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/**
 * @file mc_att_control.cpp
 * Multicopter attitude controller.
 *
 * @author Tobias Naegeli <naegelit@student.ethz.ch>
 * @author Lorenz Meier <lm@inf.ethz.ch>
 * @author Anton Babushkin <anton.babushkin@me.com>
 * @author Thomas Gubler <thomasgubler@gmail.com>
 * @author Julian Oes <julian@oes.ch>
 * @author Roman Bapst <bapstr@ethz.ch>
 */

#include "mc_att_control.h"

#define YAW_DEADZONE	0.05f
#define MIN_TAKEOFF_THRUST    0.2f
#define RATES_I_LIMIT	0.3f

namespace mc_att_control
{

/* oddly, ERROR is not defined for c++ */
#ifdef ERROR
# undef ERROR
#endif
static const int ERROR = -1;

}

MulticopterAttitudeControl::MulticopterAttitudeControl() :
	MulticopterAttitudeControlBase(),
	_task_should_exit(false),
	_control_task(-1),
	_actuators_0_circuit_breaker_enabled(false),

	/* publications */
	_att_sp_pub(nullptr),
	_v_rates_sp_pub(nullptr),
	_actuators_0_pub(nullptr),
	_n(),

	/* performance counters */
	_loop_perf(perf_alloc(PC_ELAPSED, "mc_att_control"))

{
	_params_handles.roll_p			= 	PX4_PARAM_INIT("MC_ROLL_P");
	_params_handles.roll_rate_p		= 	PX4_PARAM_INIT("MC_ROLLRATE_P");
	_params_handles.roll_rate_i		= 	PX4_PARAM_INIT("MC_ROLLRATE_I");
	_params_handles.roll_rate_d		= 	PX4_PARAM_INIT("MC_ROLLRATE_D");
	_params_handles.pitch_p			= 	PX4_PARAM_INIT("MC_PITCH_P");
	_params_handles.pitch_rate_p		= 	PX4_PARAM_INIT("MC_PITCHRATE_P");
	_params_handles.pitch_rate_i		= 	PX4_PARAM_INIT("MC_PITCHRATE_I");
	_params_handles.pitch_rate_d		= 	PX4_PARAM_INIT("MC_PITCHRATE_D");
	_params_handles.yaw_p			=	PX4_PARAM_INIT("MC_YAW_P");
	_params_handles.yaw_rate_p		= 	PX4_PARAM_INIT("MC_YAWRATE_P");
	_params_handles.yaw_rate_i		= 	PX4_PARAM_INIT("MC_YAWRATE_I");
	_params_handles.yaw_rate_d		= 	PX4_PARAM_INIT("MC_YAWRATE_D");
	_params_handles.yaw_ff			= 	PX4_PARAM_INIT("MC_YAW_FF");
	_params_handles.yaw_rate_max		= 	PX4_PARAM_INIT("MC_YAWRATE_MAX");
	_params_handles.man_roll_max		= 	PX4_PARAM_INIT("MC_MAN_R_MAX");
	_params_handles.man_pitch_max		= 	PX4_PARAM_INIT("MC_MAN_P_MAX");
	_params_handles.man_yaw_max		= 	PX4_PARAM_INIT("MC_MAN_Y_MAX");
	_params_handles.acro_roll_max		= 	PX4_PARAM_INIT("MC_ACRO_R_MAX");
	_params_handles.acro_pitch_max		= 	PX4_PARAM_INIT("MC_ACRO_P_MAX");
	_params_handles.acro_yaw_max		= 	PX4_PARAM_INIT("MC_ACRO_Y_MAX");

	/* fetch initial parameter values */
	parameters_update();

	/*
	 * do subscriptions
	 */
	PX4_SUBSCRIBE(_n, vehicle_attitude, MulticopterAttitudeControl::handle_vehicle_attitude, this, 0);
	PX4_SUBSCRIBE(_n, vehicle_attitude_setpoint, 0);
	PX4_SUBSCRIBE(_n, vehicle_rates_setpoint, 0);
	PX4_SUBSCRIBE(_n, vehicle_control_mode, 0);
	PX4_SUBSCRIBE(_n, parameter_update, 0);
	PX4_SUBSCRIBE(_n, manual_control_setpoint, 0);
	PX4_SUBSCRIBE(_n, actuator_armed, 0);

}

MulticopterAttitudeControl::~MulticopterAttitudeControl()
{
	if (_control_task != -1) {
		/* task wakes up every 100ms or so at the longest */
		_task_should_exit = true;

		/* wait for a second for the task to quit at our request */
		unsigned i = 0;

		do {
			/* wait 20ms */
			usleep(20000);

			/* if we have given up, kill it */
			if (++i > 50) {
				task_delete(_control_task);
				break;
			}
		} while (_control_task != -1);
	}

	// mc_att_control::g_control = nullptr;
}

int
MulticopterAttitudeControl::parameters_update()
{
	float v;

	/* roll gains */
	PX4_PARAM_GET(_params_handles.roll_p, &v);
	_params.att_p(0) = v;
	PX4_PARAM_GET(_params_handles.roll_rate_p, &v);
	_params.rate_p(0) = v;
	PX4_PARAM_GET(_params_handles.roll_rate_i, &v);
	_params.rate_i(0) = v;
	PX4_PARAM_GET(_params_handles.roll_rate_d, &v);
	_params.rate_d(0) = v;

	/* pitch gains */
	PX4_PARAM_GET(_params_handles.pitch_p, &v);
	_params.att_p(1) = v;
	PX4_PARAM_GET(_params_handles.pitch_rate_p, &v);
	_params.rate_p(1) = v;
	PX4_PARAM_GET(_params_handles.pitch_rate_i, &v);
	_params.rate_i(1) = v;
	PX4_PARAM_GET(_params_handles.pitch_rate_d, &v);
	_params.rate_d(1) = v;

	/* yaw gains */
	PX4_PARAM_GET(_params_handles.yaw_p, &v);
	_params.att_p(2) = v;
	PX4_PARAM_GET(_params_handles.yaw_rate_p, &v);
	_params.rate_p(2) = v;
	PX4_PARAM_GET(_params_handles.yaw_rate_i, &v);
	_params.rate_i(2) = v;
	PX4_PARAM_GET(_params_handles.yaw_rate_d, &v);
	_params.rate_d(2) = v;

	PX4_PARAM_GET(_params_handles.yaw_ff, &_params.yaw_ff);
	PX4_PARAM_GET(_params_handles.yaw_rate_max, &_params.yaw_rate_max);
	_params.yaw_rate_max = math::radians(_params.yaw_rate_max);

	/* manual control scale */
	PX4_PARAM_GET(_params_handles.man_roll_max, &_params.man_roll_max);
	PX4_PARAM_GET(_params_handles.man_pitch_max, &_params.man_pitch_max);
	PX4_PARAM_GET(_params_handles.man_yaw_max, &_params.man_yaw_max);
	_params.man_roll_max = math::radians(_params.man_roll_max);
	_params.man_pitch_max = math::radians(_params.man_pitch_max);
	_params.man_yaw_max = math::radians(_params.man_yaw_max);

	/* acro control scale */
	PX4_PARAM_GET(_params_handles.acro_roll_max, &v);
	_params.acro_rate_max(0) = math::radians(v);
	PX4_PARAM_GET(_params_handles.acro_pitch_max, &v);
	_params.acro_rate_max(1) = math::radians(v);
	PX4_PARAM_GET(_params_handles.acro_yaw_max, &v);
	_params.acro_rate_max(2) = math::radians(v);

	_actuators_0_circuit_breaker_enabled = circuit_breaker_enabled("CBRK_RATE_CTRL", CBRK_RATE_CTRL_KEY);

	return OK;
}

void  MulticopterAttitudeControl::handle_vehicle_attitude(const PX4_TOPIC_T(vehicle_attitude) &msg) {

	perf_begin(_loop_perf);

	/* run controller on attitude changes */
	static uint64_t last_run = 0;
	float dt = (hrt_absolute_time() - last_run) / 1000000.0f;
	last_run = hrt_absolute_time();

	/* guard against too small (< 2ms) and too large (> 20ms) dt's */
	if (dt < 0.002f) {
		dt = 0.002f;

	} else if (dt > 0.02f) {
		dt = 0.02f;
	}

	if (_v_control_mode.flag_control_attitude_enabled) {
		control_attitude(dt);

		/* publish the attitude setpoint if needed */
		if (_publish_att_sp) {
			_v_att_sp.timestamp = hrt_absolute_time();

			if (_att_sp_pub != nullptr) {
				_att_sp_pub->publish(_v_att_sp);

			} else {
				_att_sp_pub = PX4_ADVERTISE(_n, vehicle_attitude_setpoint);
			}
		}

		/* publish attitude rates setpoint */
		_v_rates_sp.roll = _rates_sp(0);
		_v_rates_sp.pitch = _rates_sp(1);
		_v_rates_sp.yaw = _rates_sp(2);
		_v_rates_sp.thrust = _thrust_sp;
		_v_rates_sp.timestamp = hrt_absolute_time();

		if (_v_rates_sp_pub != nullptr) {
			_v_rates_sp_pub->publish(_v_rates_sp);

		} else {
			_v_rates_sp_pub = PX4_ADVERTISE(_n, vehicle_rates_setpoint);
		}

	} else {
		/* attitude controller disabled, poll rates setpoint topic */
		if (_v_control_mode.flag_control_manual_enabled) {
			/* manual rates control - ACRO mode */
			_rates_sp = math::Vector<3>(_manual_control_sp.y, -_manual_control_sp.x,
						    _manual_control_sp.r).emult(_params.acro_rate_max);
			_thrust_sp = _manual_control_sp.z;

			/* reset yaw setpoint after ACRO */
			_reset_yaw_sp = true;

			/* publish attitude rates setpoint */
			_v_rates_sp.roll = _rates_sp(0);
			_v_rates_sp.pitch = _rates_sp(1);
			_v_rates_sp.yaw = _rates_sp(2);
			_v_rates_sp.thrust = _thrust_sp;
			_v_rates_sp.timestamp = hrt_absolute_time();

			if (_v_rates_sp_pub != nullptr) {
				_v_rates_sp_pub->publish(_v_rates_sp);

			} else {
				_v_rates_sp_pub = PX4_ADVERTISE(_n, vehicle_rates_setpoint);
			}

		} else {
			/* attitude controller disabled, poll rates setpoint topic */
			//XXX vehicle_rates_setpoint_poll();
			_rates_sp(0) = _v_rates_sp.roll;
			_rates_sp(1) = _v_rates_sp.pitch;
			_rates_sp(2) = _v_rates_sp.yaw;
			_thrust_sp = _v_rates_sp.thrust;
		}
	}

	if (_v_control_mode.flag_control_rates_enabled) {
		control_attitude_rates(dt);

		/* publish actuator controls */
		_actuators.control[0] = (isfinite(_att_control(0))) ? _att_control(0) : 0.0f;
		_actuators.control[1] = (isfinite(_att_control(1))) ? _att_control(1) : 0.0f;
		_actuators.control[2] = (isfinite(_att_control(2))) ? _att_control(2) : 0.0f;
		_actuators.control[3] = (isfinite(_thrust_sp)) ? _thrust_sp : 0.0f;
		_actuators.timestamp = hrt_absolute_time();

		if (!_actuators_0_circuit_breaker_enabled) {
			if (_actuators_0_pub != nullptr) {
				_actuators_0_pub->publish(_actuators);

			} else {
				_actuators_0_pub = PX4_ADVERTISE(_n, actuator_controls_0);
			}
		}
	}
}