create empty datalinkloss class for OBC

 Currently the class does the same as the RTL class. It is now possible
 whichclass is sued in the navigator to handle datalink loss via a
 parameter

1 files changed, 317 insertions, 0 deletions

diff --git a/src/modules/navigator/datalinkloss.cpp b/src/modules/navigator/datalinkloss.cpp
new file mode 100644
index 000000000..17e85b284
--- /dev/null
+++ b/src/modules/navigator/datalinkloss.cpp
@@ -0,0 +1,317 @@
+/****************************************************************************
+ *
+ *   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 datalinkloss.cpp
+ * Helper class for Data Link Loss Mode acording to the OBC rules
+ *
+ * @author Thomas Gubler <thomasgubler@gmail.com>
+ */
+
+#include <string.h>
+#include <stdlib.h>
+#include <math.h>
+#include <fcntl.h>
+
+#include <mavlink/mavlink_log.h>
+#include <systemlib/err.h>
+#include <geo/geo.h>
+
+#include <uORB/uORB.h>
+#include <uORB/topics/mission.h>
+#include <uORB/topics/home_position.h>
+
+#include "navigator.h"
+#include "datalinkloss.h"
+
+#define DELAY_SIGMA	0.01f
+
+DataLinkLoss::DataLinkLoss(Navigator *navigator, const char *name) :
+	MissionBlock(navigator, name),
+	_rtl_state(RTL_STATE_NONE),
+	_param_return_alt(this, "RETURN_ALT"),
+	_param_descend_alt(this, "DESCEND_ALT"),
+	_param_land_delay(this, "LAND_DELAY")
+{
+	/* load initial params */
+	updateParams();
+	/* initial reset */
+	on_inactive();
+}
+
+DataLinkLoss::~DataLinkLoss()
+{
+}
+
+void
+DataLinkLoss::on_inactive()
+{
+	/* reset RTL state only if setpoint moved */
+	if (!_navigator->get_can_loiter_at_sp()) {
+		_rtl_state = RTL_STATE_NONE;
+	}
+}
+
+void
+DataLinkLoss::on_activation()
+{
+	/* decide where to enter the RTL procedure when we switch into it */
+	if (_rtl_state == RTL_STATE_NONE) {
+		/* for safety reasons don't go into RTL if landed */
+		if (_navigator->get_vstatus()->condition_landed) {
+			_rtl_state = RTL_STATE_LANDED;
+			mavlink_log_info(_navigator->get_mavlink_fd(), "#audio: no RTL when landed");
+
+		/* if lower than return altitude, climb up first */
+		} else if (_navigator->get_global_position()->alt < _navigator->get_home_position()->alt
+			   + _param_return_alt.get()) {
+			_rtl_state = RTL_STATE_CLIMB;
+
+		/* otherwise go straight to return */
+		} else {
+			/* set altitude setpoint to current altitude */
+			_rtl_state = RTL_STATE_RETURN;
+			_mission_item.altitude_is_relative = false;
+			_mission_item.altitude = _navigator->get_global_position()->alt;
+		}
+	}
+
+	set_rtl_item();
+}
+
+void
+DataLinkLoss::on_active()
+{
+	if (_rtl_state != RTL_STATE_LANDED && is_mission_item_reached()) {
+		advance_rtl();
+		set_rtl_item();
+	}
+}
+
+void
+DataLinkLoss::set_rtl_item()
+{
+	struct position_setpoint_triplet_s *pos_sp_triplet = _navigator->get_position_setpoint_triplet();
+
+	/* make sure we have the latest params */
+	updateParams();
+
+	set_previous_pos_setpoint();
+	_navigator->set_can_loiter_at_sp(false);
+
+	switch (_rtl_state) {
+	case RTL_STATE_CLIMB: {
+		float climb_alt = _navigator->get_home_position()->alt + _param_return_alt.get();
+
+		_mission_item.lat = _navigator->get_global_position()->lat;
+		_mission_item.lon = _navigator->get_global_position()->lon;
+		_mission_item.altitude_is_relative = false;
+		_mission_item.altitude = climb_alt;
+		_mission_item.yaw = NAN;
+		_mission_item.loiter_radius = _navigator->get_loiter_radius();
+		_mission_item.loiter_direction = 1;
+		_mission_item.nav_cmd = NAV_CMD_WAYPOINT;
+		_mission_item.acceptance_radius = _navigator->get_acceptance_radius();
+		_mission_item.time_inside = 0.0f;
+		_mission_item.pitch_min = 0.0f;
+		_mission_item.autocontinue = true;
+		_mission_item.origin = ORIGIN_ONBOARD;
+
+		mavlink_log_info(_navigator->get_mavlink_fd(), "#audio: RTL: climb to %d meters above home",
+			(int)(climb_alt - _navigator->get_home_position()->alt));
+		break;
+	}
+
+	case RTL_STATE_RETURN: {
+		_mission_item.lat = _navigator->get_home_position()->lat;
+		_mission_item.lon = _navigator->get_home_position()->lon;
+		 // don't change altitude
+
+		 if (pos_sp_triplet->previous.valid) {
+		 	/* if previous setpoint is valid then use it to calculate heading to home */
+		 	_mission_item.yaw = get_bearing_to_next_waypoint(
+		 	        pos_sp_triplet->previous.lat, pos_sp_triplet->previous.lon,
+		 	        _mission_item.lat, _mission_item.lon);
+
+		 } else {
+		 	/* else use current position */
+		 	_mission_item.yaw = get_bearing_to_next_waypoint(
+		 	        _navigator->get_global_position()->lat, _navigator->get_global_position()->lon,
+		 	        _mission_item.lat, _mission_item.lon);
+		 }
+		_mission_item.loiter_radius = _navigator->get_loiter_radius();
+		_mission_item.loiter_direction = 1;
+		_mission_item.nav_cmd = NAV_CMD_WAYPOINT;
+		_mission_item.acceptance_radius = _navigator->get_acceptance_radius();
+		_mission_item.time_inside = 0.0f;
+		_mission_item.pitch_min = 0.0f;
+		_mission_item.autocontinue = true;
+		_mission_item.origin = ORIGIN_ONBOARD;
+
+		mavlink_log_info(_navigator->get_mavlink_fd(), "#audio: RTL: return at %d meters above home",
+			(int)(_mission_item.altitude - _navigator->get_home_position()->alt));
+		break;
+	}
+
+	case RTL_STATE_DESCEND: {
+		_mission_item.lat = _navigator->get_home_position()->lat;
+		_mission_item.lon = _navigator->get_home_position()->lon;
+		_mission_item.altitude_is_relative = false;
+		_mission_item.altitude = _navigator->get_home_position()->alt + _param_descend_alt.get();
+		_mission_item.yaw = NAN;
+		_mission_item.loiter_radius = _navigator->get_loiter_radius();
+		_mission_item.loiter_direction = 1;
+		_mission_item.nav_cmd = NAV_CMD_LOITER_TIME_LIMIT;
+		_mission_item.acceptance_radius = _navigator->get_acceptance_radius();
+		_mission_item.time_inside = 0.0f;
+		_mission_item.pitch_min = 0.0f;
+		_mission_item.autocontinue = false;
+		_mission_item.origin = ORIGIN_ONBOARD;
+
+		mavlink_log_info(_navigator->get_mavlink_fd(), "#audio: RTL: descend to %d meters above home",
+			(int)(_mission_item.altitude - _navigator->get_home_position()->alt));
+		break;
+	}
+
+	case RTL_STATE_LOITER: {
+		bool autoland = _param_land_delay.get() > -DELAY_SIGMA;
+
+		_mission_item.lat = _navigator->get_home_position()->lat;
+		_mission_item.lon = _navigator->get_home_position()->lon;
+		_mission_item.altitude_is_relative = false;
+		_mission_item.altitude = _navigator->get_home_position()->alt + _param_descend_alt.get();
+		_mission_item.yaw = NAN;
+		_mission_item.loiter_radius = _navigator->get_loiter_radius();
+		_mission_item.loiter_direction = 1;
+		_mission_item.nav_cmd = autoland ? NAV_CMD_LOITER_TIME_LIMIT : NAV_CMD_LOITER_UNLIMITED;
+		_mission_item.acceptance_radius = _navigator->get_acceptance_radius();
+		_mission_item.time_inside = _param_land_delay.get() < 0.0f ? 0.0f : _param_land_delay.get();
+		_mission_item.pitch_min = 0.0f;
+		_mission_item.autocontinue = autoland;
+		_mission_item.origin = ORIGIN_ONBOARD;
+
+		_navigator->set_can_loiter_at_sp(true);
+
+		if (autoland) {
+			mavlink_log_info(_navigator->get_mavlink_fd(), "#audio: RTL: loiter %.1fs", (double)_mission_item.time_inside);
+
+		} else {
+			mavlink_log_info(_navigator->get_mavlink_fd(), "#audio: RTL: completed, loiter");
+		}
+		break;
+	}
+
+	case RTL_STATE_LAND: {
+		_mission_item.lat = _navigator->get_home_position()->lat;
+		_mission_item.lon = _navigator->get_home_position()->lon;
+		_mission_item.altitude_is_relative = false;
+		_mission_item.altitude = _navigator->get_home_position()->alt;
+		_mission_item.yaw = NAN;
+		_mission_item.loiter_radius = _navigator->get_loiter_radius();
+		_mission_item.loiter_direction = 1;
+		_mission_item.nav_cmd = NAV_CMD_LAND;
+		_mission_item.acceptance_radius = _navigator->get_acceptance_radius();
+		_mission_item.time_inside = 0.0f;
+		_mission_item.pitch_min = 0.0f;
+		_mission_item.autocontinue = true;
+		_mission_item.origin = ORIGIN_ONBOARD;
+
+		mavlink_log_info(_navigator->get_mavlink_fd(), "#audio: RTL: land at home");
+		break;
+	}
+
+	case RTL_STATE_LANDED: {
+		_mission_item.lat = _navigator->get_home_position()->lat;
+		_mission_item.lon = _navigator->get_home_position()->lon;
+		_mission_item.altitude_is_relative = false;
+		_mission_item.altitude = _navigator->get_home_position()->alt;
+		_mission_item.yaw = NAN;
+		_mission_item.loiter_radius = _navigator->get_loiter_radius();
+		_mission_item.loiter_direction = 1;
+		_mission_item.nav_cmd = NAV_CMD_IDLE;
+		_mission_item.acceptance_radius = _navigator->get_acceptance_radius();
+		_mission_item.time_inside = 0.0f;
+		_mission_item.pitch_min = 0.0f;
+		_mission_item.autocontinue = true;
+		_mission_item.origin = ORIGIN_ONBOARD;
+
+		mavlink_log_info(_navigator->get_mavlink_fd(), "#audio: RTL: completed, landed");
+		break;
+	}
+
+	default:
+		break;
+	}
+
+	reset_mission_item_reached();
+
+	/* convert mission item to current position setpoint and make it valid */
+	mission_item_to_position_setpoint(&_mission_item, &pos_sp_triplet->current);
+	pos_sp_triplet->next.valid = false;
+
+	_navigator->set_position_setpoint_triplet_updated();
+}
+
+void
+DataLinkLoss::advance_rtl()
+{
+	switch (_rtl_state) {
+	case RTL_STATE_CLIMB:
+		_rtl_state = RTL_STATE_RETURN;
+		break;
+
+	case RTL_STATE_RETURN:
+		_rtl_state = RTL_STATE_DESCEND;
+		break;
+
+	case RTL_STATE_DESCEND:
+		/* only go to land if autoland is enabled */
+		if (_param_land_delay.get() < -DELAY_SIGMA || _param_land_delay.get() > DELAY_SIGMA) {
+			_rtl_state = RTL_STATE_LOITER;
+
+		} else {
+			_rtl_state = RTL_STATE_LAND;
+		}
+		break;
+
+	case RTL_STATE_LOITER:
+		_rtl_state = RTL_STATE_LAND;
+		break;
+
+	case RTL_STATE_LAND:
+		_rtl_state = RTL_STATE_LANDED;
+		break;
+
+	default:
+		break;
+	}
+}