q2 + 2*q1*q3)*(P[20][15] + P[0][15]*SH_MAG[1] + P[3][15]*SH_MAG[0] + P[17][15]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[15][15]*(2*q0*q2 + 2*q1*q3) - P[16][15]*(2*q0*q1 - 2*q2*q3) - P[1][15]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][15]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) - (2*q0*q1 - 2*q2*q3)*(P[20][16] + P[0][16]*SH_MAG[1] + P[3][16]*SH_MAG[0] + P[17][16]*(SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6]) + P[15][16]*(2*q0*q2 + 2*q1*q3) - P[16][16]*(2*q0*q1 - 2*q2*q3) - P[1][16]*(2*magD*q1 + 2*magE*q0 - 2*magN*q3) + P[2][16]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2)) + P[2][20]*(SH_MAG[7] + SH_MAG[8] - 2*magD*q2));
-            SK_MZ[1] = SH_MAG[3] - SH_MAG[4] - SH_MAG[5] + SH_MAG[6];
-            SK_MZ[2] = 2*magD*q1 + 2*magE*q0 - 2*magN*q3;
-            SK_MZ[3] = SH_MAG[7] + SH_MAG[8] - 2*magD*q2;
-            SK_MZ[4] = 2*q0*q1 - 2*q2*q3;
-            SK_MZ[5] = 2*q0*q2 + 2*q1*q3;
-            Kfusion[0] = SK_MZ[0]*(P[0][20] + P[0][0]*SH_MAG[1] + P[0][3]*SH_MAG[0] - P[0][1]*SK_MZ[2] + P[0][2]*SK_MZ[3] + P[0][17]*SK_MZ[1] + P[0][15]*SK_MZ[5] - P[0][16]*SK_MZ[4]);
-            Kfusion[1] = SK_MZ[0]*(P[1][20] + P[1][0]*SH_MAG[1] + P[1][3]*SH_MAG[0] - P[1][1]*SK_MZ[2] + P[1][2]*SK_MZ[3] + P[1][17]*SK_MZ[1] + P[1][15]*SK_MZ[5] - P[1][16]*SK_MZ[4]);
-            Kfusion[2] = SK_MZ[0]*(P[2][20] + P[2][0]*SH_MAG[1] + P[2][3]*SH_MAG[0] - P[2][1]*SK_MZ[2] + P[2][2]*SK_MZ[3] + P[2][17]*SK_MZ[1] + P[2][15]*SK_MZ[5] - P[2][16]*SK_MZ[4]);
-            Kfusion[3] = SK_MZ[0]*(P[3][20] + P[3][0]*SH_MAG[1] + P[3][3]*SH_MAG[0] - P[3][1]*SK_MZ[2] + P[3][2]*SK_MZ[3] + P[3][17]*SK_MZ[1] + P[3][15]*SK_MZ[5] - P[3][16]*SK_MZ[4]);
-            Kfusion[4] = SK_MZ[0]*(P[4][20] + P[4][0]*SH_MAG[1] + P[4][3]*SH_MAG[0] - P[4][1]*SK_MZ[2] + P[4][2]*SK_MZ[3] + P[4][17]*SK_MZ[1] + P[4][15]*SK_MZ[5] - P[4][16]*SK_MZ[4]);
-            Kfusion[5] = SK_MZ[0]*(P[5][20] + P[5][0]*SH_MAG[1] + P[5][3]*SH_MAG[0] - P[5][1]*SK_MZ[2] + P[5][2]*SK_MZ[3] + P[5][17]*SK_MZ[1] + P[5][15]*SK_MZ[5] - P[5][16]*SK_MZ[4]);
-            Kfusion[6] = SK_MZ[0]*(P[6][20] + P[6][0]*SH_MAG[1] + P[6][3]*SH_MAG[0] - P[6][1]*SK_MZ[2] + P[6][2]*SK_MZ[3] + P[6][17]*SK_MZ[1] + P[6][15]*SK_MZ[5] - P[6][16]*SK_MZ[4]);
-            Kfusion[7] = SK_MZ[0]*(P[7][20] + P[7][0]*SH_MAG[1] + P[7][3]*SH_MAG[0] - P[7][1]*SK_MZ[2] + P[7][2]*SK_MZ[3] + P[7][17]*SK_MZ[1] + P[7][15]*SK_MZ[5] - P[7][16]*SK_MZ[4]);
-            Kfusion[8] = SK_MZ[0]*(P[8][20] + P[8][0]*SH_MAG[1] + P[8][3]*SH_MAG[0] - P[8][1]*SK_MZ[2] + P[8][2]*SK_MZ[3] + P[8][17]*SK_MZ[1] + P[8][15]*SK_MZ[5] - P[8][16]*SK_MZ[4]);
-            Kfusion[9] = SK_MZ[0]*(P[9][20] + P[9][0]*SH_MAG[1] + P[9][3]*SH_MAG[0] - P[9][1]*SK_MZ[2] + P[9][2]*SK_MZ[3] + P[9][17]*SK_MZ[1] + P[9][15]*SK_MZ[5] - P[9][16]*SK_MZ[4]);
-            Kfusion[10] = SK_MZ[0]*(P[10][20] + P[10][0]*SH_MAG[1] + P[10][3]*SH_MAG[0] - P[10][1]*SK_MZ[2] + P[10][2]*SK_MZ[3] + P[10][17]*SK_MZ[1] + P[10][15]*SK_MZ[5] - P[10][16]*SK_MZ[4]);
-            Kfusion[11] = SK_MZ[0]*(P[11][20] + P[11][0]*SH_MAG[1] + P[11][3]*SH_MAG[0] - P[11][1]*SK_MZ[2] + P[11][2]*SK_MZ[3] + P[11][17]*SK_MZ[1] + P[11][15]*SK_MZ[5] - P[11][16]*SK_MZ[4]);
-            Kfusion[12] = SK_MZ[0]*(P[12][20] + P[12][0]*SH_MAG[1] + P[12][3]*SH_MAG[0] - P[12][1]*SK_MZ[2] + P[12][2]*SK_MZ[3] + P[12][17]*SK_MZ[1] + P[12][15]*SK_MZ[5] - P[12][16]*SK_MZ[4]);
-            Kfusion[13] = SK_MZ[0]*(P[13][20] + P[13][0]*SH_MAG[1] + P[13][3]*SH_MAG[0] - P[13][1]*SK_MZ[2] + P[13][2]*SK_MZ[3] + P[13][17]*SK_MZ[1] + P[13][15]*SK_MZ[5] - P[13][16]*SK_MZ[4]);
-            Kfusion[14] = SK_MZ[0]*(P[14][20] + P[14][0]*SH_MAG[1] + P[14][3]*SH_MAG[0] - P[14][1]*SK_MZ[2] + P[14][2]*SK_MZ[3] + P[14][17]*SK_MZ[1] + P[14][15]*SK_MZ[5] - P[14][16]*SK_MZ[4]);
-            Kfusion[15] = SK_MZ[0]*(P[15][20] + P[15][0]*SH_MAG[1] + P[15][3]*SH_MAG[0] - P[15][1]*SK_MZ[2] + P[15][2]*SK_MZ[3] + P[15][17]*SK_MZ[1] + P[15][15]*SK_MZ[5] - P[15][16]*SK_MZ[4]);
-            Kfusion[16] = SK_MZ[0]*(P[16][20] + P[16][0]*SH_MAG[1] + P[16][3]*SH_MAG[0] - P[16][1]*SK_MZ[2] + P[16][2]*SK_MZ[3] + P[16][17]*SK_MZ[1] + P[16][15]*SK_MZ[5] - P[16][16]*SK_MZ[4]);
-            Kfusion[17] = SK_MZ[0]*(P[17][20] + P[17][0]*SH_MAG[1] + P[17][3]*SH_MAG[0] - P[17][1]*SK_MZ[2] + P[17][2]*SK_MZ[3] + P[17][17]*SK_MZ[1] + P[17][15]*SK_MZ[5] - P[17][16]*SK_MZ[4]);
-            Kfusion[18] = SK_MZ[0]*(P[18][20] + P[18][0]*SH_MAG[1] + P[18][3]*SH_MAG[0] - P[18][1]*SK_MZ[2] + P[18][2]*SK_MZ[3] + P[18][17]*SK_MZ[1] + P[18][15]*SK_MZ[5] - P[18][16]*SK_MZ[4]);
-            Kfusion[19] = SK_MZ[0]*(P[19][20] + P[19][0]*SH_MAG[1] + P[19][3]*SH_MAG[0] - P[19][1]*SK_MZ[2] + P[19][2]*SK_MZ[3] + P[19][17]*SK_MZ[1] + P[19][15]*SK_MZ[5] - P[19][16]*SK_MZ[4]);
-            Kfusion[20] = SK_MZ[0]*(P[20][20] + P[20][0]*SH_MAG[1] + P[20][3]*SH_MAG[0] - P[20][1]*SK_MZ[2] + P[20][2]*SK_MZ[3] + P[20][17]*SK_MZ[1] + P[20][15]*SK_MZ[5] - P[20][16]*SK_MZ[4]);
-            varInnovMag[2] = 1.0f/SK_MZ[0];
-            innovMag[2] = MagPred[2] - magData.z;
-
-        }
-
-        // Check the innovation for consistency and don't fuse if > 5Sigma
-        if ((innovMag[obsIndex]*innovMag[obsIndex]/varInnovMag[obsIndex]) < 25.0)
-        {
-            // correct the state vector
-            for (uint8_t j= 0; j<=indexLimit; j++)
-            {
-                states[j] = states[j] - Kfusion[j] * innovMag[obsIndex];
-            }
-            // normalise the quaternion states
-            float quatMag = sqrt(states[0]*states[0] + states[1]*states[1] + states[2]*states[2] + states[3]*states[3]);
-            if (quatMag > 1e-12)
-            {
-                for (uint8_t j= 0; j<=3; j++)
-                {
-                    float quatMagInv = 1.0f/quatMag;
-                    states[j] = states[j] * quatMagInv;
-                }
-            }
-            // correct the covariance P = (I - K*H)*P
-            // take advantage of the empty columns in KH to reduce the
-            // number of operations
-            for (uint8_t i = 0; i<=indexLimit; i++)
-            {
-                for (uint8_t j = 0; j<=3; j++)
-                {
-                    KH[i][j] = Kfusion[i] * H_MAG[j];
-                }
-                for (uint8_t j = 4; j<=17; j++) KH[i][j] = 0.0f;
-                if (!onGround)
-                {
-                    for (uint8_t j = 15; j<=20; j++)
-                    {
-                        KH[i][j] = Kfusion[i] * H_MAG[j];
-                    }
-                }
-                else
-                {
-                    for (uint8_t j = 15; j<=20; j++)
-                    {
-                        KH[i][j] = 0.0f;
-                    }
-                }
-            }
-            for (uint8_t i = 0; i<=indexLimit; i++)
-            {
-                for (uint8_t j = 0; j<=indexLimit; j++)
-                {
-                    KHP[i][j] = 0.0f;
-                    for (uint8_t k = 0; k<=3; k++)
-                    {
-                        KHP[i][j] = KHP[i][j] + KH[i][k] * P[k][j];
-                    }
-                    if (!onGround)
-                    {
-                        for (uint8_t k = 15; k<=20; k++)
-                        {
-                            KHP[i][j] = KHP[i][j] + KH[i][k] * P[k][j];
-                        }
-                    }
-                }
-            }
-        }
-        for (uint8_t i = 0; i<=indexLimit; i++)
-        {
-            for (uint8_t j = 0; j<=indexLimit; j++)
-            {
-                P[i][j] = P[i][j] - KHP[i][j];
-            }
-        }
-    }
-    obsIndex = obsIndex + 1;
-
-    ForceSymmetry();
-    ConstrainVariances();
-}
-
-void AttPosEKF::FuseAirspeed()
-{
-    float vn;
-    float ve;
-    float vd;
-    float vwn;
-    float vwe;
-    const float R_TAS = 2.0f;
-    float SH_TAS[3];
-    float Kfusion[21];
-    float VtasPred;
-
-    // Copy required states to local variable names
-    vn = statesAtVtasMeasTime[4];
-    ve = statesAtVtasMeasTime[5];
-    vd = statesAtVtasMeasTime[6];
-    vwn = statesAtVtasMeasTime[13];
-    vwe = statesAtVtasMeasTime[14];
-
-    // Need to check that it is flying before fusing airspeed data
-    // Calculate the predicted airspeed
-    VtasPred = sqrtf((ve - vwe)*(ve - vwe) + (vn - vwn)*(vn - vwn) + vd*vd);
-    // Perform fusion of True Airspeed measurement
-    if (useAirspeed && fuseVtasData && (VtasPred > 1.0f) && (VtasMeas > 8.0f))
-    {
-        // Calculate observation jacobians
-        SH_TAS[0] = 1/(sqrt(sq(ve - vwe) + sq(vn - vwn) + sq(vd)));
-        SH_TAS[1] = (SH_TAS[0]*(2.0f*ve - 2*vwe))/2.0f;
-        SH_TAS[2] = (SH_TAS[0]*(2.0f*vn - 2*vwn))/2.0f;
-        
-        float H_TAS[21];
-        for (uint8_t i=0; i<=20; i++) H_TAS[i] = 0.0f;
-        H_TAS[4] = SH_TAS[2];
-        H_TAS[5] = SH_TAS[1];
-        H_TAS[6] = vd*SH_TAS[0];
-        H_TAS[13] = -SH_TAS[2];
-        H_TAS[14] = -SH_TAS[1];
-
-        // Calculate Kalman gains
-        float SK_TAS = 1.0f/(R_TAS + SH_TAS[2]*(P[4][4]*SH_TAS[2] + P[5][4]*SH_TAS[1] - P[13][4]*SH_TAS[2] - P[14][4]*SH_TAS[1] + P[6][4]*vd*SH_TAS[0]) + SH_TAS[1]*(P[4][5]*SH_TAS[2] + P[5][5]*SH_TAS[1] - P[13][5]*SH_TAS[2] - P[14][5]*SH_TAS[1] + P[6][5]*vd*SH_TAS[0]) - SH_TAS[2]*(P[4][13]*SH_TAS[2] + P[5][13]*SH_TAS[1] - P[13][13]*SH_TAS[2] - P[14][13]*SH_TAS[1] + P[6][13]*vd*SH_TAS[0]) - SH_TAS[1]*(P[4][14]*SH_TAS[2] + P[5][14]*SH_TAS[1] - P[13][14]*SH_TAS[2] - P[14][14]*SH_TAS[1] + P[6][14]*vd*SH_TAS[0]) + vd*SH_TAS[0]*(P[4][6]*SH_TAS[2] + P[5][6]*SH_TAS[1] - P[13][6]*SH_TAS[2] - P[14][6]*SH_TAS[1] + P[6][6]*vd*SH_TAS[0]));
-        Kfusion[0] = SK_TAS*(P[0][4]*SH_TAS[2] - P[0][13]*SH_TAS[2] + P[0][5]*SH_TAS[1] - P[0][14]*SH_TAS[1] + P[0][6]*vd*SH_TAS[0]);
-        Kfusion[1] = SK_TAS*(P[1][4]*SH_TAS[2] - P[1][13]*SH_TAS[2] + P[1][5]*SH_TAS[1] - P[1][14]*SH_TAS[1] + P[1][6]*vd*SH_TAS[0]);
-        Kfusion[2] = SK_TAS*(P[2][4]*SH_TAS[2] - P[2][13]*SH_TAS[2] + P[2][5]*SH_TAS[1] - P[2][14]*SH_TAS[1] + P[2][6]*vd*SH_TAS[0]);
-        Kfusion[3] = SK_TAS*(P[3][4]*SH_TAS[2] - P[3][13]*SH_TAS[2] + P[3][5]*SH_TAS[1] - P[3][14]*SH_TAS[1] + P[3][6]*vd*SH_TAS[0]);
-        Kfusion[4] = SK_TAS*(P[4][4]*SH_TAS[2] - P[4][13]*SH_TAS[2] + P[4][5]*SH_TAS[1] - P[4][14]*SH_TAS[1] + P[4][6]*vd*SH_TAS[0]);
-        Kfusion[5] = SK_TAS*(P[5][4]*SH_TAS[2] - P[5][13]*SH_TAS[2] + P[5][5]*SH_TAS[1] - P[5][14]*SH_TAS[1] + P[5][6]*vd*SH_TAS[0]);
-        Kfusion[6] = SK_TAS*(P[6][4]*SH_TAS[2] - P[6][13]*SH_TAS[2] + P[6][5]*SH_TAS[1] - P[6][14]*SH_TAS[1] + P[6][6]*vd*SH_TAS[0]);
-        Kfusion[7] = SK_TAS*(P[7][4]*SH_TAS[2] - P[7][13]*SH_TAS[2] + P[7][5]*SH_TAS[1] - P[7][14]*SH_TAS[1] + P[7][6]*vd*SH_TAS[0]);
-        Kfusion[8] = SK_TAS*(P[8][4]*SH_TAS[2] - P[8][13]*SH_TAS[2] + P[8][5]*SH_TAS[1] - P[8][14]*SH_TAS[1] + P[8][6]*vd*SH_TAS[0]);
-        Kfusion[9] = SK_TAS*(P[9][4]*SH_TAS[2] - P[9][13]*SH_TAS[2] + P[9][5]*SH_TAS[1] - P[9][14]*SH_TAS[1] + P[9][6]*vd*SH_TAS[0]);
-        Kfusion[10] = SK_TAS*(P[10][4]*SH_TAS[2] - P[10][13]*SH_TAS[2] + P[10][5]*SH_TAS[1] - P[10][14]*SH_TAS[1] + P[10][6]*vd*SH_TAS[0]);
-        Kfusion[11] = SK_TAS*(P[11][4]*SH_TAS[2] - P[11][13]*SH_TAS[2] + P[11][5]*SH_TAS[1] - P[11][14]*SH_TAS[1] + P[11][6]*vd*SH_TAS[0]);
-        Kfusion[12] = SK_TAS*(P[12][4]*SH_TAS[2] - P[12][13]*SH_TAS[2] + P[12][5]*SH_TAS[1] - P[12][14]*SH_TAS[1] + P[12][6]*vd*SH_TAS[0]);
-        Kfusion[13] = SK_TAS*(P[13][4]*SH_TAS[2] - P[13][13]*SH_TAS[2] + P[13][5]*SH_TAS[1] - P[13][14]*SH_TAS[1] + P[13][6]*vd*SH_TAS[0]);
-        Kfusion[14] = SK_TAS*(P[14][4]*SH_TAS[2] - P[14][13]*SH_TAS[2] + P[14][5]*SH_TAS[1] - P[14][14]*SH_TAS[1] + P[14][6]*vd*SH_TAS[0]);
-        Kfusion[15] = SK_TAS*(P[15][4]*SH_TAS[2] - P[15][13]*SH_TAS[2] + P[15][5]*SH_TAS[1] - P[15][14]*SH_TAS[1] + P[15][6]*vd*SH_TAS[0]);
-        Kfusion[16] = SK_TAS*(P[16][4]*SH_TAS[2] - P[16][13]*SH_TAS[2] + P[16][5]*SH_TAS[1] - P[16][14]*SH_TAS[1] + P[16][6]*vd*SH_TAS[0]);
-        Kfusion[17] = SK_TAS*(P[17][4]*SH_TAS[2] - P[17][13]*SH_TAS[2] + P[17][5]*SH_TAS[1] - P[17][14]*SH_TAS[1] + P[17][6]*vd*SH_TAS[0]);
-        Kfusion[18] = SK_TAS*(P[18][4]*SH_TAS[2] - P[18][13]*SH_TAS[2] + P[18][5]*SH_TAS[1] - P[18][14]*SH_TAS[1] + P[18][6]*vd*SH_TAS[0]);
-        Kfusion[19] = SK_TAS*(P[19][4]*SH_TAS[2] - P[19][13]*SH_TAS[2] + P[19][5]*SH_TAS[1] - P[19][14]*SH_TAS[1] + P[19][6]*vd*SH_TAS[0]);
-        Kfusion[20] = SK_TAS*(P[20][4]*SH_TAS[2] - P[20][13]*SH_TAS[2] + P[20][5]*SH_TAS[1] - P[20][14]*SH_TAS[1] + P[20][6]*vd*SH_TAS[0]);
-        varInnovVtas = 1.0f/SK_TAS;
-
-        // Calculate the measurement innovation
-        innovVtas = VtasPred - VtasMeas;
-        // Check the innovation for consistency and don't fuse if > 5Sigma
-        if ((innovVtas*innovVtas*SK_TAS) < 25.0)
-        {
-            // correct the state vector
-            for (uint8_t j=0; j<=20; j++)
-            {
-                states[j] = states[j] - Kfusion[j] * innovVtas;
-            }
-            // normalise the quaternion states
-            float quatMag = sqrt(states[0]*states[0] + states[1]*states[1] + states[2]*states[2] + states[3]*states[3]);
-            if (quatMag > 1e-12f)
-            {
-                for (uint8_t j= 0; j<=3; j++)
-                {
-                    float quatMagInv = 1.0f/quatMag;
-                    states[j] = states[j] * quatMagInv;
-                }
-            }
-            // correct the covariance P = (I - K*H)*P
-            // take advantage of the empty columns in H to reduce the
-            // number of operations
-            for (uint8_t i = 0; i<=20; i++)
-            {
-                for (uint8_t j = 0; j<=3; j++) KH[i][j] = 0.0;
-                for (uint8_t j = 4; j<=6; j++)
-                {
-                    KH[i][j] = Kfusion[i] * H_TAS[j];
-                }
-                for (uint8_t j = 7; j<=12; j++) KH[i][j] = 0.0;
-                for (uint8_t j = 13; j<=14; j++)
-                {
-                    KH[i][j] = Kfusion[i] * H_TAS[j];
-                }
-                for (uint8_t j = 15; j<=20; j++) KH[i][j] = 0.0;
-            }
-            for (uint8_t i = 0; i<=20; i++)
-            {
-                for (uint8_t j = 0; j<=20; j++)
-                {
-                    KHP[i][j] = 0.0;
-                    for (uint8_t k = 4; k<=6; k++)
-                    {
-                        KHP[i][j] = KHP[i][j] + KH[i][k] * P[k][j];
-                    }
-                    for (uint8_t k = 13; k<=14; k++)
-                    {
-                        KHP[i][j] = KHP[i][j] + KH[i][k] * P[k][j];
-                    }
-                }
-            }
-            for (uint8_t i = 0; i<=20; i++)
-            {
-                for (uint8_t j = 0; j<=20; j++)
-                {
-                    P[i][j] = P[i][j] - KHP[i][j];
-                }
-            }
-        }
-    }
-
-    ForceSymmetry();
-    ConstrainVariances();
-}
-
-void AttPosEKF::zeroRows(float (&covMat)[n_states][n_states], uint8_t first, uint8_t last)
-{
-    uint8_t row;
-    uint8_t col;
-    for (row=first; row<=last; row++)
-    {
-        for (col=0; col<n_states; col++)
-        {
-            covMat[row][col] = 0.0;
-        }
-    }
-}
-
-void AttPosEKF::zeroCols(float (&covMat)[n_states][n_states], uint8_t first, uint8_t last)
-{
-    uint8_t row;
-    uint8_t col;
-    for (col=first; col<=last; col++)
-    {
-        for (row=0; row < n_states; row++)
-        {
-            covMat[row][col] = 0.0;
-        }
-    }
-}
-
-float AttPosEKF::sq(float valIn)
-{
-    return valIn*valIn;
-}
-
-// Store states in a history array along with time stamp
-void AttPosEKF::StoreStates(uint64_t timestamp_ms)
-{
-    for (unsigned i=0; i<n_states; i++)
-        storedStates[i][storeIndex] = states[i];
-    statetimeStamp[storeIndex] = timestamp_ms;
-    storeIndex++;
-    if (storeIndex == data_buffer_size)
-        storeIndex = 0;
-}
-
-void AttPosEKF::ResetStoredStates()
-{
-    // reset all stored states
-    memset(&storedStates[0][0], 0, sizeof(storedStates));
-    memset(&statetimeStamp[0], 0, sizeof(statetimeStamp));
-
-    // reset store index to first
-    storeIndex = 0;
-
-    // overwrite all existing states
-    for (unsigned i = 0; i < n_states; i++) {
-        storedStates[i][storeIndex] = states[i];
-    }
-
-    statetimeStamp[storeIndex] = millis();
-
-    // increment to next storage index
-    storeIndex++;
-}
-
-// Output the state vector stored at the time that best matches that specified by msec
-int AttPosEKF::RecallStates(float statesForFusion[n_states], uint64_t msec)
-{
-    int ret = 0;
-
-    // int64_t bestTimeDelta = 200;
-    // unsigned bestStoreIndex = 0;
-    // for (unsigned storeIndex = 0; storeIndex < data_buffer_size; storeIndex++)
-    // {
-    //     // The time delta can also end up as negative number,
-    //     // since we might compare future to past or past to future
-    //     // therefore cast to int64.
-    //     int64_t timeDelta = (int64_t)msec - (int64_t)statetimeStamp[storeIndex];
-    //     if (timeDelta < 0) {
-    //         timeDelta = -timeDelta;
-    //     }
-
-    //     if (timeDelta < bestTimeDelta)
-    //     {
-    //         bestStoreIndex = storeIndex;
-    //         bestTimeDelta = timeDelta;
-    //     }
-    // }
-    // if (bestTimeDelta < 200) // only output stored state if < 200 msec retrieval error
-    // {
-    //     for (uint8_t i=0; i < n_states; i++) {
-    //         if (isfinite(storedStates[i][bestStoreIndex])) {
-    //             statesForFusion[i] = storedStates[i][bestStoreIndex];
-    //         } else if (isfinite(states[i])) {
-    //             statesForFusion[i] = states[i];
-    //         } else {
-    //             // There is not much we can do here, except reporting the error we just
-    //             // found.
-    //             ret++;
-    //         }
-    // }
-    // else // otherwise output current state
-    // {
-        for (uint8_t i=0; i < n_states; i++) {
-            if (isfinite(states[i])) {
-                statesForFusion[i] = states[i];
-            } else {
-                ret++;
-            }
-        }
-    // }
-
-    return ret;
-}
-
-void AttPosEKF::quat2Tnb(Mat3f &Tnb, const float (&quat)[4])
-{
-    // Calculate the nav to body cosine matrix
-    float q00 = sq(quat[0]);
-    float q11 = sq(quat[1]);
-    float q22 = sq(quat[2]);
-    float q33 = sq(quat[3]);
-    float q01 =  quat[0]*quat[1];
-    float q02 =  quat[0]*quat[2];
-    float q03 =  quat[0]*quat[3];
-    float q12 =  quat[1]*quat[2];
-    float q13 =  quat[1]*quat[3];
-    float q23 =  quat[2]*quat[3];
-
-    Tnb.x.x = q00 + q11 - q22 - q33;
-    Tnb.y.y = q00 - q11 + q22 - q33;
-    Tnb.z.z = q00 - q11 - q22 + q33;
-    Tnb.y.x = 2*(q12 - q03);
-    Tnb.z.x = 2*(q13 + q02);
-    Tnb.x.y = 2*(q12 + q03);
-    Tnb.z.y = 2*(q23 - q01);
-    Tnb.x.z = 2*(q13 - q02);
-    Tnb.y.z = 2*(q23 + q01);
-}
-
-void AttPosEKF::quat2Tbn(Mat3f &Tbn, const float (&quat)[4])
-{
-    // Calculate the body to nav cosine matrix
-    float q00 = sq(quat[0]);
-    float q11 = sq(quat[1]);
-    float q22 = sq(quat[2]);
-    float q33 = sq(quat[3]);
-    float q01 =  quat[0]*quat[1];
-    float q02 =  quat[0]*quat[2];
-    float q03 =  quat[0]*quat[3];
-    float q12 =  quat[1]*quat[2];
-    float q13 =  quat[1]*quat[3];
-    float q23 =  quat[2]*quat[3];
-
-    Tbn.x.x = q00 + q11 - q22 - q33;
-    Tbn.y.y = q00 - q11 + q22 - q33;
-    Tbn.z.z = q00 - q11 - q22 + q33;
-    Tbn.x.y = 2*(q12 - q03);
-    Tbn.x.z = 2*(q13 + q02);
-    Tbn.y.x = 2*(q12 + q03);
-    Tbn.y.z = 2*(q23 - q01);
-    Tbn.z.x = 2*(q13 - q02);
-    Tbn.z.y = 2*(q23 + q01);
-}
-
-void AttPosEKF::eul2quat(float (&quat)[4], const float (&eul)[3])
-{
-    float u1 = cos(0.5f*eul[0]);
-    float u2 = cos(0.5f*eul[1]);
-    float u3 = cos(0.5f*eul[2]);
-    float u4 = sin(0.5f*eul[0]);
-    float u5 = sin(0.5f*eul[1]);
-    float u6 = sin(0.5f*eul[2]);
-    quat[0] = u1*u2*u3+u4*u5*u6;
-    quat[1] = u4*u2*u3-u1*u5*u6;
-    quat[2] = u1*u5*u3+u4*u2*u6;
-    quat[3] = u1*u2*u6-u4*u5*u3;
-}
-
-void AttPosEKF::quat2eul(float (&y)[3], const float (&u)[4])
-{
-    y[0] = atan2f((2.0f*(u[2]*u[3]+u[0]*u[1])) , (u[0]*u[0]-u[1]*u[1]-u[2]*u[2]+u[3]*u[3]));
-    y[1] = -asinf(2.0f*(u[1]*u[3]-u[0]*u[2]));
-    y[2] = atan2f((2.0f*(u[1]*u[2]+u[0]*u[3])) , (u[0]*u[0]+u[1]*u[1]-u[2]*u[2]-u[3]*u[3]));
-}
-
-void AttPosEKF::calcvelNED(float (&velNED)[3], float gpsCourse, float gpsGndSpd, float gpsVelD)
-{
-    velNED[0] = gpsGndSpd*cosf(gpsCourse);
-    velNED[1] = gpsGndSpd*sinf(gpsCourse);
-    velNED[2] = gpsVelD;
-}
-
-void AttPosEKF::calcposNED(float (&posNED)[3], float lat, float lon, float hgt, float latRef, float lonRef, float hgtRef)
-{
-    posNED[0] = earthRadius * (lat - latRef);
-    posNED[1] = earthRadius * cos(latRef) * (lon - lonRef);
-    posNED[2] = -(hgt - hgtRef);
-}
-
-void AttPosEKF::calcLLH(float (&posNED)[3], float lat, float lon, float hgt, float latRef, float lonRef, float hgtRef)
-{
-    lat = latRef + posNED[0] * earthRadiusInv;
-    lon = lonRef + posNED[1] * earthRadiusInv / cos(latRef);
-    hgt = hgtRef - posNED[2];
-}
-
-void AttPosEKF::OnGroundCheck()
-{
-    onGround = (((sq(velNED[0]) + sq(velNED[1]) + sq(velNED[2])) < 4.0f) && (VtasMeas < 8.0f));
-    if (staticMode) {
-        staticMode = !(GPSstatus > GPS_FIX_2D);
-    }
-}
-
-void AttPosEKF::calcEarthRateNED(Vector3f &omega, float latitude)
-{
-    //Define Earth rotation vector in the NED navigation frame
-    omega.x  = earthRate*cosf(latitude);
-    omega.y  = 0.0f;
-    omega.z  = -earthRate*sinf(latitude);
-}
-
-void AttPosEKF::CovarianceInit()
-{
-    // Calculate the initial covariance matrix P
-    P[0][0]   = 0.25f * sq(1.0f*deg2rad);
-    P[1][1]   = 0.25f * sq(1.0f*deg2rad);
-    P[2][2]   = 0.25f * sq(1.0f*deg2rad);
-    P[3][3]   = 0.25f * sq(10.0f*deg2rad);
-    P[4][4]   = sq(0.7);
-    P[5][5]   = P[4][4];
-    P[6][6]   = sq(0.7);
-    P[7][7]   = sq(15.0);
-    P[8][8]   = P[7][7];
-    P[9][9]   = sq(5.0);
-    P[10][10] = sq(0.1*deg2rad*dtIMU);
-    P[11][11] = P[10][10];
-    P[12][12] = P[10][10];
-    P[13][13] = sq(8.0f);
-    P[14][4]  = P[13][13];
-    P[15][15] = sq(0.02f);
-    P[16][16] = P[15][15];
-    P[17][17] = P[15][15];
-    P[18][18] = sq(0.02f);
-    P[19][19] = P[18][18];
-    P[20][20] = P[18][18];
-}
-
-float AttPosEKF::ConstrainFloat(float val, float min, float max)
-{
-    return (val > max) ? max : ((val < min) ? min : val);
-}
-
-void AttPosEKF::ConstrainVariances()
-{
-    if (!numericalProtection) {
-        return;
-    }
-
-    // State vector:
-    // 0-3: quaternions (q0, q1, q2, q3)
-    // 4-6: Velocity - m/sec (North, East, Down)
-    // 7-9: Position - m (North, East, Down)
-    // 10-12: Delta Angle bias - rad (X,Y,Z)
-    // 13-14: Wind Vector  - m/sec (North,East)
-    // 15-17: Earth Magnetic Field Vector - gauss (North, East, Down)
-    // 18-20: Body Magnetic Field Vector - gauss (X,Y,Z)
-
-    // Constrain quaternion variances
-    for (unsigned i = 0; i < 4; i++) {
-        P[i][i] = ConstrainFloat(P[i][i], 0.0f, 1.0f);
-    }
-
-    // Constrain velocitie variances
-    for (unsigned i = 4; i < 7; i++) {
-        P[i][i] = ConstrainFloat(P[i][i], 0.0f, 1.0e3f);
-    }
-
-    // Constrain position variances
-    for (unsigned i = 7; i < 10; i++) {
-        P[i][i] = ConstrainFloat(P[i][i], 0.0f, 1.0e6f);
-    }
-
-    // Angle bias variances
-    for (unsigned i = 10; i < 13; i++) {
-        P[i][i] = ConstrainFloat(P[i][i], 0.0f, sq(0.175f * dtIMU));
-    }
-
-    // Wind velocity variances
-    for (unsigned i = 13; i < 15; i++) {
-        P[i][i] = ConstrainFloat(P[i][i], 0.0f, 1.0e3f);
-    }
-
-    // Earth magnetic field variances
-    for (unsigned i = 15; i < 18; i++) {
-        P[i][i] = ConstrainFloat(P[i][i], 0.0f, 1.0f);
-    }
-
-    // Body magnetic field variances
-    for (unsigned i = 18; i < 21; i++) {
-        P[i][i] = ConstrainFloat(P[i][i], 0.0f, 1.0f);
-    }
-
-}
-
-void AttPosEKF::ConstrainStates()
-{
-    if (!numericalProtection) {
-        return;
-    }
-
-    // State vector:
-    // 0-3: quaternions (q0, q1, q2, q3)
-    // 4-6: Velocity - m/sec (North, East, Down)
-    // 7-9: Position - m (North, East, Down)
-    // 10-12: Delta Angle bias - rad (X,Y,Z)
-    // 13-14: Wind Vector  - m/sec (North,East)
-    // 15-17: Earth Magnetic Field Vector - gauss (North, East, Down)
-    // 18-20: Body Magnetic Field Vector - gauss (X,Y,Z)
-
-
-    // Constrain quaternion
-    for (unsigned i = 0; i < 4; i++) {
-        states[i] = ConstrainFloat(states[i], -1.0f, 1.0f);
-    }
-
-    // Constrain velocities to what GPS can do for us
-    for (unsigned i = 4; i < 7; i++) {
-        states[i] = ConstrainFloat(states[i], -5.0e2f, 5.0e2f);
-    }
-
-    // Constrain position to a reasonable vehicle range (in meters)
-    for (unsigned i = 7; i < 9; i++) {
-        states[i] = ConstrainFloat(states[i], -1.0e6f, 1.0e6f);
-    }
-
-    // Constrain altitude
-    states[9] = ConstrainFloat(states[9], -4.0e4f, 1.0e4f);
-
-    // Angle bias limit - set to 8 degrees / sec
-    for (unsigned i = 10; i < 13; i++) {
-        states[i] = ConstrainFloat(states[i], -0.12f * dtIMU, 0.12f * dtIMU);
-    }
-
-    // Wind velocity limits - assume 120 m/s max velocity
-    for (unsigned i = 13; i < 15; i++) {
-        states[i] = ConstrainFloat(states[i], -120.0f, 120.0f);
-    }
-
-    // Earth magnetic field limits (in Gauss)
-    for (unsigned i = 15; i < 18; i++) {
-        states[i] = ConstrainFloat(states[i], -1.0f, 1.0f);
-    }
-
-    // Body magnetic field variances (in Gauss).
-    // the max offset should be in this range.
-    for (unsigned i = 18; i < 21; i++) {
-        states[i] = ConstrainFloat(states[i], -0.5f, 0.5f);
-    }
-
-}
-
-void AttPosEKF::ForceSymmetry()
-{
-    if (!numericalProtection) {
-        return;
-    }
-
-    // Force symmetry on the covariance matrix to prevent ill-conditioning
-    // of the matrix which would cause the filter to blow-up
-    for (unsigned i = 1; i < n_states; i++)
-    {
-        for (uint8_t j = 0; j < i; j++)
-        {
-            P[i][j] = 0.5f * (P[i][j] + P[j][i]);
-            P[j][i] = P[i][j];
-        }
-    }
-}
-
-bool AttPosEKF::FilterHealthy()
-{
-    if (!statesInitialised) {
-        return false;
-    }
-
-    // XXX Check state vector for NaNs and ill-conditioning
-
-    // Check if any of the major inputs timed out
-    if (current_ekf_state.posTimeout || current_ekf_state.velTimeout || current_ekf_state.hgtTimeout) {
-        return false;
-    }
-
-    // Nothing fired, return ok.
-    return true;
-}
-
-/**
- * Reset the filter position states
- *
- * This resets the position to the last GPS measurement
- * or to zero in case of static position.
- */
-void AttPosEKF::ResetPosition(void)
-{
-    if (staticMode) {
-        states[7] = 0;
-        states[8] = 0;
-    } else if (GPSstatus >= GPS_FIX_3D) {
-
-        // reset the states from the GPS measurements
-        states[7] = posNE[0];
-        states[8] = posNE[1];
-    }
-}
-
-/**
- * Reset the height state.
- *
- * This resets the height state with the last altitude measurements
- */
-void AttPosEKF::ResetHeight(void)
-{
-    // write to the state vector
-    states[9]   = -hgtMea;
-}
-
-/**
- * Reset the velocity state.
- */
-void AttPosEKF::ResetVelocity(void)
-{
-    if (staticMode) {
-        states[4] = 0.0f;
-        states[5] = 0.0f;
-        states[6] = 0.0f;
-    } else if (GPSstatus >= GPS_FIX_3D) {
-
-        states[4]  = velNED[0]; // north velocity from last reading
-        states[5]  = velNED[1]; // east velocity from last reading
-        states[6]  = velNED[2]; // down velocity from last reading
-    }
-}
-
-
-void AttPosEKF::FillErrorReport(struct ekf_status_report *err)
-{
-    for (int i = 0; i < n_states; i++)
-    {
-        err->states[i] = states[i];
-    }
-
-    err->velHealth = current_ekf_state.velHealth;
-    err->posHealth = current_ekf_state.posHealth;
-    err->hgtHealth = current_ekf_state.hgtHealth;
-    err->velTimeout = current_ekf_state.velTimeout;
-    err->posTimeout = current_ekf_state.posTimeout;
-    err->hgtTimeout = current_ekf_state.hgtTimeout;
-}
-
-bool AttPosEKF::StatesNaN(struct ekf_status_report *err_report) {
-    bool err = false;
-
-    // check all states and covariance matrices
-    for (unsigned i = 0; i < n_states; i++) {
-        for (unsigned j = 0; j < n_states; j++) {
-            if (!isfinite(KH[i][j])) {
-
-                err_report->covarianceNaN = true;
-                err = true;
-            } //  intermediate result used for covariance updates
-            if (!isfinite(KHP[i][j])) {
-
-                err_report->covarianceNaN = true;
-                err = true;
-            } // intermediate result used for covariance updates
-            if (!isfinite(P[i][j])) {
-
-                err_report->covarianceNaN = true;
-                err = true;
-            } // covariance matrix
-        }
-
-        if (!isfinite(Kfusion[i])) {
-
-            err_report->kalmanGainsNaN = true;
-            err = true;
-        } // Kalman gains
-
-        if (!isfinite(states[i])) {
-
-            err_report->statesNaN = true;
-            err = true;
-        } // state matrix
-    }
-
-    if (err) {
-        FillErrorReport(err_report);
-    }
-
-    return err;
-
-}
-
-/**
- * Check the filter inputs and bound its operational state
- *
- * This check will reset the filter states if required
- * due to a failure of consistency or timeout checks.
- * it should be run after the measurement data has been
- * updated, but before any of the fusion steps are
- * executed.
- */
-int AttPosEKF::CheckAndBound()
-{
-
-    // Store the old filter state
-    bool currStaticMode = staticMode;
-
-    // Reset the filter if the states went NaN
-    if (StatesNaN(&last_ekf_error)) {
-
-        InitializeDynamic(velNED);
-
-        return 1;
-    }
-
-    // Reset the filter if the IMU data is too old
-    if (dtIMU > 0.2f) {
-
-        ResetVelocity();
-        ResetPosition();
-        ResetHeight();
-        ResetStoredStates();
-
-        // that's all we can do here, return
-        return 2;
-    }
-
-    // Check if we're on ground - this also sets static mode.
-    OnGroundCheck();
-
-    // Check if we switched between states
-    if (currStaticMode != staticMode) {
-        ResetVelocity();
-        ResetPosition();
-        ResetHeight();
-        ResetStoredStates();
-
-        return 3;
-    }
-
-    return 0;
-}
-
-void AttPosEKF::AttitudeInit(float ax, float ay, float az, float mx, float my, float mz, float *initQuat)
-{
-    float initialRoll, initialPitch;
-    float cosRoll, sinRoll, cosPitch, sinPitch;
-    float magX, magY;
-    float initialHdg, cosHeading, sinHeading;
-
-    initialRoll = atan2(-ay, -az);
-    initialPitch = atan2(ax, -az);
-
-    cosRoll = cosf(initialRoll);
-    sinRoll = sinf(initialRoll);
-    cosPitch = cosf(initialPitch);
-    sinPitch = sinf(initialPitch);
-
-    magX = mx * cosPitch + my * sinRoll * sinPitch + mz * cosRoll * sinPitch;
-
-    magY = my * cosRoll - mz * sinRoll;
-
-    initialHdg = atan2f(-magY, magX);
-
-    cosRoll = cosf(initialRoll * 0.5f);
-    sinRoll = sinf(initialRoll * 0.5f);
-
-    cosPitch = cosf(initialPitch * 0.5f);
-    sinPitch = sinf(initialPitch * 0.5f);
-
-    cosHeading = cosf(initialHdg * 0.5f);
-    sinHeading = sinf(initialHdg * 0.5f);
-
-    initQuat[0] = cosRoll * cosPitch * cosHeading + sinRoll * sinPitch * sinHeading;
-    initQuat[1] = sinRoll * cosPitch * cosHeading - cosRoll * sinPitch * sinHeading;
-    initQuat[2] = cosRoll * sinPitch * cosHeading + sinRoll * cosPitch * sinHeading;
-    initQuat[3] = cosRoll * cosPitch * sinHeading - sinRoll * sinPitch * cosHeading;
-}
-
-void AttPosEKF::InitializeDynamic(float (&initvelNED)[3])
-{
-
-    // Clear the init flag
-    statesInitialised = false;
-
-    ZeroVariables();
-
-    // Calculate initial filter quaternion states from raw measurements
-    float initQuat[4];
-    Vector3f initMagXYZ;
-    initMagXYZ   = magData - magBias;
-    AttitudeInit(accel.x, accel.y, accel.z, initMagXYZ.x, initMagXYZ.y, initMagXYZ.z, initQuat);
-
-    // Calculate initial Tbn matrix and rotate Mag measurements into NED
-    // to set initial NED magnetic field states
-    Mat3f DCM;
-    quat2Tbn(DCM, initQuat);
-    Vector3f initMagNED;
-    initMagXYZ   = magData - magBias;
-    initMagNED.x = DCM.x.x*initMagXYZ.x + DCM.x.y*initMagXYZ.y + DCM.x.z*initMagXYZ.z;
-    initMagNED.y = DCM.y.x*initMagXYZ.x + DCM.y.y*initMagXYZ.y + DCM.y.z*initMagXYZ.z;
-    initMagNED.z = DCM.z.x*initMagXYZ.x + DCM.z.y*initMagXYZ.y + DCM.z.z*initMagXYZ.z;
-
-
-
-    // write to state vector
-    for (uint8_t j=0; j<=3; j++) states[j] = initQuat[j]; // quaternions
-    for (uint8_t j=0; j<=2; j++) states[j+4] = initvelNED[j]; // velocities
-    for (uint8_t j=0; j<=7; j++) states[j+7] = 0.0f; // positiions, dAngBias, windVel
-    states[15] = initMagNED.x; // Magnetic Field North
-    states[16] = initMagNED.y; // Magnetic Field East
-    states[17] = initMagNED.z; // Magnetic Field Down
-    states[18] = magBias.x; // Magnetic Field Bias X
-    states[19] = magBias.y; // Magnetic Field Bias Y
-    states[20] = magBias.z; // Magnetic Field Bias Z
-
-    statesInitialised = true;
-
-    // initialise the covariance matrix
-    CovarianceInit();
-
-    //Define Earth rotation vector in the NED navigation frame
-    calcEarthRateNED(earthRateNED, latRef);
-
-    //Initialise summed variables used by covariance prediction
-    summedDelAng.x = 0.0f;
-    summedDelAng.y = 0.0f;
-    summedDelAng.z = 0.0f;
-    summedDelVel.x = 0.0f;
-    summedDelVel.y = 0.0f;
-    summedDelVel.z = 0.0f;
-}
-
-void AttPosEKF::InitialiseFilter(float (&initvelNED)[3])
-{
-    //store initial lat,long and height
-    latRef = gpsLat;
-    lonRef = gpsLon;
-    hgtRef = gpsHgt;
-
-    memset(&last_ekf_error, 0, sizeof(last_ekf_error));
-
-    InitializeDynamic(initvelNED);
-}
-
-void AttPosEKF::ZeroVariables()
-{
-    // Do the data structure init
-    for (unsigned i = 0; i < n_states; i++) {
-        for (unsigned j = 0; j < n_states; j++) {
-            KH[i][j] = 0.0f; //  intermediate result used for covariance updates
-            KHP[i][j] = 0.0f; // intermediate result used for covariance updates
-            P[i][j] = 0.0f; // covariance matrix
-        }
-
-        Kfusion[i] = 0.0f; // Kalman gains
-        states[i] = 0.0f; // state matrix
-    }
-
-    for (unsigned i = 0; i < data_buffer_size; i++) {
-
-        for (unsigned j = 0; j < n_states; j++) {
-            storedStates[j][i] = 0.0f;
-        }
-
-        statetimeStamp[i] = 0;
-    }
-
-    memset(&current_ekf_state, 0, sizeof(current_ekf_state));
-}
-
-void AttPosEKF::GetFilterState(struct ekf_status_report *state)
-{
-    memcpy(state, &current_ekf_state, sizeof(state));
-}
-
-void AttPosEKF::GetLastErrorState(struct ekf_status_report *last_error)
-{
-    memcpy(last_error, &last_ekf_error, sizeof(last_error));
-}
diff --git a/src/modules/fw_att_pos_estimator/fw_att_pos_estimator_params.c b/src/modules/fw_att_pos_estimator/fw_att_pos_estimator_params.c
deleted file mode 100644
index 6138ef39c..000000000
--- a/src/modules/fw_att_pos_estimator/fw_att_pos_estimator_params.c
+++ /dev/null
@@ -1,117 +0,0 @@
-/****************************************************************************
- *
- *   Copyright (c) 2013, 2014 PX4 Development Team. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in
- *    the documentation and/or other materials provided with the
- *    distribution.
- * 3. Neither the name PX4 nor the names of its contributors may be
- *    used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- ****************************************************************************/
-
-/**
- * @file fw_att_pos_estimator_params.c
- *
- * Parameters defined by the attitude and position estimator task
- *
- * @author Lorenz Meier <lm@inf.ethz.ch>
- */
-
-#include <nuttx/config.h>
-
-#include <systemlib/param/param.h>
-
-/*
- * Estimator parameters, accessible via MAVLink
- *
- */
-
-/**
- * Velocity estimate delay
- *
- * The delay in milliseconds of the velocity estimate from GPS.
- *
- * @min 0
- * @max 1000
- * @group Position Estimator
- */
-PARAM_DEFINE_INT32(PE_VEL_DELAY_MS, 230);
-
-/**
- * Position estimate delay
- *
- * The delay in milliseconds of the position estimate from GPS.
- *
- * @min 0
- * @max 1000
- * @group Position Estimator
- */
-PARAM_DEFINE_INT32(PE_POS_DELAY_MS, 210);
-
-/**
- * Height estimate delay
- *
- * The delay in milliseconds of the height estimate from the barometer.
- *
- * @min 0
- * @max 1000
- * @group Position Estimator
- */
-PARAM_DEFINE_INT32(PE_HGT_DELAY_MS, 350);
-
-/**
- * Mag estimate delay
- *
- * The delay in milliseconds of the magnetic field estimate from
- * the magnetometer.
- *
- * @min 0
- * @max 1000
- * @group Position Estimator
- */
-PARAM_DEFINE_INT32(PE_MAG_DELAY_MS, 30);
-
-/**
- * True airspeeed estimate delay
- *
- * The delay in milliseconds of the airspeed estimate.
- *
- * @min 0
- * @max 1000
- * @group Position Estimator
- */
-PARAM_DEFINE_INT32(PE_TAS_DELAY_MS, 210);
-
-/**
- * GPS vs. barometric altitude update weight
- *
- * RE-CHECK this.
- *
- * @min 0.0
- * @max 1.0
- * @group Position Estimator
- */
-PARAM_DEFINE_FLOAT(PE_GPS_ALT_WGT, 0.9f);
-
diff --git a/src/modules/mavlink/mavlink_main.cpp b/src/modules/mavlink/mavlink_main.cpp
index 1ba3d70c6..be4114e73 100644
--- a/src/modules/mavlink/mavlink_main.cpp
+++ b/src/modules/mavlink/mavlink_main.cpp
@@ -189,9 +189,18 @@ mavlink_send_uart_bytes(mavlink_channel_t channel, const uint8_t *ch, int length
 	/* If the wait until transmit flag is on, only transmit after we've received messages.
 	   Otherwise, transmit all the time. */
 	if (instance->should_transmit()) {
-	   ssize_t ret = write(uart, ch, desired);
+
+		/* check if there is space in the buffer, let it overflow else */
+		if (!ioctl(uart, FIONWRITE, (unsigned long)&buf_free)) {
+
+			if (desired > buf_free) {
+				desired = buf_free;
+			}
+		}
+
+		ssize_t ret = write(uart, ch, desired);
 		if (ret != desired) {
-			// XXX do something here, but change to using FIONWRITE and OS buf size for detection
+			warnx("TX FAIL");
 		}
 	}
 
diff --git a/src/modules/mavlink/mavlink_receiver.cpp b/src/modules/mavlink/mavlink_receiver.cpp
index 22cf9d7a6..33a4fef12 100644
--- a/src/modules/mavlink/mavlink_receiver.cpp
+++ b/src/modules/mavlink/mavlink_receiver.cpp
@@ -257,6 +257,7 @@ MavlinkReceiver::handle_message_optical_flow(mavlink_message_t *msg)
 	memset(&f, 0, sizeof(f));
 
 	f.timestamp = hrt_absolute_time();
+	f.flow_timestamp = flow.time_usec;
 	f.flow_raw_x = flow.flow_x;
 	f.flow_raw_y = flow.flow_y;
 	f.flow_comp_x_m = flow.flow_comp_m_x;
@@ -751,7 +752,6 @@ MavlinkReceiver::handle_message_hil_state_quaternion(mavlink_message_t *msg)
 		memset(&hil_global_pos, 0, sizeof(hil_global_pos));
 
 		hil_global_pos.timestamp = timestamp;
-		hil_global_pos.global_valid = true;
 		hil_global_pos.lat = hil_state.lat;
 		hil_global_pos.lon = hil_state.lon;
 		hil_global_pos.alt = hil_state.alt / 1000.0f;
@@ -759,6 +759,8 @@ MavlinkReceiver::handle_message_hil_state_quaternion(mavlink_message_t *msg)
 		hil_global_pos.vel_e = hil_state.vy / 100.0f;
 		hil_global_pos.vel_d = hil_state.vz / 100.0f;
 		hil_global_pos.yaw = hil_attitude.yaw;
+		hil_global_pos.eph = 2.0f;
+		hil_global_pos.epv = 4.0f;
 
 		if (_global_pos_pub < 0) {
 			_global_pos_pub = orb_advertise(ORB_ID(vehicle_global_position), &hil_global_pos);
@@ -770,19 +772,22 @@ MavlinkReceiver::handle_message_hil_state_quaternion(mavlink_message_t *msg)
 
 	/* local position */
 	{
+		double lat = hil_state.lat * 1e-7;
+		double lon = hil_state.lon * 1e-7;
+
 		if (!_hil_local_proj_inited) {
 			_hil_local_proj_inited = true;
 			_hil_local_alt0 = hil_state.alt / 1000.0f;
-			map_projection_init(hil_state.lat, hil_state.lon);
+			map_projection_init(&_hil_local_proj_ref, hil_state.lat, hil_state.lon);
 			hil_local_pos.ref_timestamp = timestamp;
-			hil_local_pos.ref_lat = hil_state.lat;
-			hil_local_pos.ref_lon = hil_state.lon;
+			hil_local_pos.ref_lat = lat;
+			hil_local_pos.ref_lon = lon;
 			hil_local_pos.ref_alt = _hil_local_alt0;
 		}
 
 		float x;
 		float y;
-		map_projection_project(hil_state.lat * 1e-7, hil_state.lon * 1e-7, &x, &y);
+		map_projection_project(&_hil_local_proj_ref, lat, lon, &x, &y);
 		hil_local_pos.timestamp = timestamp;
 		hil_local_pos.xy_valid = true;
 		hil_local_pos.z_valid = true;
diff --git a/src/modules/mavlink/mavlink_receiver.h b/src/modules/mavlink/mavlink_receiver.h
index 72ce4560f..9ab84b58a 100644
--- a/src/modules/mavlink/mavlink_receiver.h
+++ b/src/modules/mavlink/mavlink_receiver.h
@@ -142,4 +142,5 @@ private:
 	uint64_t _old_timestamp;
 	bool _hil_local_proj_inited;
 	float _hil_local_alt0;
+	struct map_projection_reference_s _hil_local_proj_ref;
 };
diff --git a/src/modules/mc_pos_control/mc_pos_control_main.cpp b/src/modules/mc_pos_control/mc_pos_control_main.cpp
index 7d3d39d18..65f4cbeaa 100644
--- a/src/modules/mc_pos_control/mc_pos_control_main.cpp
+++ b/src/modules/mc_pos_control/mc_pos_control_main.cpp
@@ -1,7 +1,6 @@
 /****************************************************************************
  *
- *   Copyright (c) 2013 PX4 Development Team. All rights reserved.
- *   Author: @author Anton Babushkin <anton.babushkin@me.com>
+ *   Copyright (c) 2013, 2014 PX4 Development Team. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -40,6 +39,8 @@
  * Output of velocity controller is thrust vector that splitted to thrust direction
  * (i.e. rotation matrix for multicopter orientation) and thrust module (i.e. multicopter thrust itself).
  * Controller doesn't use Euler angles for work, they generated only for more human-friendly control and logging.
+ *
+ * @author Anton Babushkin <anton.babushkin@me.com>
  */
 
 #include <nuttx/config.h>
@@ -62,9 +63,10 @@
 #include <uORB/topics/vehicle_control_mode.h>
 #include <uORB/topics/actuator_armed.h>
 #include <uORB/topics/parameter_update.h>
-#include <uORB/topics/vehicle_global_position.h>
+#include <uORB/topics/vehicle_local_position.h>
 #include <uORB/topics/position_setpoint_triplet.h>
 #include <uORB/topics/vehicle_global_velocity_setpoint.h>
+#include <uORB/topics/vehicle_local_position_setpoint.h>
 #include <systemlib/param/param.h>
 #include <systemlib/err.h>
 #include <systemlib/systemlib.h>
@@ -114,20 +116,21 @@ private:
 	int 	_params_sub;			/**< notification of parameter updates */
 	int 	_manual_sub;			/**< notification of manual control updates */
 	int		_arming_sub;			/**< arming status of outputs */
-	int		_global_pos_sub;			/**< vehicle local position */
+	int		_local_pos_sub;			/**< vehicle local position */
 	int		_pos_sp_triplet_sub;		/**< position setpoint triplet */
 
 	orb_advert_t	_att_sp_pub;			/**< attitude setpoint publication */
-	orb_advert_t	_pos_sp_triplet_pub;	/**< position setpoint triplet publication */
-	orb_advert_t	_global_vel_sp_pub;		/**< vehicle global velocity setpoint */
+	orb_advert_t	_local_pos_sp_pub;		/**< vehicle local position setpoint publication */
+	orb_advert_t	_global_vel_sp_pub;		/**< vehicle global velocity setpoint publication */
 
 	struct vehicle_attitude_s			_att;			/**< vehicle attitude */
 	struct vehicle_attitude_setpoint_s	_att_sp;		/**< vehicle attitude setpoint */
 	struct manual_control_setpoint_s	_manual;		/**< r/c channel data */
 	struct vehicle_control_mode_s		_control_mode;	/**< vehicle control mode */
 	struct actuator_armed_s				_arming;		/**< actuator arming status */
-	struct vehicle_global_position_s		_global_pos;	/**< vehicle global position */
+	struct vehicle_local_position_s		_local_pos;		/**< vehicle local position */
 	struct position_setpoint_triplet_s		_pos_sp_triplet;	/**< vehicle global position setpoint triplet */
+	struct vehicle_local_position_setpoint_s	_local_pos_sp;		/**< vehicle local position setpoint */
 	struct vehicle_global_velocity_setpoint_s	_global_vel_sp;	/**< vehicle global velocity setpoint */
 
 	struct {
@@ -166,14 +169,15 @@ private:
 		math::Vector<3> sp_offs_max;
 	}		_params;
 
-	double _lat_sp;
-	double _lon_sp;
-	float _alt_sp;
+	struct map_projection_reference_s _ref_pos;
+	float _ref_alt;
+	hrt_abstime _ref_timestamp;
 
-	bool _reset_lat_lon_sp;
+	bool _reset_pos_sp;
 	bool _reset_alt_sp;
-	bool _use_global_alt;			/**< switch between global (AMSL) and barometric altitudes */
 
+	math::Vector<3> _pos;
+	math::Vector<3> _pos_sp;
 	math::Vector<3> _vel;
 	math::Vector<3> _vel_sp;
 	math::Vector<3> _vel_prev;			/**< velocity on previous step */
@@ -196,9 +200,13 @@ private:
 	static float	scale_control(float ctl, float end, float dz);
 
 	/**
-	 * Reset lat/lon to current position
+	 * Update reference for local position projection
+	 */
+	void		update_ref();
+	/**
+	 * Reset position setpoint to current position
 	 */
-	void		reset_lat_lon_sp();
+	void		reset_pos_sp();
 
 	/**
 	 * Reset altitude setpoint to current altitude
@@ -246,31 +254,32 @@ MulticopterPositionControl::MulticopterPositionControl() :
 	_params_sub(-1),
 	_manual_sub(-1),
 	_arming_sub(-1),
-	_global_pos_sub(-1),
+	_local_pos_sub(-1),
 	_pos_sp_triplet_sub(-1),
 
 /* publications */
 	_att_sp_pub(-1),
-	_pos_sp_triplet_pub(-1),
+	_local_pos_sp_pub(-1),
 	_global_vel_sp_pub(-1),
 
-	_lat_sp(0.0),
-	_lon_sp(0.0),
-	_alt_sp(0.0f),
+	_ref_alt(0.0f),
+	_ref_timestamp(0),
 
-	_reset_lat_lon_sp(true),
-	_reset_alt_sp(true),
-	_use_global_alt(false)
+	_reset_pos_sp(true),
+	_reset_alt_sp(true)
 {
 	memset(&_att, 0, sizeof(_att));
 	memset(&_att_sp, 0, sizeof(_att_sp));
 	memset(&_manual, 0, sizeof(_manual));
 	memset(&_control_mode, 0, sizeof(_control_mode));
 	memset(&_arming, 0, sizeof(_arming));
-	memset(&_global_pos, 0, sizeof(_global_pos));
+	memset(&_local_pos, 0, sizeof(_local_pos));
 	memset(&_pos_sp_triplet, 0, sizeof(_pos_sp_triplet));
+	memset(&_local_pos_sp, 0, sizeof(_local_pos_sp));
 	memset(&_global_vel_sp, 0, sizeof(_global_vel_sp));
 
+	memset(&_ref_pos, 0, sizeof(_ref_pos));
+
 	_params.pos_p.zero();
 	_params.vel_p.zero();
 	_params.vel_i.zero();
@@ -279,6 +288,8 @@ MulticopterPositionControl::MulticopterPositionControl() :
 	_params.vel_ff.zero();
 	_params.sp_offs_max.zero();
 
+	_pos.zero();
+	_pos_sp.zero();
 	_vel.zero();
 	_vel_sp.zero();
 	_vel_prev.zero();
@@ -337,15 +348,18 @@ MulticopterPositionControl::parameters_update(bool force)
 
 	orb_check(_params_sub, &updated);
 
-	if (updated)
+	if (updated) {
 		orb_copy(ORB_ID(parameter_update), _params_sub, &param_upd);
+	}
 
 	if (updated || force) {
 		param_get(_params_handles.thr_min, &_params.thr_min);
 		param_get(_params_handles.thr_max, &_params.thr_max);
 		param_get(_params_handles.tilt_max, &_params.tilt_max);
+		_params.tilt_max = math::radians(_params.tilt_max);
 		param_get(_params_handles.land_speed, &_params.land_speed);
 		param_get(_params_handles.land_tilt_max, &_params.land_tilt_max);
+		_params.land_tilt_max = math::radians(_params.land_tilt_max);
 
 		float v;
 		param_get(_params_handles.xy_p, &v);
@@ -392,33 +406,39 @@ MulticopterPositionControl::poll_subscriptions()
 
 	orb_check(_att_sub, &updated);
 
-	if (updated)
+	if (updated) {
 		orb_copy(ORB_ID(vehicle_attitude), _att_sub, &_att);
+	}
 
 	orb_check(_att_sp_sub, &updated);
 
-	if (updated)
+	if (updated) {
 		orb_copy(ORB_ID(vehicle_attitude_setpoint), _att_sp_sub, &_att_sp);
+	}
 
 	orb_check(_control_mode_sub, &updated);
 
-	if (updated)
+	if (updated) {
 		orb_copy(ORB_ID(vehicle_control_mode), _control_mode_sub, &_control_mode);
+	}
 
 	orb_check(_manual_sub, &updated);
 
-	if (updated)
+	if (updated) {
 		orb_copy(ORB_ID(manual_control_setpoint), _manual_sub, &_manual);
+	}
 
 	orb_check(_arming_sub, &updated);
 
-	if (updated)
+	if (updated) {
 		orb_copy(ORB_ID(actuator_armed), _arming_sub, &_arming);
+	}
 
-	orb_check(_global_pos_sub, &updated);
+	orb_check(_local_pos_sub, &updated);
 
-	if (updated)
-		orb_copy(ORB_ID(vehicle_global_position), _global_pos_sub, &_global_pos);
+	if (updated) {
+		orb_copy(ORB_ID(vehicle_local_position), _local_pos_sub, &_local_pos);
+	}
 }
 
 float
@@ -442,40 +462,50 @@ MulticopterPositionControl::task_main_trampoline(int argc, char *argv[])
 }
 
 void
-MulticopterPositionControl::reset_lat_lon_sp()
+MulticopterPositionControl::update_ref()
 {
-	if (_reset_lat_lon_sp) {
-		_reset_lat_lon_sp = false;
-		_lat_sp = _global_pos.lat;
-		_lon_sp = _global_pos.lon;
-		mavlink_log_info(_mavlink_fd, "[mpc] reset lat/lon sp: %.7f, %.7f", _lat_sp, _lon_sp);
+	if (_local_pos.ref_timestamp != _ref_timestamp) {
+		double lat_sp, lon_sp;
+		float alt_sp;
+
+		if (_ref_timestamp != 0) {
+			/* calculate current position setpoint in global frame */
+			map_projection_reproject(&_ref_pos, _pos_sp(0), _pos_sp(1), &lat_sp, &lon_sp);
+			alt_sp = _ref_alt - _pos_sp(2);
+		}
+
+		/* update local projection reference */
+		map_projection_init(&_ref_pos, _local_pos.ref_lat, _local_pos.ref_lon);
+		_ref_alt = _local_pos.ref_alt;
+
+		if (_ref_timestamp != 0) {
+			/* reproject position setpoint to new reference */
+			map_projection_project(&_ref_pos, lat_sp, lon_sp, &_pos_sp.data[0], &_pos_sp.data[1]);
+			_pos_sp(2) = -(alt_sp - _ref_alt);
+		}
+
+		_ref_timestamp = _local_pos.ref_timestamp;
 	}
 }
 
 void
-MulticopterPositionControl::reset_alt_sp()
+MulticopterPositionControl::reset_pos_sp()
 {
-	if (_reset_alt_sp) {
-		_reset_alt_sp = false;
-		_alt_sp = _use_global_alt ? _global_pos.alt : _global_pos.baro_alt;
-		mavlink_log_info(_mavlink_fd, "[mpc] reset alt (%s) sp: %.2f", _use_global_alt ? "AMSL" : "baro", (double)_alt_sp);
+	if (_reset_pos_sp) {
+		_reset_pos_sp = false;
+		_pos_sp(0) = _pos(0);
+		_pos_sp(1) = _pos(1);
+		mavlink_log_info(_mavlink_fd, "[mpc] reset pos sp: %.2f, %.2f", (double)_pos_sp(0), (double)_pos_sp(1));
 	}
 }
 
 void
-MulticopterPositionControl::select_alt(bool global)
+MulticopterPositionControl::reset_alt_sp()
 {
-	if (global != _use_global_alt) {
-		_use_global_alt = global;
-
-		if (global) {
-			/* switch from barometric to global altitude */
-			_alt_sp += _global_pos.alt - _global_pos.baro_alt;
-
-		} else {
-			/* switch from global to barometric altitude */
-			_alt_sp += _global_pos.baro_alt - _global_pos.alt;
-		}
+	if (_reset_alt_sp) {
+		_reset_alt_sp = false;
+		_pos_sp(2) = _pos(2);
+		mavlink_log_info(_mavlink_fd, "[mpc] reset alt sp: %.2f", -(double)_pos_sp(2));
 	}
 }
 
@@ -496,7 +526,7 @@ MulticopterPositionControl::task_main()
 	_params_sub = orb_subscribe(ORB_ID(parameter_update));
 	_manual_sub = orb_subscribe(ORB_ID(manual_control_setpoint));
 	_arming_sub = orb_subscribe(ORB_ID(actuator_armed));
-	_global_pos_sub = orb_subscribe(ORB_ID(vehicle_global_position));
+	_local_pos_sub = orb_subscribe(ORB_ID(vehicle_local_position));
 	_pos_sp_triplet_sub = orb_subscribe(ORB_ID(position_setpoint_triplet));
 
 	parameters_update(true);
@@ -527,8 +557,7 @@ MulticopterPositionControl::task_main()
 	/* wakeup source */
 	struct pollfd fds[1];
 
-	/* Setup of loop */
-	fds[0].fd = _global_pos_sub;
+	fds[0].fd = _local_pos_sub;
 	fds[0].events = POLLIN;
 
 	while (!_task_should_exit) {
@@ -536,8 +565,9 @@ MulticopterPositionControl::task_main()
 		int pret = poll(&fds[0], (sizeof(fds) / sizeof(fds[0])), 500);
 
 		/* timed out - periodic check for _task_should_exit */
-		if (pret == 0)
+		if (pret == 0) {
 			continue;
+		}
 
 		/* this is undesirable but not much we can do */
 		if (pret < 0) {
@@ -554,7 +584,7 @@ MulticopterPositionControl::task_main()
 
 		if (_control_mode.flag_armed && !was_armed) {
 			/* reset setpoints and integrals on arming */
-			_reset_lat_lon_sp = true;
+			_reset_pos_sp = true;
 			_reset_alt_sp = true;
 			reset_int_z = true;
 			reset_int_xy = true;
@@ -562,28 +592,25 @@ MulticopterPositionControl::task_main()
 
 		was_armed = _control_mode.flag_armed;
 
+		update_ref();
+
 		if (_control_mode.flag_control_altitude_enabled ||
 		    _control_mode.flag_control_position_enabled ||
 		    _control_mode.flag_control_climb_rate_enabled ||
 		    _control_mode.flag_control_velocity_enabled) {
 
-			_vel(0) = _global_pos.vel_n;
-			_vel(1) = _global_pos.vel_e;
-			_vel(2) = _global_pos.vel_d;
+			_pos(0) = _local_pos.x;
+			_pos(1) = _local_pos.y;
+			_pos(2) = _local_pos.z;
 
-			sp_move_rate.zero();
+			_vel(0) = _local_pos.vx;
+			_vel(1) = _local_pos.vy;
+			_vel(2) = _local_pos.vz;
 
-			float alt = _global_pos.alt;
+			sp_move_rate.zero();
 
 			/* select control source */
 			if (_control_mode.flag_control_manual_enabled) {
-				/* select altitude source and update setpoint */
-				select_alt(_global_pos.global_valid);
-
-				if (!_use_global_alt) {
-					alt = _global_pos.baro_alt;
-				}
-
 				/* manual control */
 				if (_control_mode.flag_control_altitude_enabled) {
 					/* reset alt setpoint to current altitude if needed */
@@ -594,8 +621,8 @@ MulticopterPositionControl::task_main()
 				}
 
 				if (_control_mode.flag_control_position_enabled) {
-					/* reset lat/lon setpoint to current position if needed */
-					reset_lat_lon_sp();
+					/* reset position setpoint to current position if needed */
+					reset_pos_sp();
 
 					/* move position setpoint with roll/pitch stick */
 					sp_move_rate(0) = _manual.pitch;
@@ -615,74 +642,47 @@ MulticopterPositionControl::task_main()
 				sp_move_rate = R_yaw_sp * sp_move_rate.emult(_params.vel_max);
 
 				/* move position setpoint */
-				add_vector_to_global_position(_lat_sp, _lon_sp, sp_move_rate(0) * dt, sp_move_rate(1) * dt, &_lat_sp, &_lon_sp);
-				_alt_sp -= sp_move_rate(2) * dt;
+				_pos_sp += sp_move_rate * dt;
 
 				/* check if position setpoint is too far from actual position */
 				math::Vector<3> pos_sp_offs;
 				pos_sp_offs.zero();
 
 				if (_control_mode.flag_control_position_enabled) {
-					get_vector_to_next_waypoint_fast(_global_pos.lat, _global_pos.lon, _lat_sp, _lon_sp, &pos_sp_offs.data[0], &pos_sp_offs.data[1]);
-					pos_sp_offs(0) /= _params.sp_offs_max(0);
-					pos_sp_offs(1) /= _params.sp_offs_max(1);
+					pos_sp_offs(0) = (_pos_sp(0) - _pos(0)) / _params.sp_offs_max(0);
+					pos_sp_offs(1) = (_pos_sp(1) - _pos(1)) / _params.sp_offs_max(1);
 				}
 
 				if (_control_mode.flag_control_altitude_enabled) {
-					pos_sp_offs(2) = -(_alt_sp - alt) / _params.sp_offs_max(2);
+					pos_sp_offs(2) = (_pos_sp(2) - _pos(2)) / _params.sp_offs_max(2);
 				}
 
 				float pos_sp_offs_norm = pos_sp_offs.length();
 
 				if (pos_sp_offs_norm > 1.0f) {
 					pos_sp_offs /= pos_sp_offs_norm;
-					add_vector_to_global_position(_global_pos.lat, _global_pos.lon, pos_sp_offs(0) * _params.sp_offs_max(0), pos_sp_offs(1) * _params.sp_offs_max(1), &_lat_sp, &_lon_sp);
-					_alt_sp = alt - pos_sp_offs(2) * _params.sp_offs_max(2);
-				}
-
-				/* fill position setpoint triplet */
-				_pos_sp_triplet.previous.valid = true;
-				_pos_sp_triplet.current.valid = true;
-				_pos_sp_triplet.next.valid = true;
-
-				// _pos_sp_triplet.nav_state = NAV_STATE_NONE;
-				_pos_sp_triplet.current.type = SETPOINT_TYPE_NORMAL;
-				_pos_sp_triplet.current.lat = _lat_sp;
-				_pos_sp_triplet.current.lon = _lon_sp;
-				_pos_sp_triplet.current.alt = _alt_sp;
-				_pos_sp_triplet.current.yaw = _att_sp.yaw_body;
-				_pos_sp_triplet.current.loiter_radius = 0.0f;
-				_pos_sp_triplet.current.loiter_direction = 1.0f;
-				_pos_sp_triplet.current.pitch_min = 0.0f;
-
-				/* publish position setpoint triplet */
-				if (_pos_sp_triplet_pub > 0) {
-					orb_publish(ORB_ID(position_setpoint_triplet), _pos_sp_triplet_pub, &_pos_sp_triplet);
-
-				} else {
-					_pos_sp_triplet_pub = orb_advertise(ORB_ID(position_setpoint_triplet), &_pos_sp_triplet);
+					_pos_sp = _pos + pos_sp_offs.emult(_params.sp_offs_max);
 				}
 
 			} else {
-				/* always use AMSL altitude for AUTO */
-				select_alt(true);
-
 				/* AUTO */
 				bool updated;
 				orb_check(_pos_sp_triplet_sub, &updated);
 
-				if (updated)
+				if (updated) {
 					orb_copy(ORB_ID(position_setpoint_triplet), _pos_sp_triplet_sub, &_pos_sp_triplet);
+				}
 
 				if (_pos_sp_triplet.current.valid) {
 					/* in case of interrupted mission don't go to waypoint but stay at current position */
-					_reset_lat_lon_sp = true;
+					_reset_pos_sp = true;
 					_reset_alt_sp = true;
 
-					/* update position setpoint */
-					_lat_sp = _pos_sp_triplet.current.lat;
-					_lon_sp = _pos_sp_triplet.current.lon;
-					_alt_sp = _pos_sp_triplet.current.alt;
+					/* project setpoint to local frame */
+					map_projection_project(&_ref_pos,
+							       _pos_sp_triplet.current.lat, _pos_sp_triplet.current.lon,
+							       &_pos_sp.data[0], &_pos_sp.data[1]);
+					_pos_sp(2) = -(_pos_sp_triplet.current.alt - _ref_alt);
 
 					/* update yaw setpoint if needed */
 					if (isfinite(_pos_sp_triplet.current.yaw)) {
@@ -691,11 +691,25 @@ MulticopterPositionControl::task_main()
 
 				} else {
 					/* no waypoint, loiter, reset position setpoint if needed */
-					reset_lat_lon_sp();
+					reset_pos_sp();
 					reset_alt_sp();
 				}
 			}
 
+			/* fill local position setpoint */
+			_local_pos_sp.x = _pos_sp(0);
+			_local_pos_sp.y = _pos_sp(1);
+			_local_pos_sp.z = _pos_sp(2);
+			_local_pos_sp.yaw = _att_sp.yaw_body;
+
+			/* publish local position setpoint */
+			if (_local_pos_sp_pub > 0) {
+				orb_publish(ORB_ID(vehicle_local_position_setpoint), _local_pos_sp_pub, &_local_pos_sp);
+
+			} else {
+				_local_pos_sp_pub = orb_advertise(ORB_ID(vehicle_local_position_setpoint), &_local_pos_sp);
+			}
+
 			if (!_control_mode.flag_control_manual_enabled && _pos_sp_triplet.current.valid && _pos_sp_triplet.current.type == SETPOINT_TYPE_IDLE) {
 				/* idle state, don't run controller and set zero thrust */
 				R.identity();
@@ -719,9 +733,7 @@ MulticopterPositionControl::task_main()
 
 			} else {
 				/* run position & altitude controllers, calculate velocity setpoint */
-				math::Vector<3> pos_err;
-				get_vector_to_next_waypoint_fast(_global_pos.lat, _global_pos.lon, _lat_sp, _lon_sp, &pos_err.data[0], &pos_err.data[1]);
-				pos_err(2) = -(_alt_sp - alt);
+				math::Vector<3> pos_err = _pos_sp - _pos;
 
 				_vel_sp = pos_err.emult(_params.pos_p) + sp_move_rate.emult(_params.vel_ff);
 
@@ -731,7 +743,7 @@ MulticopterPositionControl::task_main()
 				}
 
 				if (!_control_mode.flag_control_position_enabled) {
-					_reset_lat_lon_sp = true;
+					_reset_pos_sp = true;
 					_vel_sp(0) = 0.0f;
 					_vel_sp(1) = 0.0f;
 				}
@@ -837,8 +849,9 @@ MulticopterPositionControl::task_main()
 						/* limit max tilt and min lift when landing */
 						tilt_max = _params.land_tilt_max;
 
-						if (thr_min < 0.0f)
+						if (thr_min < 0.0f) {
 							thr_min = 0.0f;
+						}
 					}
 
 					/* limit min lift */
@@ -929,8 +942,9 @@ MulticopterPositionControl::task_main()
 						thrust_int(2) += vel_err(2) * _params.vel_i(2) * dt;
 
 						/* protection against flipping on ground when landing */
-						if (thrust_int(2) > 0.0f)
+						if (thrust_int(2) > 0.0f) {
 							thrust_int(2) = 0.0f;
+						}
 					}
 
 					/* calculate attitude setpoint from thrust vector */
@@ -989,6 +1003,18 @@ MulticopterPositionControl::task_main()
 						_att_sp.roll_body = euler(0);
 						_att_sp.pitch_body = euler(1);
 						/* yaw already used to construct rot matrix, but actual rotation matrix can have different yaw near singularity */
+
+					} else if (!_control_mode.flag_control_manual_enabled) {
+						/* autonomous altitude control without position control (failsafe landing),
+						 * force level attitude, don't change yaw */
+						R.from_euler(0.0f, 0.0f, _att_sp.yaw_body);
+
+						/* copy rotation matrix to attitude setpoint topic */
+						memcpy(&_att_sp.R_body[0][0], R.data, sizeof(_att_sp.R_body));
+						_att_sp.R_valid = true;
+
+						_att_sp.roll_body = 0.0f;
+						_att_sp.pitch_body = 0.0f;
 					}
 
 					_att_sp.thrust = thrust_abs;
@@ -1011,7 +1037,7 @@ MulticopterPositionControl::task_main()
 		} else {
 			/* position controller disabled, reset setpoints */
 			_reset_alt_sp = true;
-			_reset_lat_lon_sp = true;
+			_reset_pos_sp = true;
 			reset_int_z = true;
 			reset_int_xy = true;
 		}
@@ -1050,18 +1076,21 @@ MulticopterPositionControl::start()
 
 int mc_pos_control_main(int argc, char *argv[])
 {
-	if (argc < 1)
+	if (argc < 1) {
 		errx(1, "usage: mc_pos_control {start|stop|status}");
+	}
 
 	if (!strcmp(argv[1], "start")) {
 
-		if (pos_control::g_control != nullptr)
+		if (pos_control::g_control != nullptr) {
 			errx(1, "already running");
+		}
 
 		pos_control::g_control = new MulticopterPositionControl;
 
-		if (pos_control::g_control == nullptr)
+		if (pos_control::g_control == nullptr) {
 			errx(1, "alloc failed");
+		}
 
 		if (OK != pos_control::g_control->start()) {
 			delete pos_control::g_control;
@@ -1073,8 +1102,9 @@ int mc_pos_control_main(int argc, char *argv[])
 	}
 
 	if (!strcmp(argv[1], "stop")) {
-		if (pos_control::g_control == nullptr)
+		if (pos_control::g_control == nullptr) {
 			errx(1, "not running");
+		}
 
 		delete pos_control::g_control;
 		pos_control::g_control = nullptr;
diff --git a/src/modules/mc_pos_control/mc_pos_control_params.c b/src/modules/mc_pos_control/mc_pos_control_params.c
index 0082a5e6a..fe0004ea8 100644
--- a/src/modules/mc_pos_control/mc_pos_control_params.c
+++ b/src/modules/mc_pos_control/mc_pos_control_params.c
@@ -100,6 +100,7 @@ PARAM_DEFINE_FLOAT(MPC_Z_VEL_D, 0.0f);
  *
  * Maximum vertical velocity in AUTO mode and endpoint for stabilized modes (SEATBELT, EASY).
  *
+ * @unit m/s
  * @min 0.0
  * @group Multicopter Position Control
  */
@@ -155,6 +156,7 @@ PARAM_DEFINE_FLOAT(MPC_XY_VEL_D, 0.01f);
  *
  * Maximum horizontal velocity in AUTO mode and endpoint for position stabilized mode (EASY).
  *
+ * @unit m/s
  * @min 0.0
  * @group Multicopter Position Control
  */
@@ -176,15 +178,17 @@ PARAM_DEFINE_FLOAT(MPC_XY_FF, 0.5f);
  *
  * Limits maximum tilt in AUTO and EASY modes.
  *
+ * @unit deg
  * @min 0.0
- * @max 1.57
+ * @max 90.0
  * @group Multicopter Position Control
  */
-PARAM_DEFINE_FLOAT(MPC_TILT_MAX, 1.0f);
+PARAM_DEFINE_FLOAT(MPC_TILT_MAX, 45.0f);
 
 /**
  * Landing descend rate
  *
+ * @unit m/s
  * @min 0.0
  * @group Multicopter Position Control
  */
@@ -195,8 +199,9 @@ PARAM_DEFINE_FLOAT(MPC_LAND_SPEED, 1.0f);
  *
  * Limits maximum tilt on landing.
  *
+ * @unit deg
  * @min 0.0
- * @max 1.57
+ * @max 90.0
  * @group Multicopter Position Control
  */
-PARAM_DEFINE_FLOAT(MPC_LAND_TILT, 0.3f);
+PARAM_DEFINE_FLOAT(MPC_LAND_TILT, 15.0f);
diff --git a/src/modules/position_estimator_inav/position_estimator_inav_main.c b/src/modules/position_estimator_inav/position_estimator_inav_main.c
index 763b87563..368424853 100644
--- a/src/modules/position_estimator_inav/position_estimator_inav_main.c
+++ b/src/modules/position_estimator_inav/position_estimator_inav_main.c
@@ -1,7 +1,6 @@
 /****************************************************************************
  *
- *   Copyright (C) 2013 Anton Babushkin. All rights reserved.
- *   Author: 	Anton Babushkin	<rk3dov@gmail.com>
+ *   Copyright (C) 2013, 2014 PX4 Development Team. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -35,6 +34,8 @@
 /**
  * @file position_estimator_inav_main.c
  * Model-identification based position estimator for multirotors
+ *
+ * @author Anton Babushkin <anton.babushkin@me.com>
  */
 
 #include <unistd.h>
@@ -57,6 +58,7 @@
 #include <uORB/topics/vehicle_local_position.h>
 #include <uORB/topics/vehicle_global_position.h>
 #include <uORB/topics/vehicle_gps_position.h>
+#include <uORB/topics/home_position.h>
 #include <uORB/topics/optical_flow.h>
 #include <mavlink/mavlink_log.h>
 #include <poll.h>
@@ -95,8 +97,9 @@ static void usage(const char *reason);
  */
 static void usage(const char *reason)
 {
-	if (reason)
+	if (reason) {
 		fprintf(stderr, "%s\n", reason);
+	}
 
 	fprintf(stderr, "usage: position_estimator_inav {start|stop|status} [-v]\n\n");
 	exit(1);
@@ -112,8 +115,9 @@ static void usage(const char *reason)
  */
 int position_estimator_inav_main(int argc, char *argv[])
 {
-	if (argc < 1)
+	if (argc < 1) {
 		usage("missing command");
+	}
 
 	if (!strcmp(argv[1], "start")) {
 		if (thread_running) {
@@ -125,8 +129,9 @@ int position_estimator_inav_main(int argc, char *argv[])
 		verbose_mode = false;
 
 		if (argc > 1)
-			if (!strcmp(argv[2], "-v"))
+			if (!strcmp(argv[2], "-v")) {
 				verbose_mode = true;
+			}
 
 		thread_should_exit = false;
 		position_estimator_inav_task = task_spawn_cmd("position_estimator_inav",
@@ -163,16 +168,19 @@ int position_estimator_inav_main(int argc, char *argv[])
 	exit(1);
 }
 
-void write_debug_log(const char *msg, float dt, float x_est[3], float y_est[3], float z_est[3], float corr_acc[3], float corr_gps[3][2], float w_xy_gps_p, float w_xy_gps_v) {
+void write_debug_log(const char *msg, float dt, float x_est[3], float y_est[3], float z_est[3], float x_est_prev[3], float y_est_prev[3], float z_est_prev[3], float corr_acc[3], float corr_gps[3][2], float w_xy_gps_p, float w_xy_gps_v)
+{
 	FILE *f = fopen("/fs/microsd/inav.log", "a");
+
 	if (f) {
 		char *s = malloc(256);
-		unsigned n = snprintf(s, 256, "%llu %s\n\tdt=%.5f x_est=[%.5f %.5f %.5f] y_est=[%.5f %.5f %.5f] z_est=[%.5f %.5f %.5f]\n", hrt_absolute_time(), msg, dt, x_est[0], x_est[1], x_est[2], y_est[0], y_est[1], y_est[2], z_est[0], z_est[1], z_est[2]);
+		unsigned n = snprintf(s, 256, "%llu %s\n\tdt=%.5f x_est=[%.5f %.5f %.5f] y_est=[%.5f %.5f %.5f] z_est=[%.5f %.5f %.5f] x_est_prev=[%.5f %.5f %.5f] y_est_prev=[%.5f %.5f %.5f] z_est_prev=[%.5f %.5f %.5f]\n", hrt_absolute_time(), msg, dt, x_est[0], x_est[1], x_est[2], y_est[0], y_est[1], y_est[2], z_est[0], z_est[1], z_est[2], x_est_prev[0], x_est_prev[1], x_est_prev[2], y_est_prev[0], y_est_prev[1], y_est_prev[2], z_est_prev[0], z_est_prev[1], z_est_prev[2]);
 		fwrite(s, 1, n, f);
 		n = snprintf(s, 256, "\tacc_corr=[%.5f %.5f %.5f] gps_pos_corr=[%.5f %.5f %.5f] gps_vel_corr=[%.5f %.5f %.5f] w_xy_gps_p=%.5f w_xy_gps_v=%.5f\n", corr_acc[0], corr_acc[1], corr_acc[2], corr_gps[0][0], corr_gps[1][0], corr_gps[2][0], corr_gps[0][1], corr_gps[1][1], corr_gps[2][1], w_xy_gps_p, w_xy_gps_v);
 		fwrite(s, 1, n, f);
 		free(s);
 	}
+
 	fsync(fileno(f));
 	fclose(f);
 }
@@ -191,6 +199,11 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 	float y_est[3] = { 0.0f, 0.0f, 0.0f };
 	float z_est[3] = { 0.0f, 0.0f, 0.0f };
 
+	float x_est_prev[3], y_est_prev[3], z_est_prev[3];
+	memset(x_est_prev, 0, sizeof(x_est_prev));
+	memset(y_est_prev, 0, sizeof(y_est_prev));
+	memset(z_est_prev, 0, sizeof(z_est_prev));
+
 	int baro_init_cnt = 0;
 	int baro_init_num = 200;
 	float baro_offset = 0.0f;		// baro offset for reference altitude, initialized on start, then adjusted
@@ -206,6 +219,9 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 	bool ref_inited = false;
 	hrt_abstime ref_init_start = 0;
 	const hrt_abstime ref_init_delay = 1000000;	// wait for 1s after 3D fix
+	struct map_projection_reference_s ref;
+	memset(&ref, 0, sizeof(ref));
+	hrt_abstime home_timestamp = 0;
 
 	uint16_t accel_updates = 0;
 	uint16_t baro_updates = 0;
@@ -238,7 +254,11 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 	float corr_flow[] = { 0.0f, 0.0f };	// N E
 	float w_flow = 0.0f;
 
+	static float min_eph_epv = 2.0f;	// min EPH/EPV, used for weight calculation
+	static float max_eph_epv = 10.0f;	// max EPH/EPV acceptable for estimation
+
 	float sonar_prev = 0.0f;
+	hrt_abstime flow_prev = 0;			// time of last flow measurement
 	hrt_abstime sonar_time = 0;			// time of last sonar measurement (not filtered)
 	hrt_abstime sonar_valid_time = 0;	// time of last sonar measurement used for correction (filtered)
 	hrt_abstime xy_src_time = 0;		// time of last available position data
@@ -257,6 +277,8 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 	memset(&sensor, 0, sizeof(sensor));
 	struct vehicle_gps_position_s gps;
 	memset(&gps, 0, sizeof(gps));
+	struct home_position_s home;
+	memset(&home, 0, sizeof(home));
 	struct vehicle_attitude_s att;
 	memset(&att, 0, sizeof(att));
 	struct vehicle_local_position_s local_pos;
@@ -274,10 +296,11 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 	int vehicle_attitude_sub = orb_subscribe(ORB_ID(vehicle_attitude));
 	int optical_flow_sub = orb_subscribe(ORB_ID(optical_flow));
 	int vehicle_gps_position_sub = orb_subscribe(ORB_ID(vehicle_gps_position));
+	int home_position_sub = orb_subscribe(ORB_ID(home_position));
 
 	/* advertise */
 	orb_advert_t vehicle_local_position_pub = orb_advertise(ORB_ID(vehicle_local_position), &local_pos);
-	orb_advert_t vehicle_global_position_pub = orb_advertise(ORB_ID(vehicle_global_position), &global_pos);
+	orb_advert_t vehicle_global_position_pub = -1;
 
 	struct position_estimator_inav_params params;
 	struct position_estimator_inav_param_handles pos_inav_param_handles;
@@ -325,7 +348,6 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 						mavlink_log_info(mavlink_fd, "[inav] baro offs: %.2f", baro_offset);
 						local_pos.z_valid = true;
 						local_pos.v_z_valid = true;
-						global_pos.baro_valid = true;
 					}
 				}
 			}
@@ -425,6 +447,10 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 			if (updated) {
 				orb_copy(ORB_ID(optical_flow), optical_flow_sub, &flow);
 
+				/* calculate time from previous update */
+				float flow_dt = flow_prev > 0 ? (flow.flow_timestamp - flow_prev) * 1e-6f : 0.1f;
+				flow_prev = flow.flow_timestamp;
+
 				if (flow.ground_distance_m > 0.31f && flow.ground_distance_m < 4.0f && att.R[2][2] > 0.7 && flow.ground_distance_m != sonar_prev) {
 					sonar_time = t;
 					sonar_prev = flow.ground_distance_m;
@@ -475,10 +501,10 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 					flow_accurate = fabsf(body_v_est[1] / flow_dist - att.rollspeed) < max_flow &&
 							fabsf(body_v_est[0] / flow_dist + att.pitchspeed) < max_flow;
 
-					/* convert raw flow to angular flow */
+					/* convert raw flow to angular flow (rad/s) */
 					float flow_ang[2];
-					flow_ang[0] = flow.flow_raw_x * params.flow_k;
-					flow_ang[1] = flow.flow_raw_y * params.flow_k;
+					flow_ang[0] = flow.flow_raw_x * params.flow_k / 1000.0f / flow_dt;
+					flow_ang[1] = flow.flow_raw_y * params.flow_k / 1000.0f / flow_dt;
 					/* flow measurements vector */
 					float flow_m[3];
 					flow_m[0] = -flow_ang[0] * flow_dist;
@@ -503,8 +529,9 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 
 					/* if flow is not accurate, reduce weight for it */
 					// TODO make this more fuzzy
-					if (!flow_accurate)
+					if (!flow_accurate) {
 						w_flow *= 0.05f;
+					}
 
 					flow_valid = true;
 
@@ -516,32 +543,73 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 				flow_updates++;
 			}
 
+			/* home position */
+			orb_check(home_position_sub, &updated);
+
+			if (updated) {
+				orb_copy(ORB_ID(home_position), home_position_sub, &home);
+
+				if (home.timestamp != home_timestamp) {
+					home_timestamp = home.timestamp;
+
+					double est_lat, est_lon;
+					float est_alt;
+
+					if (ref_inited) {
+						/* calculate current estimated position in global frame */
+						est_alt = local_pos.ref_alt - local_pos.z;
+						map_projection_reproject(&ref, local_pos.x, local_pos.y, &est_lat, &est_lon);
+					}
+
+					/* update reference */
+					map_projection_init(&ref, home.lat, home.lon);
+
+					/* update baro offset */
+					baro_offset += home.alt - local_pos.ref_alt;
+
+					local_pos.ref_lat = home.lat;
+					local_pos.ref_lon = home.lon;
+					local_pos.ref_alt = home.alt;
+					local_pos.ref_timestamp = home.timestamp;
+
+					if (ref_inited) {
+						/* reproject position estimate with new reference */
+						map_projection_project(&ref, est_lat, est_lon, &x_est[0], &y_est[0]);
+						z_est[0] = -(est_alt - local_pos.ref_alt);
+					}
+
+					ref_inited = true;
+				}
+			}
+
 			/* vehicle GPS position */
 			orb_check(vehicle_gps_position_sub, &updated);
 
 			if (updated) {
 				orb_copy(ORB_ID(vehicle_gps_position), vehicle_gps_position_sub, &gps);
 
-				if (gps.fix_type >= 3) {
-					/* hysteresis for GPS quality */
-					if (gps_valid) {
-						if (gps.eph_m > 10.0f || gps.epv_m > 20.0f) {
-							gps_valid = false;
-							mavlink_log_info(mavlink_fd, "[inav] GPS signal lost");
-						}
+				bool reset_est = false;
 
-					} else {
-						if (gps.eph_m < 5.0f && gps.epv_m < 10.0f) {
-							gps_valid = true;
-							mavlink_log_info(mavlink_fd, "[inav] GPS signal found");
-						}
+				/* hysteresis for GPS quality */
+				if (gps_valid) {
+					if (gps.eph_m > max_eph_epv * 1.5f || gps.epv_m > max_eph_epv * 1.5f || gps.fix_type < 3) {
+						gps_valid = false;
+						mavlink_log_info(mavlink_fd, "[inav] GPS signal lost");
 					}
 
 				} else {
-					gps_valid = false;
+					if (gps.eph_m < max_eph_epv && gps.epv_m < max_eph_epv && gps.fix_type >= 3) {
+						gps_valid = true;
+						reset_est = true;
+						mavlink_log_info(mavlink_fd, "[inav] GPS signal found");
+					}
 				}
 
 				if (gps_valid) {
+					double lat = gps.lat * 1e-7;
+					double lon = gps.lon * 1e-7;
+					float alt = gps.alt * 1e-3;
+
 					/* initialize reference position if needed */
 					if (!ref_inited) {
 						if (ref_init_start == 0) {
@@ -549,18 +617,25 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 
 						} else if (t > ref_init_start + ref_init_delay) {
 							ref_inited = true;
-							/* reference GPS position */
-							double lat = gps.lat * 1e-7;
-							double lon = gps.lon * 1e-7;
-							float alt = gps.alt * 1e-3;
-
-							local_pos.ref_lat = gps.lat;
-							local_pos.ref_lon = gps.lon;
-							local_pos.ref_alt = alt + z_est[0];
+							/* update baro offset */
+							baro_offset -= z_est[0];
+
+							/* set position estimate to (0, 0, 0), use GPS velocity for XY */
+							x_est[0] = 0.0f;
+							x_est[1] = gps.vel_n_m_s;
+							x_est[2] = accel_NED[0];
+							y_est[0] = 0.0f;
+							y_est[1] = gps.vel_e_m_s;
+							z_est[0] = 0.0f;
+							y_est[2] = accel_NED[1];
+
+							local_pos.ref_lat = lat;
+							local_pos.ref_lon = lon;
+							local_pos.ref_alt = alt;
 							local_pos.ref_timestamp = t;
 
 							/* initialize projection */
-							map_projection_init(lat, lon);
+							map_projection_init(&ref, lat, lon);
 							warnx("init ref: lat=%.7f, lon=%.7f, alt=%.2f", lat, lon, alt);
 							mavlink_log_info(mavlink_fd, "[inav] init ref: lat=%.7f, lon=%.7f, alt=%.2f", lat, lon, alt);
 						}
@@ -569,11 +644,22 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 					if (ref_inited) {
 						/* project GPS lat lon to plane */
 						float gps_proj[2];
-						map_projection_project(gps.lat * 1e-7, gps.lon * 1e-7, &(gps_proj[0]), &(gps_proj[1]));
+						map_projection_project(&ref, lat, lon, &(gps_proj[0]), &(gps_proj[1]));
+
+						/* reset position estimate when GPS becomes good */
+						if (reset_est) {
+							x_est[0] = gps_proj[0];
+							x_est[1] = gps.vel_n_m_s;
+							x_est[2] = accel_NED[0];
+							y_est[0] = gps_proj[1];
+							y_est[1] = gps.vel_e_m_s;
+							y_est[2] = accel_NED[1];
+						}
+
 						/* calculate correction for position */
 						corr_gps[0][0] = gps_proj[0] - x_est[0];
 						corr_gps[1][0] = gps_proj[1] - y_est[0];
-						corr_gps[2][0] = local_pos.ref_alt - gps.alt * 1e-3 - z_est[0];
+						corr_gps[2][0] = local_pos.ref_alt - alt - z_est[0];
 
 						/* calculate correction for velocity */
 						if (gps.vel_ned_valid) {
@@ -587,8 +673,8 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 							corr_gps[2][1] = 0.0f;
 						}
 
-						w_gps_xy = 2.0f / fmaxf(2.0f, gps.eph_m);
-						w_gps_z = 4.0f / fmaxf(4.0f, gps.epv_m);
+						w_gps_xy = min_eph_epv / fmaxf(min_eph_epv, gps.eph_m);
+						w_gps_z = min_eph_epv / fmaxf(min_eph_epv, gps.epv_m);
 					}
 
 				} else {
@@ -704,23 +790,34 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 		/* inertial filter prediction for altitude */
 		inertial_filter_predict(dt, z_est);
 
+		if (!(isfinite(z_est[0]) && isfinite(z_est[1]) && isfinite(z_est[2]))) {
+			write_debug_log("BAD ESTIMATE AFTER Z PREDICTION", dt, x_est, y_est, z_est, x_est_prev, y_est_prev, z_est_prev, corr_acc, corr_gps, w_xy_gps_p, w_xy_gps_v);
+			memcpy(z_est, z_est_prev, sizeof(z_est));
+		}
+
 		/* inertial filter correction for altitude */
 		inertial_filter_correct(corr_baro, dt, z_est, 0, params.w_z_baro);
 		inertial_filter_correct(corr_gps[2][0], dt, z_est, 0, w_z_gps_p);
 		inertial_filter_correct(corr_acc[2], dt, z_est, 2, params.w_z_acc);
 
-		float x_est_prev[3], y_est_prev[3];
+		if (!(isfinite(z_est[0]) && isfinite(z_est[1]) && isfinite(z_est[2]))) {
+			write_debug_log("BAD ESTIMATE AFTER Z CORRECTION", dt, x_est, y_est, z_est, x_est_prev, y_est_prev, z_est_prev, corr_acc, corr_gps, w_xy_gps_p, w_xy_gps_v);
+			memcpy(z_est, z_est_prev, sizeof(z_est));
+			memset(corr_acc, 0, sizeof(corr_acc));
+			memset(corr_gps, 0, sizeof(corr_gps));
+			corr_baro = 0;
 
-		memcpy(x_est_prev, x_est, sizeof(x_est));
-		memcpy(y_est_prev, y_est, sizeof(y_est));
+		} else {
+			memcpy(z_est_prev, z_est, sizeof(z_est));
+		}
 
 		if (can_estimate_xy) {
 			/* inertial filter prediction for position */
 			inertial_filter_predict(dt, x_est);
 			inertial_filter_predict(dt, y_est);
 
-			if (!isfinite(x_est[0]) || !isfinite(y_est[0])) {
-				write_debug_log("BAD ESTIMATE AFTER PREDICTION", dt, x_est, y_est, z_est, corr_acc, corr_gps, w_xy_gps_p, w_xy_gps_v);
+			if (!(isfinite(x_est[0]) && isfinite(x_est[1]) && isfinite(x_est[2]) && isfinite(y_est[0]) && isfinite(y_est[1]) && isfinite(y_est[2]))) {
+				write_debug_log("BAD ESTIMATE AFTER PREDICTION", dt, x_est, y_est, z_est, x_est_prev, y_est_prev, z_est_prev, corr_acc, corr_gps, w_xy_gps_p, w_xy_gps_v);
 				memcpy(x_est, x_est_prev, sizeof(x_est));
 				memcpy(y_est, y_est_prev, sizeof(y_est));
 			}
@@ -744,13 +841,17 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 				}
 			}
 
-			if (!isfinite(x_est[0]) || !isfinite(y_est[0])) {
-				write_debug_log("BAD ESTIMATE AFTER CORRECTION", dt, x_est, y_est, z_est, corr_acc, corr_gps, w_xy_gps_p, w_xy_gps_v);
+			if (!(isfinite(x_est[0]) && isfinite(x_est[1]) && isfinite(x_est[2]) && isfinite(y_est[0]) && isfinite(y_est[1]) && isfinite(y_est[2]))) {
+				write_debug_log("BAD ESTIMATE AFTER CORRECTION", dt, x_est, y_est, z_est, x_est_prev, y_est_prev, z_est_prev, corr_acc, corr_gps, w_xy_gps_p, w_xy_gps_v);
 				memcpy(x_est, x_est_prev, sizeof(x_est));
 				memcpy(y_est, y_est_prev, sizeof(y_est));
 				memset(corr_acc, 0, sizeof(corr_acc));
 				memset(corr_gps, 0, sizeof(corr_gps));
 				memset(corr_flow, 0, sizeof(corr_flow));
+
+			} else {
+				memcpy(x_est_prev, x_est, sizeof(x_est));
+				memcpy(y_est_prev, y_est, sizeof(y_est));
 			}
 		}
 
@@ -808,7 +909,7 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 		if (t > pub_last + pub_interval) {
 			pub_last = t;
 			/* publish local position */
-			local_pos.xy_valid = can_estimate_xy && use_gps_xy;
+			local_pos.xy_valid = can_estimate_xy;
 			local_pos.v_xy_valid = can_estimate_xy;
 			local_pos.xy_global = local_pos.xy_valid && use_gps_xy;
 			local_pos.z_global = local_pos.z_valid && use_gps_z;
@@ -831,40 +932,35 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 
 			orb_publish(ORB_ID(vehicle_local_position), vehicle_local_position_pub, &local_pos);
 
-			/* publish global position */
-			global_pos.global_valid = local_pos.xy_global;
+			if (local_pos.xy_global && local_pos.z_global) {
+				/* publish global position */
+				global_pos.timestamp = t;
+				global_pos.time_gps_usec = gps.time_gps_usec;
 
-			if (local_pos.xy_global) {
 				double est_lat, est_lon;
-				map_projection_reproject(local_pos.x, local_pos.y, &est_lat, &est_lon);
+				map_projection_reproject(&ref, local_pos.x, local_pos.y, &est_lat, &est_lon);
+
 				global_pos.lat = est_lat;
 				global_pos.lon = est_lon;
-				global_pos.time_gps_usec = gps.time_gps_usec;
-			}
+				global_pos.alt = local_pos.ref_alt - local_pos.z;
 
-			/* set valid values even if position is not valid */
-			if (local_pos.v_xy_valid) {
 				global_pos.vel_n = local_pos.vx;
 				global_pos.vel_e = local_pos.vy;
-			}
-
-			if (local_pos.z_global) {
-				global_pos.alt = local_pos.ref_alt - local_pos.z;
-			}
-
-			if (local_pos.z_valid) {
-				global_pos.baro_alt = baro_offset - local_pos.z;
-			}
-
-			if (local_pos.v_z_valid) {
 				global_pos.vel_d = local_pos.vz;
-			}
 
-			global_pos.yaw = local_pos.yaw;
+				global_pos.yaw = local_pos.yaw;
+
+				// TODO implement dead-reckoning
+				global_pos.eph = gps.eph_m;
+				global_pos.epv = gps.epv_m;
 
-			global_pos.timestamp = t;
+				if (vehicle_global_position_pub < 0) {
+					vehicle_global_position_pub = orb_advertise(ORB_ID(vehicle_global_position), &global_pos);
 
-			orb_publish(ORB_ID(vehicle_global_position), vehicle_global_position_pub, &global_pos);
+				} else {
+					orb_publish(ORB_ID(vehicle_global_position), vehicle_global_position_pub, &global_pos);
+				}
+			}
 		}
 	}
 
diff --git a/src/modules/position_estimator_inav/position_estimator_inav_params.c b/src/modules/position_estimator_inav/position_estimator_inav_params.c
index dcad5c03b..2e4f26661 100644
--- a/src/modules/position_estimator_inav/position_estimator_inav_params.c
+++ b/src/modules/position_estimator_inav/position_estimator_inav_params.c
@@ -50,7 +50,7 @@ PARAM_DEFINE_FLOAT(INAV_W_XY_ACC, 20.0f);
 PARAM_DEFINE_FLOAT(INAV_W_XY_FLOW, 5.0f);
 PARAM_DEFINE_FLOAT(INAV_W_GPS_FLOW, 0.1f);
 PARAM_DEFINE_FLOAT(INAV_W_ACC_BIAS, 0.05f);
-PARAM_DEFINE_FLOAT(INAV_FLOW_K, 0.0165f);
+PARAM_DEFINE_FLOAT(INAV_FLOW_K, 0.15f);
 PARAM_DEFINE_FLOAT(INAV_FLOW_Q_MIN, 0.5f);
 PARAM_DEFINE_FLOAT(INAV_SONAR_FILT, 0.05f);
 PARAM_DEFINE_FLOAT(INAV_SONAR_ERR, 0.5f);
diff --git a/src/modules/sdlog2/sdlog2.c b/src/modules/sdlog2/sdlog2.c
index 543f15093..b74d4183b 100644
--- a/src/modules/sdlog2/sdlog2.c
+++ b/src/modules/sdlog2/sdlog2.c
@@ -960,6 +960,7 @@ int sdlog2_thread_main(int argc, char *argv[])
 			log_msg.msg_type = LOG_STAT_MSG;
 			log_msg.body.log_STAT.main_state = (uint8_t) buf_status.main_state;
 			log_msg.body.log_STAT.arming_state = (uint8_t) buf_status.arming_state;
+			log_msg.body.log_STAT.failsafe_state = (uint8_t) buf_status.failsafe_state;
 			log_msg.body.log_STAT.battery_remaining = buf_status.battery_remaining;
 			log_msg.body.log_STAT.battery_warning = (uint8_t) buf_status.battery_warning;
 			log_msg.body.log_STAT.landed = (uint8_t) buf_status.condition_landed;
@@ -1101,8 +1102,8 @@ int sdlog2_thread_main(int argc, char *argv[])
 			log_msg.body.log_LPOS.vx = buf.local_pos.vx;
 			log_msg.body.log_LPOS.vy = buf.local_pos.vy;
 			log_msg.body.log_LPOS.vz = buf.local_pos.vz;
-			log_msg.body.log_LPOS.ref_lat = buf.local_pos.ref_lat;
-			log_msg.body.log_LPOS.ref_lon = buf.local_pos.ref_lon;
+			log_msg.body.log_LPOS.ref_lat = buf.local_pos.ref_lat * 1e7;
+			log_msg.body.log_LPOS.ref_lon = buf.local_pos.ref_lon * 1e7;
 			log_msg.body.log_LPOS.ref_alt = buf.local_pos.ref_alt;
 			log_msg.body.log_LPOS.xy_flags = (buf.local_pos.xy_valid ? 1 : 0) | (buf.local_pos.v_xy_valid ? 2 : 0) | (buf.local_pos.xy_global ? 8 : 0);
 			log_msg.body.log_LPOS.z_flags = (buf.local_pos.z_valid ? 1 : 0) | (buf.local_pos.v_z_valid ? 2 : 0) | (buf.local_pos.z_global ? 8 : 0);
@@ -1130,8 +1131,8 @@ int sdlog2_thread_main(int argc, char *argv[])
 			log_msg.body.log_GPOS.vel_n = buf.global_pos.vel_n;
 			log_msg.body.log_GPOS.vel_e = buf.global_pos.vel_e;
 			log_msg.body.log_GPOS.vel_d = buf.global_pos.vel_d;
-			log_msg.body.log_GPOS.baro_alt = buf.global_pos.baro_alt;
-			log_msg.body.log_GPOS.flags = (buf.global_pos.baro_valid ? 1 : 0) | (buf.global_pos.global_valid ? 2 : 0);
+			log_msg.body.log_GPOS.eph = buf.global_pos.eph;
+			log_msg.body.log_GPOS.epv = buf.global_pos.epv;
 			LOGBUFFER_WRITE_AND_COUNT(GPOS);
 		}
 
diff --git a/src/modules/sdlog2/sdlog2_messages.h b/src/modules/sdlog2/sdlog2_messages.h
index 63386a5d7..595a787d6 100644
--- a/src/modules/sdlog2/sdlog2_messages.h
+++ b/src/modules/sdlog2/sdlog2_messages.h
@@ -154,6 +154,7 @@ struct log_ATTC_s {
 struct log_STAT_s {
 	uint8_t main_state;
 	uint8_t arming_state;
+	uint8_t failsafe_state;
 	float battery_remaining;
 	uint8_t battery_warning;
 	uint8_t landed;
@@ -210,8 +211,8 @@ struct log_GPOS_s {
 	float vel_n;
 	float vel_e;
 	float vel_d;
-	float baro_alt;
-	uint8_t flags;
+	float eph;
+	float epv;
 };
 
 /* --- GPSP - GLOBAL POSITION SETPOINT --- */
@@ -351,13 +352,13 @@ static const struct log_format_s log_formats[] = {
 	LOG_FORMAT(LPSP, "ffff",		"X,Y,Z,Yaw"),
 	LOG_FORMAT(GPS, "QBffLLfffff",		"GPSTime,FixType,EPH,EPV,Lat,Lon,Alt,VelN,VelE,VelD,Cog"),
 	LOG_FORMAT(ATTC, "ffff",		"Roll,Pitch,Yaw,Thrust"),
-	LOG_FORMAT(STAT, "BBfBB",		"MainState,ArmState,BatRem,BatWarn,Landed"),
-	LOG_FORMAT(RC, "ffffffffB",		"Ch0,Ch1,Ch2,Ch3,Ch4,Ch5,Ch6,Ch7,Count"),
+	LOG_FORMAT(STAT, "BBBfBB",		"MainState,ArmState,FailsafeState,BatRem,BatWarn,Landed"),
+	LOG_FORMAT(RC, "ffffffffBB",		"Ch0,Ch1,Ch2,Ch3,Ch4,Ch5,Ch6,Ch7,Count,SignalLost"),
 	LOG_FORMAT(OUT0, "ffffffff",		"Out0,Out1,Out2,Out3,Out4,Out5,Out6,Out7"),
 	LOG_FORMAT(AIRS, "fff",			"IndSpeed,TrueSpeed,AirTemp"),
 	LOG_FORMAT(ARSP, "fff",			"RollRateSP,PitchRateSP,YawRateSP"),
 	LOG_FORMAT(FLOW, "hhfffBB",		"RawX,RawY,CompX,CompY,Dist,Q,SensID"),
-	LOG_FORMAT(GPOS, "LLfffffB",		"Lat,Lon,Alt,VelN,VelE,VelD,BaroAlt,Flags"),
+	LOG_FORMAT(GPOS, "LLffffff",		"Lat,Lon,Alt,VelN,VelE,VelD,EPH,EPV"),
 	LOG_FORMAT(GPSP, "BLLffBfbf",		"NavState,Lat,Lon,Alt,Yaw,Type,LoitR,LoitDir,PitMin"),
 	LOG_FORMAT(ESC, "HBBBHHHHHHfH",		"count,nESC,Conn,N,Ver,Adr,Volt,Amp,RPM,Temp,SetP,SetPRAW"),
 	LOG_FORMAT(GVSP, "fff",			"VX,VY,VZ"),
diff --git a/src/modules/sensors/sensor_params.c b/src/modules/sensors/sensor_params.c
index a1f2a4ad5..bc49f5c85 100644
--- a/src/modules/sensors/sensor_params.c
+++ b/src/modules/sensors/sensor_params.c
@@ -594,13 +594,13 @@ PARAM_DEFINE_INT32(RC_MAP_RETURN_SW, 0);
 PARAM_DEFINE_INT32(RC_MAP_ASSIST_SW, 0);
 
 /**
- * Mission switch channel mapping.
+ * Loiter switch channel mapping.
  *
  * @min 0
  * @max 18
  * @group Radio Calibration
  */
-PARAM_DEFINE_INT32(RC_MAP_MISSIO_SW, 0);
+PARAM_DEFINE_INT32(RC_MAP_LOITER_SW, 0);
 
 //PARAM_DEFINE_INT32(RC_MAP_OFFB_SW, 0);
 
diff --git a/src/modules/sensors/sensors.cpp b/src/modules/sensors/sensors.cpp
index 3bb8daa0c..e260aae45 100644
--- a/src/modules/sensors/sensors.cpp
+++ b/src/modules/sensors/sensors.cpp
@@ -254,7 +254,7 @@ private:
 		int rc_map_mode_sw;
 		int rc_map_return_sw;
 		int rc_map_assisted_sw;
-		int rc_map_mission_sw;
+		int rc_map_loiter_sw;
 
 //		int rc_map_offboard_ctrl_mode_sw;
 
@@ -297,7 +297,7 @@ private:
 		param_t rc_map_mode_sw;
 		param_t rc_map_return_sw;
 		param_t rc_map_assisted_sw;
-		param_t rc_map_mission_sw;
+		param_t rc_map_loiter_sw;
 
 //		param_t rc_map_offboard_ctrl_mode_sw;
 
@@ -508,7 +508,7 @@ Sensors::Sensors() :
 
 	/* optional mode switches, not mapped per default */
 	_parameter_handles.rc_map_assisted_sw = param_find("RC_MAP_ASSIST_SW");
-	_parameter_handles.rc_map_mission_sw = param_find("RC_MAP_MISSIO_SW");
+	_parameter_handles.rc_map_loiter_sw = param_find("RC_MAP_LOITER_SW");
 
 //	_parameter_handles.rc_map_offboard_ctrl_mode_sw = param_find("RC_MAP_OFFB_SW");
 
@@ -654,7 +654,7 @@ Sensors::parameters_update()
 		warnx("%s", paramerr);
 	}
 
-	if (param_get(_parameter_handles.rc_map_mission_sw, &(_parameters.rc_map_mission_sw)) != OK) {
+	if (param_get(_parameter_handles.rc_map_loiter_sw, &(_parameters.rc_map_loiter_sw)) != OK) {
 		warnx("%s", paramerr);
 	}
 
@@ -682,7 +682,7 @@ Sensors::parameters_update()
 	_rc.function[MODE] = _parameters.rc_map_mode_sw - 1;
 	_rc.function[RETURN] = _parameters.rc_map_return_sw - 1;
 	_rc.function[ASSISTED] = _parameters.rc_map_assisted_sw - 1;
-	_rc.function[MISSION] = _parameters.rc_map_mission_sw - 1;
+	_rc.function[LOITER] = _parameters.rc_map_loiter_sw - 1;
 
 	_rc.function[FLAPS] = _parameters.rc_map_flaps - 1;
 
@@ -1416,7 +1416,7 @@ Sensors::rc_poll()
 			/* mode switches */
 			manual.mode_switch = get_rc_switch_position(MODE);
 			manual.assisted_switch = get_rc_switch_position(ASSISTED);
-			manual.mission_switch = get_rc_switch_position(MISSION);
+			manual.loiter_switch = get_rc_switch_position(LOITER);
 			manual.return_switch = get_rc_switch_position(RETURN);
 
 			/* publish manual_control_setpoint topic */
diff --git a/src/modules/uORB/topics/home_position.h b/src/modules/uORB/topics/home_position.h
index 08d11abae..70071130d 100644
--- a/src/modules/uORB/topics/home_position.h
+++ b/src/modules/uORB/topics/home_position.h
@@ -59,10 +59,13 @@ struct home_position_s
 {
 	uint64_t timestamp;			/**< Timestamp (microseconds since system boot)	*/
 
-	//bool altitude_is_relative;	// TODO what means home relative altitude? we need clear definition of reference altitude then
 	double lat;				/**< Latitude in degrees 			*/
 	double lon;				/**< Longitude in degrees			*/
 	float alt;				/**< Altitude in meters				*/
+
+	float x;				/**< X coordinate in meters			*/
+	float y;				/**< Y coordinate in meters			*/
+	float z;				/**< Z coordinate in meters			*/
 };
 
 /**
diff --git a/src/modules/uORB/topics/manual_control_setpoint.h b/src/modules/uORB/topics/manual_control_setpoint.h
index 2b3a337b2..a23d89cd2 100644
--- a/src/modules/uORB/topics/manual_control_setpoint.h
+++ b/src/modules/uORB/topics/manual_control_setpoint.h
@@ -79,7 +79,7 @@ struct manual_control_setpoint_s {
 	switch_pos_t mode_switch;			/**< mode 3 position switch (mandatory): manual, assisted, auto */
 	switch_pos_t return_switch;			/**< land 2 position switch (mandatory): land, no effect */
 	switch_pos_t assisted_switch;			/**< assisted 2 position switch (optional): seatbelt, simple */
-	switch_pos_t mission_switch;		/**< mission 2 position switch (optional): mission, loiter */
+	switch_pos_t loiter_switch;		/**< mission 2 position switch (optional): mission, loiter */
 }; /**< manual control inputs */
 
 /**
diff --git a/src/modules/uORB/topics/optical_flow.h b/src/modules/uORB/topics/optical_flow.h
index 98f0e3fa2..0196ae86b 100644
--- a/src/modules/uORB/topics/optical_flow.h
+++ b/src/modules/uORB/topics/optical_flow.h
@@ -57,6 +57,7 @@ struct optical_flow_s {
 
 	uint64_t timestamp;		/**< in microseconds since system start          */
 
+	uint64_t flow_timestamp;		/**< timestamp from flow sensor */
 	int16_t flow_raw_x;		/**< flow in pixels in X direction, not rotation-compensated */
 	int16_t flow_raw_y;		/**< flow in pixels in Y direction, not rotation-compensated */
 	float flow_comp_x_m;		/**< speed over ground in meters, rotation-compensated */
diff --git a/src/modules/uORB/topics/rc_channels.h b/src/modules/uORB/topics/rc_channels.h
index 3246a39dd..c168b2fac 100644
--- a/src/modules/uORB/topics/rc_channels.h
+++ b/src/modules/uORB/topics/rc_channels.h
@@ -65,7 +65,7 @@ enum RC_CHANNELS_FUNCTION {
 	MODE = 4,
 	RETURN = 5,
 	ASSISTED = 6,
-	MISSION = 7,
+	LOITER = 7,
 	OFFBOARD_MODE = 8,
 	FLAPS   = 9,
 	AUX_1   = 10,
diff --git a/src/modules/uORB/topics/vehicle_global_position.h b/src/modules/uORB/topics/vehicle_global_position.h
index cfab695f8..e32529cb4 100644
--- a/src/modules/uORB/topics/vehicle_global_position.h
+++ b/src/modules/uORB/topics/vehicle_global_position.h
@@ -61,12 +61,8 @@
  * e.g. control inputs of the vehicle in a Kalman-filter implementation.
  */
 struct vehicle_global_position_s {
-	uint64_t timestamp;		/**< Time of this estimate, in microseconds since system start */
-
-	bool global_valid;		/**< true if position satisfies validity criteria of estimator */
-	bool baro_valid;		/**< true if baro_alt is valid (vel_d is also valid in this case) */
-
-	uint64_t time_gps_usec; 	/**< GPS timestamp in microseconds					   */
+	uint64_t timestamp;		/**< Time of this estimate, in microseconds since system start		*/
+	uint64_t time_gps_usec;		/**< GPS timestamp in microseconds					   */
 	double lat;			/**< Latitude in degrees							 	   */
 	double lon;			/**< Longitude in degrees							 	   */
 	float alt;			/**< Altitude AMSL in meters						 	   */
@@ -74,8 +70,8 @@ struct vehicle_global_position_s {
 	float vel_e;			/**< Ground east velocity, m/s							   */
 	float vel_d;			/**< Ground downside velocity, m/s						   */
 	float yaw; 			/**< Yaw in radians -PI..+PI.							   */
-
-	float baro_alt;			/**< Barometric altitude (not raw baro but fused with accelerometer) */
+	float eph;
+	float epv;
 };
 
 /**
diff --git a/src/modules/uORB/topics/vehicle_local_position.h b/src/modules/uORB/topics/vehicle_local_position.h
index db9637cd9..a15303ea4 100644
--- a/src/modules/uORB/topics/vehicle_local_position.h
+++ b/src/modules/uORB/topics/vehicle_local_position.h
@@ -1,7 +1,6 @@
 /****************************************************************************
  *
  *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
- *   Author: @author Lorenz Meier <lm@inf.ethz.ch>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -35,6 +34,9 @@
 /**
  * @file vehicle_local_position.h
  * Definition of the local fused NED position uORB topic.
+ *
+ * @author Lorenz Meier <lm@inf.ethz.ch>
+ * @author Anton Babushkin <anton.babushkin@me.com>
  */
 
 #ifndef TOPIC_VEHICLE_LOCAL_POSITION_H_
@@ -72,8 +74,8 @@ struct vehicle_local_position_s {
 	bool xy_global;			/**< true if position (x, y) is valid and has valid global reference (ref_lat, ref_lon) */
 	bool z_global;			/**< true if z is valid and has valid global reference (ref_alt) */
 	uint64_t ref_timestamp;	/**< Time when reference position was set */
-	int32_t ref_lat;		/**< Reference point latitude in 1E7 degrees */
-	int32_t ref_lon;		/**< Reference point longitude in 1E7 degrees */
+	double ref_lat;		/**< Reference point latitude in degrees */
+	double ref_lon;		/**< Reference point longitude in degrees */
 	float ref_alt;			/**< Reference altitude AMSL in meters, MUST be set to current (not at reference point!) ground level */
 	bool landed;			/**< true if vehicle is landed */
 	/* Distance to surface */