bizhang_-obav/src/modules/navigator/mission_block.cpp

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/**
 * @file mission_block.cpp
 *
 * Helper class to use mission items
 *
 * @author Julian Oes <julian@oes.ch>
 * @author Sander Smeets <sander@droneslab.com>
 * @author Andreas Antener <andreas@uaventure.com>
 */

#include "mission_block.h"
#include "navigator.h"

#include <math.h>
#include <float.h>

#include <geo/geo.h>
#include <systemlib/mavlink_log.h>
#include <mathlib/mathlib.h>
#include <uORB/uORB.h>
#include <uORB/topics/actuator_controls.h>
#include <uORB/topics/vehicle_command.h>
#include <uORB/topics/vtol_vehicle_status.h>



MissionBlock::MissionBlock(Navigator *navigator, const char *name) :
	NavigatorMode(navigator, name),
	_param_loiter_min_alt(this, "MIS_LTRMIN_ALT", false),
	_param_yaw_timeout(this, "MIS_YAW_TMT", false),
	_param_yaw_err(this, "MIS_YAW_ERR", false),
	_param_vtol_wv_land(this, "VT_WV_LND_EN", false),
	_param_vtol_wv_takeoff(this, "VT_WV_TKO_EN", false),
	_param_vtol_wv_loiter(this, "VT_WV_LTR_EN", false),
	_param_force_vtol(this, "NAV_FORCE_VT", false),
	_param_back_trans_dur(this, "VT_B_TRANS_DUR", false)
{
}

bool
MissionBlock::is_mission_item_reached()
{
	/* handle non-navigation or indefinite waypoints */

	switch (_mission_item.nav_cmd) {
	case NAV_CMD_DO_SET_SERVO:
		return true;

	case NAV_CMD_LAND: /* fall through */
	case NAV_CMD_VTOL_LAND:
		return _navigator->get_land_detected()->landed;

	case NAV_CMD_IDLE: /* fall through */
	case NAV_CMD_LOITER_UNLIMITED:
		return false;

	case NAV_CMD_DO_LAND_START:
	case NAV_CMD_DO_TRIGGER_CONTROL:
	case NAV_CMD_DO_DIGICAM_CONTROL:
	case NAV_CMD_IMAGE_START_CAPTURE:
	case NAV_CMD_IMAGE_STOP_CAPTURE:
	case NAV_CMD_VIDEO_START_CAPTURE:
	case NAV_CMD_VIDEO_STOP_CAPTURE:
	case NAV_CMD_DO_MOUNT_CONFIGURE:
	case NAV_CMD_DO_MOUNT_CONTROL:
	case NAV_CMD_DO_SET_ROI:
	case NAV_CMD_ROI:
	case NAV_CMD_DO_SET_CAM_TRIGG_DIST:
	case NAV_CMD_DO_SET_CAM_TRIGG_INTERVAL:
	case NAV_CMD_SET_CAMERA_MODE:
		return true;

	case NAV_CMD_DO_VTOL_TRANSITION:

		/*
		 * We wait half a second to give the transition command time to propagate.
		 * Then monitor the transition status for completion.
		 */
		// TODO: check desired transition state achieved and drop _action_start
		if (hrt_absolute_time() - _action_start > 500000 &&
		    !_navigator->get_vstatus()->in_transition_mode) {

			_action_start = 0;
			return true;

		} else {
			return false;
		}

	case NAV_CMD_DO_CHANGE_SPEED:
		return true;

	default:
		/* do nothing, this is a 3D waypoint */
		break;
	}

	hrt_abstime now = hrt_absolute_time();

	if (!_navigator->get_land_detected()->landed && !_waypoint_position_reached) {

		float dist = -1.0f;
		float dist_xy = -1.0f;
		float dist_z = -1.0f;

		float altitude_amsl = _mission_item.altitude_is_relative
				      ? _mission_item.altitude + _navigator->get_home_position()->alt
				      : _mission_item.altitude;

		dist = get_distance_to_point_global_wgs84(_mission_item.lat, _mission_item.lon, altitude_amsl,
				_navigator->get_global_position()->lat,
				_navigator->get_global_position()->lon,
				_navigator->get_global_position()->alt,
				&dist_xy, &dist_z);

		/* FW special case for NAV_CMD_WAYPOINT to achieve altitude via loiter */
		if (!_navigator->get_vstatus()->is_rotary_wing &&
		    (_mission_item.nav_cmd == NAV_CMD_WAYPOINT)) {

			struct position_setpoint_s *curr_sp = &_navigator->get_position_setpoint_triplet()->current;

			/* close to waypoint, but altitude error greater than twice acceptance */
			if ((dist >= 0.0f)
			    && (dist_z > 2 * _navigator->get_altitude_acceptance_radius())
			    && (dist_xy < 2 * _navigator->get_loiter_radius())) {

				/* SETPOINT_TYPE_POSITION -> SETPOINT_TYPE_LOITER */
				if (curr_sp->type == position_setpoint_s::SETPOINT_TYPE_POSITION) {
					curr_sp->type = position_setpoint_s::SETPOINT_TYPE_LOITER;
					curr_sp->loiter_radius = _navigator->get_loiter_radius();
					curr_sp->loiter_direction = 1;
					_navigator->set_position_setpoint_triplet_updated();
				}

			} else {
				/* restore SETPOINT_TYPE_POSITION */
				if (curr_sp->type == position_setpoint_s::SETPOINT_TYPE_LOITER) {
					/* loiter acceptance criteria required to revert back to SETPOINT_TYPE_POSITION */
					if ((dist >= 0.0f)
					    && (dist_z < _navigator->get_loiter_radius())
					    && (dist_xy <= _navigator->get_loiter_radius() * 1.2f)) {

						curr_sp->type = position_setpoint_s::SETPOINT_TYPE_POSITION;
						_navigator->set_position_setpoint_triplet_updated();
					}
				}
			}
		}

		if ((_mission_item.nav_cmd == NAV_CMD_TAKEOFF || _mission_item.nav_cmd == NAV_CMD_VTOL_TAKEOFF)
		    && _navigator->get_vstatus()->is_rotary_wing) {

			/* We want to avoid the edge case where the acceptance radius is bigger or equal than
			 * the altitude of the takeoff waypoint above home. Otherwise, we do not really follow
			 * take-off procedures like leaving the landing gear down. */

			float takeoff_alt = _mission_item.altitude_is_relative ?
					    _mission_item.altitude :
					    (_mission_item.altitude - _navigator->get_home_position()->alt);

			float altitude_acceptance_radius = _navigator->get_altitude_acceptance_radius();

			/* It should be safe to just use half of the takoeff_alt as an acceptance radius. */
			if (takeoff_alt > 0 && takeoff_alt < altitude_acceptance_radius) {
				altitude_acceptance_radius = takeoff_alt / 2.0f;
			}

			/* require only altitude for takeoff for multicopter */
			if (_navigator->get_global_position()->alt >
			    altitude_amsl - altitude_acceptance_radius) {
				_waypoint_position_reached = true;
			}

		} else if (_mission_item.nav_cmd == NAV_CMD_TAKEOFF) {
			/* for takeoff mission items use the parameter for the takeoff acceptance radius */
			if (dist >= 0.0f && dist <= _navigator->get_acceptance_radius()
			    && dist_z <= _navigator->get_altitude_acceptance_radius()) {
				_waypoint_position_reached = true;
			}

		} else if (!_navigator->get_vstatus()->is_rotary_wing &&
			   (_mission_item.nav_cmd == NAV_CMD_LOITER_UNLIMITED ||
			    _mission_item.nav_cmd == NAV_CMD_LOITER_TIME_LIMIT)) {
			/* Loiter mission item on a non rotary wing: the aircraft is going to circle the
			 * coordinates with a radius equal to the loiter_radius field. It is not flying
			 * through the waypoint center.
			 * Therefore the item is marked as reached once the system reaches the loiter
			 * radius (+ some margin). Time inside and turn count is handled elsewhere.
			 */
			if (dist >= 0.0f && dist <= _navigator->get_acceptance_radius(fabsf(_mission_item.loiter_radius) * 1.2f)
			    && dist_z <= _navigator->get_altitude_acceptance_radius()) {

				_waypoint_position_reached = true;

			} else {
				_time_first_inside_orbit = 0;
			}

		} else if (!_navigator->get_vstatus()->is_rotary_wing &&
			   (_mission_item.nav_cmd == NAV_CMD_LOITER_TO_ALT)) {


			// NAV_CMD_LOITER_TO_ALT only uses mission item altitude once it's in the loiter
			//  first check if the altitude setpoint is the mission setpoint
			struct position_setpoint_s *curr_sp = &_navigator->get_position_setpoint_triplet()->current;

			if (fabsf(curr_sp->alt - altitude_amsl) >= FLT_EPSILON) {
				// check if the initial loiter has been accepted
				dist_xy = -1.0f;
				dist_z = -1.0f;

				dist = get_distance_to_point_global_wgs84(_mission_item.lat, _mission_item.lon, curr_sp->alt,
						_navigator->get_global_position()->lat,
						_navigator->get_global_position()->lon,
						_navigator->get_global_position()->alt,
						&dist_xy, &dist_z);

				if (dist >= 0.0f && dist <= _navigator->get_acceptance_radius(fabsf(_mission_item.loiter_radius) * 1.2f)
				    && dist_z <= _navigator->get_altitude_acceptance_radius()) {

					// now set the loiter to the final altitude in the NAV_CMD_LOITER_TO_ALT mission item
					curr_sp->alt = altitude_amsl;
					_navigator->set_position_setpoint_triplet_updated();
				}

			} else {
				if (dist >= 0.0f && dist <= _navigator->get_acceptance_radius(fabsf(_mission_item.loiter_radius) * 1.2f)
				    && dist_z <= _navigator->get_altitude_acceptance_radius()) {

					_waypoint_position_reached = true;

					// set required yaw from bearing to the next mission item
					if (_mission_item.force_heading) {
						struct position_setpoint_s next_sp = _navigator->get_position_setpoint_triplet()->next;

						if (next_sp.valid) {
							_mission_item.yaw = get_bearing_to_next_waypoint(_navigator->get_global_position()->lat,
									    _navigator->get_global_position()->lon,
									    next_sp.lat, next_sp.lon);

							_waypoint_yaw_reached = false;

						} else {
							_waypoint_yaw_reached = true;
						}
					}
				}
			}

		} else if (_mission_item.nav_cmd == NAV_CMD_DELAY) {
			_waypoint_position_reached = true;
			_waypoint_yaw_reached = true;
			_time_wp_reached = now;

		} else {
			/* for normal mission items used their acceptance radius */
			float mission_acceptance_radius = _navigator->get_acceptance_radius(_mission_item.acceptance_radius);

			/* if set to zero use the default instead */
			if (mission_acceptance_radius < NAV_EPSILON_POSITION) {
				mission_acceptance_radius = _navigator->get_acceptance_radius();
			}

			/* for vtol back transition calculate acceptance radius based on time and ground speed */
			if (_mission_item.vtol_back_transition) {

				float groundspeed = sqrtf(_navigator->get_global_position()->vel_n * _navigator->get_global_position()->vel_n +
							  _navigator->get_global_position()->vel_e * _navigator->get_global_position()->vel_e);

				if (_param_back_trans_dur.get() > FLT_EPSILON && groundspeed > FLT_EPSILON
				    && groundspeed * _param_back_trans_dur.get() > mission_acceptance_radius) {
					mission_acceptance_radius = groundspeed * _param_back_trans_dur.get();
				}

			}

			if (dist >= 0.0f && dist <= mission_acceptance_radius
			    && dist_z <= _navigator->get_altitude_acceptance_radius()) {
				_waypoint_position_reached = true;
			}
		}

		if (_waypoint_position_reached) {
			// reached just now
			_time_wp_reached = now;
		}
	}

	/* Check if the waypoint and the requested yaw setpoint. */

	if (_waypoint_position_reached && !_waypoint_yaw_reached) {

		if ((_navigator->get_vstatus()->is_rotary_wing
		     || (_mission_item.nav_cmd == NAV_CMD_LOITER_TO_ALT && _mission_item.force_heading))
		    && PX4_ISFINITE(_mission_item.yaw)) {

			/* check course if defined only for rotary wing except takeoff */
			float cog = _navigator->get_vstatus()->is_rotary_wing ? _navigator->get_global_position()->yaw : atan2f(
					    _navigator->get_global_position()->vel_e,
					    _navigator->get_global_position()->vel_n);
			float yaw_err = _wrap_pi(_mission_item.yaw - cog);

			/* accept yaw if reached or if timeout is set in which case we ignore not forced headings */
			if (fabsf(yaw_err) < math::radians(_param_yaw_err.get())
			    || (_param_yaw_timeout.get() >= FLT_EPSILON && !_mission_item.force_heading)) {

				_waypoint_yaw_reached = true;
			}

			/* if heading needs to be reached, the timeout is enabled and we don't make it, abort mission */
			if (!_waypoint_yaw_reached && _mission_item.force_heading &&
			    (_param_yaw_timeout.get() >= FLT_EPSILON) &&
			    (now - _time_wp_reached >= (hrt_abstime)_param_yaw_timeout.get() * 1e6f)) {

				_navigator->set_mission_failure("unable to reach heading within timeout");
			}

		} else {
			_waypoint_yaw_reached = true;
		}
	}

	/* Once the waypoint and yaw setpoint have been reached we can start the loiter time countdown */
	if (_waypoint_position_reached && _waypoint_yaw_reached) {

		if (_time_first_inside_orbit == 0) {
			_time_first_inside_orbit = now;
		}

		/* check if the MAV was long enough inside the waypoint orbit */
		if ((get_time_inside(_mission_item) < FLT_EPSILON) ||
		    (now - _time_first_inside_orbit >= (hrt_abstime)(get_time_inside(_mission_item) * 1e6f))) {

			// exit xtrack location
			if (_mission_item.loiter_exit_xtrack &&
			    (_mission_item.nav_cmd == NAV_CMD_LOITER_TIME_LIMIT ||
			     _mission_item.nav_cmd == NAV_CMD_LOITER_TO_ALT)) {

				// reset lat/lon of loiter waypoint so vehicle follows a tangent
				struct position_setpoint_s *curr_sp = &_navigator->get_position_setpoint_triplet()->current;
				const struct position_setpoint_s *next_sp = &_navigator->get_position_setpoint_triplet()->next;
				float range = get_distance_to_next_waypoint(curr_sp->lat, curr_sp->lon, next_sp->lat, next_sp->lon);
				float bearing = get_bearing_to_next_waypoint(curr_sp->lat, curr_sp->lon, next_sp->lat, next_sp->lon);
				float inner_angle = M_PI_2_F - asinf(_mission_item.loiter_radius / range);

				// Compute "ideal" tangent origin
				if (curr_sp->loiter_direction > 0) {
					bearing -= inner_angle;

				} else {
					bearing += inner_angle;
				}


				// Replace current setpoint lat/lon with tangent coordinate
				waypoint_from_heading_and_distance(curr_sp->lat, curr_sp->lon,
								   bearing, curr_sp->loiter_radius,
								   &curr_sp->lat, &curr_sp->lon);
			}

			return true;
		}
	}

	// all acceptance criteria must be met in the same iteration
	_waypoint_position_reached = false;
	_waypoint_yaw_reached = false;
	return false;
}

void
MissionBlock::reset_mission_item_reached()
{
	_waypoint_position_reached = false;
	_waypoint_yaw_reached = false;
	_time_first_inside_orbit = 0;
	_time_wp_reached = 0;
}

void
MissionBlock::mission_item_to_vehicle_command(const struct mission_item_s *item, struct vehicle_command_s *cmd)
{
	// we're expecting a mission command item here so assign the "raw" inputs to the command
	// (MAV_FRAME_MISSION mission item)
	cmd->param1 = item->params[0];
	cmd->param2 = item->params[1];
	cmd->param3 = item->params[2];
	cmd->param4 = item->params[3];
	cmd->param5 = item->params[4];
	cmd->param6 = item->params[5];
	cmd->param7 = item->params[6];
	cmd->command = item->nav_cmd;

	cmd->target_system = _navigator->get_vstatus()->system_id;

	// The camera commands are not processed on the autopilot but will be
	// sent to the mavlink links to other components.
	switch (item->nav_cmd) {
	case NAV_CMD_IMAGE_START_CAPTURE:
	case NAV_CMD_IMAGE_STOP_CAPTURE:
	case NAV_CMD_VIDEO_START_CAPTURE:
	case NAV_CMD_VIDEO_STOP_CAPTURE:
		cmd->target_component = 100; // MAV_COMP_ID_CAMERA
		break;

	default:
		cmd->target_component = _navigator->get_vstatus()->component_id;
		break;
	}

	cmd->source_system = _navigator->get_vstatus()->system_id;
	cmd->source_component = _navigator->get_vstatus()->component_id;
	cmd->confirmation = false;
}

void
MissionBlock::issue_command(const struct mission_item_s *item)
{

	if (item_contains_position(item)) {
		return;
	}

	// NAV_CMD_DO_LAND_START is only a marker
	if (item->nav_cmd == NAV_CMD_DO_LAND_START) {
		return;
	}

	if (item->nav_cmd == NAV_CMD_DO_SET_SERVO) {
		PX4_INFO("do_set_servo command");
		// XXX: we should issue a vehicle command and handle this somewhere else
		_actuators = {};
		// params[0] actuator number to be set 0..5 (corresponds to AUX outputs 1..6)
		// params[1] new value for selected actuator in ms 900...2000
		_actuators.control[(int)item->params[0]] = 1.0f / 2000 * -item->params[1];
		_actuators.timestamp = hrt_absolute_time();

		if (_actuator_pub != nullptr) {
			orb_publish(ORB_ID(actuator_controls_2), _actuator_pub, &_actuators);

		} else {
			_actuator_pub = orb_advertise(ORB_ID(actuator_controls_2), &_actuators);
		}

	} else {
		PX4_INFO("forwarding command %d", item->nav_cmd);
		struct vehicle_command_s cmd = {};
		mission_item_to_vehicle_command(item, &cmd);
		_action_start = hrt_absolute_time();

		_navigator->publish_vehicle_cmd(cmd);
	}
}

float
MissionBlock::get_time_inside(const struct mission_item_s &item)
{
	if (item.nav_cmd != NAV_CMD_TAKEOFF) {
		return item.time_inside;
	}

	return 0.0f;
}

bool
MissionBlock::item_contains_position(const struct mission_item_s *item)
{
	return item->nav_cmd == NAV_CMD_WAYPOINT ||
	       item->nav_cmd == NAV_CMD_LOITER_UNLIMITED ||
	       item->nav_cmd == NAV_CMD_LOITER_TIME_LIMIT ||
	       item->nav_cmd == NAV_CMD_LAND ||
	       item->nav_cmd == NAV_CMD_TAKEOFF ||
	       item->nav_cmd == NAV_CMD_LOITER_TO_ALT ||
	       item->nav_cmd == NAV_CMD_VTOL_TAKEOFF ||
	       item->nav_cmd == NAV_CMD_VTOL_LAND;
}

void
MissionBlock::mission_item_to_position_setpoint(const struct mission_item_s *item, struct position_setpoint_s *sp)
{
	/* don't change the setpoint for non-position items */
	if (!item_contains_position(item)) {
		return;
	}

	sp->lat = item->lat;
	sp->lon = item->lon;
	sp->alt = item->altitude_is_relative ? item->altitude + _navigator->get_home_position()->alt : item->altitude;
	sp->yaw = item->yaw;
	sp->yaw_valid = PX4_ISFINITE(item->yaw);
	sp->loiter_radius = (fabsf(item->loiter_radius) > NAV_EPSILON_POSITION) ? fabsf(item->loiter_radius) :
			    _navigator->get_loiter_radius();
	sp->loiter_direction = (item->loiter_radius > 0) ? 1 : -1;
	sp->acceptance_radius = item->acceptance_radius;
	sp->disable_mc_yaw_control = item->disable_mc_yaw;

	sp->cruising_speed = _navigator->get_cruising_speed();
	sp->cruising_throttle = _navigator->get_cruising_throttle();

	switch (item->nav_cmd) {
	case NAV_CMD_IDLE:
		sp->type = position_setpoint_s::SETPOINT_TYPE_IDLE;
		break;

	case NAV_CMD_TAKEOFF:

		// if already flying (armed and !landed) treat TAKEOFF like regular POSITION
		if ((_navigator->get_vstatus()->arming_state == vehicle_status_s::ARMING_STATE_ARMED)
		    && !_navigator->get_land_detected()->landed) {

			sp->type = position_setpoint_s::SETPOINT_TYPE_POSITION;

		} else {
			sp->type = position_setpoint_s::SETPOINT_TYPE_TAKEOFF;

			// set pitch and ensure that the hold time is zero
			sp->pitch_min = item->pitch_min;
		}

		break;

	case NAV_CMD_VTOL_TAKEOFF:
		sp->type = position_setpoint_s::SETPOINT_TYPE_TAKEOFF;

		if (_navigator->get_vstatus()->is_vtol && _param_vtol_wv_takeoff.get()) {
			sp->disable_mc_yaw_control = true;
		}

		break;

	case NAV_CMD_LAND:
	case NAV_CMD_VTOL_LAND:
		sp->type = position_setpoint_s::SETPOINT_TYPE_LAND;

		if (_navigator->get_vstatus()->is_vtol && _param_vtol_wv_land.get()) {
			sp->disable_mc_yaw_control = true;
		}

		break;

	case NAV_CMD_LOITER_TO_ALT:
		// initially use current altitude, and switch to mission item altitude once in loiter position
		sp->alt = math::max(_navigator->get_global_position()->alt,
				    _navigator->get_home_position()->alt + _param_loiter_min_alt.get());

	// fall through
	case NAV_CMD_LOITER_TIME_LIMIT:
	case NAV_CMD_LOITER_UNLIMITED:
		sp->type = position_setpoint_s::SETPOINT_TYPE_LOITER;

		if (_navigator->get_vstatus()->is_vtol && _param_vtol_wv_loiter.get()) {
			sp->disable_mc_yaw_control = true;
		}

		break;

	default:
		sp->type = position_setpoint_s::SETPOINT_TYPE_POSITION;
		break;
	}

	sp->valid = true;
}

void
MissionBlock::set_previous_pos_setpoint()
{
	struct position_setpoint_triplet_s *pos_sp_triplet = _navigator->get_position_setpoint_triplet();

	if (pos_sp_triplet->current.valid) {
		memcpy(&pos_sp_triplet->previous, &pos_sp_triplet->current, sizeof(struct position_setpoint_s));
	}
}

void
MissionBlock::set_loiter_item(struct mission_item_s *item, float min_clearance)
{
	if (_navigator->get_land_detected()->landed) {
		/* landed, don't takeoff, but switch to IDLE mode */
		item->nav_cmd = NAV_CMD_IDLE;

	} else {
		item->nav_cmd = NAV_CMD_LOITER_UNLIMITED;

		struct position_setpoint_triplet_s *pos_sp_triplet = _navigator->get_position_setpoint_triplet();

		if (_navigator->get_can_loiter_at_sp() && pos_sp_triplet->current.valid) {
			/* use current position setpoint */
			item->lat = pos_sp_triplet->current.lat;
			item->lon = pos_sp_triplet->current.lon;
			item->altitude = pos_sp_triplet->current.alt;

		} else {
			/* use current position and use return altitude as clearance */
			item->lat = _navigator->get_global_position()->lat;
			item->lon = _navigator->get_global_position()->lon;
			item->altitude = _navigator->get_global_position()->alt;

			if (min_clearance > 0.0f && item->altitude < _navigator->get_home_position()->alt + min_clearance) {
				item->altitude = _navigator->get_home_position()->alt + min_clearance;
			}
		}

		item->altitude_is_relative = false;
		item->yaw = NAN;
		item->loiter_radius = _navigator->get_loiter_radius();
		item->acceptance_radius = _navigator->get_acceptance_radius();
		item->time_inside = 0.0f;
		item->autocontinue = false;
		item->origin = ORIGIN_ONBOARD;
	}
}

void
MissionBlock::set_follow_target_item(struct mission_item_s *item, float min_clearance, follow_target_s &target,
				     float yaw)
{
	if (_navigator->get_land_detected()->landed) {
		/* landed, don't takeoff, but switch to IDLE mode */
		item->nav_cmd = NAV_CMD_IDLE;

	} else {

		item->nav_cmd = NAV_CMD_DO_FOLLOW_REPOSITION;

		/* use current target position */
		item->lat = target.lat;
		item->lon = target.lon;
		item->altitude = _navigator->get_home_position()->alt;

		if (min_clearance > 8.0f) {
			item->altitude += min_clearance;

		} else {
			item->altitude += 8.0f; // if min clearance is bad set it to 8.0 meters (well above the average height of a person)
		}
	}

	item->altitude_is_relative = false;
	item->yaw = yaw;
	item->loiter_radius = _navigator->get_loiter_radius();
	item->acceptance_radius = _navigator->get_acceptance_radius();
	item->time_inside = 0.0f;
	item->autocontinue = false;
	item->origin = ORIGIN_ONBOARD;
}

void
MissionBlock::set_takeoff_item(struct mission_item_s *item, float abs_altitude, float min_pitch)
{
	item->nav_cmd = NAV_CMD_TAKEOFF;

	/* use current position */
	item->lat = _navigator->get_global_position()->lat;
	item->lon = _navigator->get_global_position()->lon;
	item->yaw = _navigator->get_global_position()->yaw;

	item->altitude = abs_altitude;
	item->altitude_is_relative = false;

	item->loiter_radius = _navigator->get_loiter_radius();
	item->pitch_min = min_pitch;
	item->autocontinue = false;
	item->origin = ORIGIN_ONBOARD;
}

void
MissionBlock::set_land_item(struct mission_item_s *item, bool at_current_location)
{

	/* VTOL transition to RW before landing */
	if (_navigator->get_vstatus()->is_vtol &&
	    !_navigator->get_vstatus()->is_rotary_wing &&
	    _param_force_vtol.get() == 1) {

		struct vehicle_command_s cmd = {};
		cmd.command = NAV_CMD_DO_VTOL_TRANSITION;
		cmd.param1 = vtol_vehicle_status_s::VEHICLE_VTOL_STATE_MC;

		_navigator->publish_vehicle_cmd(cmd);
	}

	/* set the land item */
	item->nav_cmd = NAV_CMD_LAND;

	/* use current position */
	if (at_current_location) {
		item->lat = NAN; //descend at current position
		item->lon = NAN; //descend at current position
		item->yaw = _navigator->get_local_position()->yaw;

	} else {
		/* use home position */
		item->lat = _navigator->get_home_position()->lat;
		item->lon = _navigator->get_home_position()->lon;
		item->yaw = _navigator->get_home_position()->yaw;
	}

	item->altitude = 0;
	item->altitude_is_relative = false;
	item->loiter_radius = _navigator->get_loiter_radius();
	item->acceptance_radius = _navigator->get_acceptance_radius();
	item->time_inside = 0.0f;
	item->autocontinue = true;
	item->origin = ORIGIN_ONBOARD;
}

void
MissionBlock::set_current_position_item(struct mission_item_s *item)
{
	item->nav_cmd = NAV_CMD_WAYPOINT;
	item->lat = _navigator->get_global_position()->lat;
	item->lon = _navigator->get_global_position()->lon;
	item->altitude_is_relative = false;
	item->altitude = _navigator->get_global_position()->alt;
	item->yaw = NAN;
	item->loiter_radius = _navigator->get_loiter_radius();
	item->acceptance_radius = _navigator->get_acceptance_radius();
	item->time_inside = 0.0f;
	item->autocontinue = true;
	item->origin = ORIGIN_ONBOARD;
}

void
MissionBlock::set_idle_item(struct mission_item_s *item)
{
	item->nav_cmd = NAV_CMD_IDLE;
	item->lat = _navigator->get_home_position()->lat;
	item->lon = _navigator->get_home_position()->lon;
	item->altitude_is_relative = false;
	item->altitude = _navigator->get_home_position()->alt;
	item->yaw = NAN;
	item->loiter_radius = _navigator->get_loiter_radius();
	item->acceptance_radius = _navigator->get_acceptance_radius();
	item->time_inside = 0.0f;
	item->autocontinue = true;
	item->origin = ORIGIN_ONBOARD;
}