bizhang_-obav/src/modules/flight_mode_manager/tasks/Descend/FlightTaskDescend.cpp

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/**
 * @file FlightTaskDescend.cpp
 */

#include "FlightTaskDescend.hpp"

bool FlightTaskDescend::activate(const vehicle_local_position_setpoint_s &last_setpoint)
{
	bool ret = FlightTask::activate(last_setpoint);
	// stay level to minimize horizontal drift
	_acceleration_setpoint = matrix::Vector3f(0.f, 0.f, NAN);
	// keep heading
	_yaw_setpoint = _yaw;
	return ret;
}

bool FlightTaskDescend::update()
{
	bool ret = FlightTask::update();

	if (PX4_ISFINITE(_velocity(2))) {
		// land with landspeed
		_velocity_setpoint(2) = _param_mpc_land_speed.get();
		_acceleration_setpoint(2) = NAN;

	} else {
		// descend with constant acceleration (crash landing)
		_velocity_setpoint(2) = NAN;
		_acceleration_setpoint(2) = .3f;
	}

	return ret;
}