Merge remote-tracking branch 'upstream/master' into obcfailsafe

Conflicts:
	src/modules/fw_pos_control_l1/fw_pos_control_l1_main.cpp

2 files changed, 20 insertions, 5 deletions

diff --git a/src/modules/fw_pos_control_l1/fw_pos_control_l1_main.cpp b/src/modules/fw_pos_control_l1/fw_pos_control_l1_main.cpp
index 0c35ccb2c..5d62c90ab 100644
--- a/src/modules/fw_pos_control_l1/fw_pos_control_l1_main.cpp
+++ b/src/modules/fw_pos_control_l1/fw_pos_control_l1_main.cpp
@@ -578,6 +578,12 @@ FixedwingPositionControl::parameters_update()
 	param_get(_parameter_handles.land_H1_virt, &(_parameters.land_H1_virt));
 	param_get(_parameter_handles.land_flare_alt_relative, &(_parameters.land_flare_alt_relative));
 	param_get(_parameter_handles.land_thrust_lim_alt_relative, &(_parameters.land_thrust_lim_alt_relative));
+
+	/* check if negative value for 2/3 of flare altitude is set for throttle cut */
+	if (_parameters.land_thrust_lim_alt_relative < 0.0f) {
+		_parameters.land_thrust_lim_alt_relative = 0.66f * _parameters.land_flare_alt_relative;
+	}
+
 	param_get(_parameter_handles.land_heading_hold_horizontal_distance, &(_parameters.land_heading_hold_horizontal_distance));
 
 	param_get(_parameter_handles.range_finder_rel_alt, &(_parameters.range_finder_rel_alt));
@@ -843,7 +849,7 @@ float FixedwingPositionControl::get_relative_landingalt(float land_setpoint_alt,
 	 * the measurement is valid
 	 * the estimated relative altitude (from global altitude estimate and landing waypoint) <= range_finder_use_relative_alt
 	 */
-	if (range_finder_use_relative_alt < 0 || !range_finder.valid || rel_alt_estimated > range_finder_use_relative_alt ) {
+	if (range_finder_use_relative_alt < 0 || !range_finder.valid || range_finder.distance > range_finder_use_relative_alt ) {
 		return rel_alt_estimated;
 	}
 
@@ -1419,6 +1425,10 @@ void FixedwingPositionControl::tecs_update_pitch_throttle(float alt_sp, float v_
 			pitch_min_rad = M_DEG_TO_RAD_F * -1.0f;
 			pitch_max_rad = M_DEG_TO_RAD_F * 5.0f;
 		}
+
+/* No underspeed protection in landing mode */
+		_tecs.set_detect_underspeed_enabled(!(mode == TECS_MODE_LAND || mode == TECS_MODE_LAND_THROTTLELIM));
+
 		/* Using tecs library */
 		_tecs.update_pitch_throttle(_R_nb, _att.pitch, altitude, alt_sp, v_sp,
 					    _airspeed.indicated_airspeed_m_s, eas2tas,
diff --git a/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c b/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c
index 41c374407..890ab3bad 100644
--- a/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c
+++ b/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c
@@ -379,18 +379,23 @@ PARAM_DEFINE_FLOAT(FW_LND_ANG, 5.0f);
 PARAM_DEFINE_FLOAT(FW_LND_HVIRT, 10.0f);
 
 /**
- * Landing flare altitude (relative)
+ * Landing flare altitude (relative to landing altitude)
  *
+ * @unit meter
  * @group L1 Control
  */
-PARAM_DEFINE_FLOAT(FW_LND_FLALT, 15.0f);
+PARAM_DEFINE_FLOAT(FW_LND_FLALT, 8.0f);
 
 /**
- * Landing throttle limit altitude (relative)
+ * Landing throttle limit altitude (relative landing altitude)
  *
+ * Default of -1.0f lets the system default to applying throttle
+ * limiting at 2/3 of the flare altitude.
+ *
+ * @unit meter
  * @group L1 Control
  */
-PARAM_DEFINE_FLOAT(FW_LND_TLALT, 5.0f);
+PARAM_DEFINE_FLOAT(FW_LND_TLALT, -1.0f);
 
 /**
  * Landing heading hold horizontal distance