PX4-Autopilot/src/modules/rc_update/rc_update.cpp

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 * modification, are permitted provided that the following conditions
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/**
 * @file rc_update.cpp
 *
 * @author Beat Kueng <beat-kueng@gmx.net>
 */

#include "rc_update.h"

using namespace time_literals;

namespace RCUpdate
{

RCUpdate::RCUpdate() :
	ModuleParams(nullptr),
	WorkItem(MODULE_NAME, px4::wq_configurations::hp_default),
	_loop_perf(perf_alloc(PC_ELAPSED, MODULE_NAME))
{
	// initialize parameter handles
	for (unsigned i = 0; i < RC_MAX_CHAN_COUNT; i++) {
		char nbuf[16];

		/* min values */
		sprintf(nbuf, "RC%d_MIN", i + 1);
		_parameter_handles.min[i] = param_find(nbuf);

		/* trim values */
		sprintf(nbuf, "RC%d_TRIM", i + 1);
		_parameter_handles.trim[i] = param_find(nbuf);

		/* max values */
		sprintf(nbuf, "RC%d_MAX", i + 1);
		_parameter_handles.max[i] = param_find(nbuf);

		/* channel reverse */
		sprintf(nbuf, "RC%d_REV", i + 1);
		_parameter_handles.rev[i] = param_find(nbuf);

		/* channel deadzone */
		sprintf(nbuf, "RC%d_DZ", i + 1);
		_parameter_handles.dz[i] = param_find(nbuf);
	}

	// RC to parameter mapping for changing parameters with RC
	for (int i = 0; i < rc_parameter_map_s::RC_PARAM_MAP_NCHAN; i++) {
		// shifted by 1 because param name starts at 1
		char name[rc_parameter_map_s::PARAM_ID_LEN];
		snprintf(name, rc_parameter_map_s::PARAM_ID_LEN, "RC_MAP_PARAM%d", i + 1);
		_parameter_handles.rc_map_param[i] = param_find(name);
	}

	rc_parameter_map_poll(true /* forced */);

	parameters_updated();
}

RCUpdate::~RCUpdate()
{
	perf_free(_loop_perf);
}

bool
RCUpdate::init()
{
	if (!_input_rc_sub.registerCallback()) {
		PX4_ERR("input_rc callback registration failed!");
		return false;
	}

	return true;
}

void
RCUpdate::parameters_updated()
{
	// rc values
	for (unsigned int i = 0; i < RC_MAX_CHAN_COUNT; i++) {

		float min = 0.0f;
		param_get(_parameter_handles.min[i], &min);
		_parameters.min[i] = min;

		float trim = 0.0f;
		param_get(_parameter_handles.trim[i], &trim);
		_parameters.trim[i] = trim;

		float max = 0.0f;
		param_get(_parameter_handles.max[i], &max);
		_parameters.max[i] = max;

		float rev = 0.0f;
		param_get(_parameter_handles.rev[i], &rev);
		_parameters.rev[i] = rev < 0.0f;

		float dz = 0.0f;
		param_get(_parameter_handles.dz[i], &dz);
		_parameters.dz[i] = dz;
	}

	for (int i = 0; i < rc_parameter_map_s::RC_PARAM_MAP_NCHAN; i++) {
		param_get(_parameter_handles.rc_map_param[i], &(_parameters.rc_map_param[i]));
	}

	update_rc_functions();
}

void
RCUpdate::update_rc_functions()
{
	/* update RC function mappings */
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_THROTTLE] = _param_rc_map_throttle.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_ROLL] = _param_rc_map_roll.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_PITCH] = _param_rc_map_pitch.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_YAW] = _param_rc_map_yaw.get() - 1;

	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_MODE] = _param_rc_map_mode_sw.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_RETURN] = _param_rc_map_return_sw.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_RATTITUDE] = _param_rc_map_ratt_sw.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_POSCTL] = _param_rc_map_posctl_sw.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_LOITER] = _param_rc_map_loiter_sw.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_ACRO] = _param_rc_map_acro_sw.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_OFFBOARD] = _param_rc_map_offb_sw.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_KILLSWITCH] = _param_rc_map_kill_sw.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_ARMSWITCH] = _param_rc_map_arm_sw.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_TRANSITION] = _param_rc_map_trans_sw.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_GEAR] = _param_rc_map_gear_sw.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_STAB] = _param_rc_map_stab_sw.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_MAN] = _param_rc_map_man_sw.get() - 1;

	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_FLAPS] = _param_rc_map_flaps.get() - 1;

	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_AUX_1] = _param_rc_map_aux1.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_AUX_2] = _param_rc_map_aux2.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_AUX_3] = _param_rc_map_aux3.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_AUX_4] = _param_rc_map_aux4.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_AUX_5] = _param_rc_map_aux5.get() - 1;
	_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_AUX_6] = _param_rc_map_aux6.get() - 1;

	for (int i = 0; i < rc_parameter_map_s::RC_PARAM_MAP_NCHAN; i++) {
		_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_PARAM_1 + i] = _parameters.rc_map_param[i] - 1;
	}
}

void
RCUpdate::rc_parameter_map_poll(bool forced)
{
	if (_rc_parameter_map_sub.updated() || forced) {
		_rc_parameter_map_sub.copy(&_rc_parameter_map);

		/* update parameter handles to which the RC channels are mapped */
		for (int i = 0; i < rc_parameter_map_s::RC_PARAM_MAP_NCHAN; i++) {
			if (_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_PARAM_1 + i] < 0 || !_rc_parameter_map.valid[i]) {
				/* This RC channel is not mapped to a RC-Parameter Channel (e.g. RC_MAP_PARAM1 == 0)
				 * or no request to map this channel to a param has been sent via mavlink
				 */
				continue;
			}

			/* Set the handle by index if the index is set, otherwise use the id */
			if (_rc_parameter_map.param_index[i] >= 0) {
				_parameter_handles.rc_param[i] = param_for_used_index((unsigned)_rc_parameter_map.param_index[i]);

			} else {
				_parameter_handles.rc_param[i] = param_find(&_rc_parameter_map.param_id[i * (rc_parameter_map_s::PARAM_ID_LEN + 1)]);
			}

		}

		PX4_DEBUG("rc to parameter map updated");

		for (int i = 0; i < rc_parameter_map_s::RC_PARAM_MAP_NCHAN; i++) {
			PX4_DEBUG("\ti %d param_id %s scale %.3f value0 %.3f, min %.3f, max %.3f",
				  i,
				  &_rc_parameter_map.param_id[i * (rc_parameter_map_s::PARAM_ID_LEN + 1)],
				  (double)_rc_parameter_map.scale[i],
				  (double)_rc_parameter_map.value0[i],
				  (double)_rc_parameter_map.value_min[i],
				  (double)_rc_parameter_map.value_max[i]
				 );
		}
	}
}

float
RCUpdate::get_rc_value(uint8_t func, float min_value, float max_value)
{
	if (_rc.function[func] >= 0) {
		float value = _rc.channels[_rc.function[func]];
		return math::constrain(value, min_value, max_value);

	} else {
		return 0.0f;
	}
}

switch_pos_t
RCUpdate::get_rc_sw3pos_position(uint8_t func, float on_th, bool on_inv, float mid_th, bool mid_inv)
{
	if (_rc.function[func] >= 0) {
		float value = 0.5f * _rc.channels[_rc.function[func]] + 0.5f;

		if (on_inv ? value < on_th : value > on_th) {
			return manual_control_setpoint_s::SWITCH_POS_ON;

		} else if (mid_inv ? value < mid_th : value > mid_th) {
			return manual_control_setpoint_s::SWITCH_POS_MIDDLE;

		} else {
			return manual_control_setpoint_s::SWITCH_POS_OFF;
		}

	} else {
		return manual_control_setpoint_s::SWITCH_POS_NONE;
	}
}

switch_pos_t
RCUpdate::get_rc_sw2pos_position(uint8_t func, float on_th, bool on_inv)
{
	if (_rc.function[func] >= 0) {
		float value = 0.5f * _rc.channels[_rc.function[func]] + 0.5f;

		if (on_inv ? value < on_th : value > on_th) {
			return manual_control_setpoint_s::SWITCH_POS_ON;

		} else {
			return manual_control_setpoint_s::SWITCH_POS_OFF;
		}

	} else {
		return manual_control_setpoint_s::SWITCH_POS_NONE;
	}
}

void
RCUpdate::set_params_from_rc()
{
	for (int i = 0; i < rc_parameter_map_s::RC_PARAM_MAP_NCHAN; i++) {
		if (_rc.function[rc_channels_s::RC_CHANNELS_FUNCTION_PARAM_1 + i] < 0 || !_rc_parameter_map.valid[i]) {
			/* This RC channel is not mapped to a RC-Parameter Channel (e.g. RC_MAP_PARAM1 == 0)
			 * or no request to map this channel to a param has been sent via mavlink
			 */
			continue;
		}

		float rc_val = get_rc_value((rc_channels_s::RC_CHANNELS_FUNCTION_PARAM_1 + i), -1.0, 1.0);

		/* Check if the value has changed,
		 * maybe we need to introduce a more aggressive limit here */
		if (rc_val > _param_rc_values[i] + FLT_EPSILON || rc_val < _param_rc_values[i] - FLT_EPSILON) {
			_param_rc_values[i] = rc_val;
			float param_val = math::constrain(
						  _rc_parameter_map.value0[i] + _rc_parameter_map.scale[i] * rc_val,
						  _rc_parameter_map.value_min[i], _rc_parameter_map.value_max[i]);

			param_set(_parameter_handles.rc_param[i], &param_val);
		}
	}
}

void
RCUpdate::Run()
{
	if (should_exit()) {
		_input_rc_sub.unregisterCallback();
		exit_and_cleanup();
		return;
	}

	perf_begin(_loop_perf);

	// check for parameter updates
	if (_parameter_update_sub.updated()) {
		// clear update
		parameter_update_s pupdate;
		_parameter_update_sub.copy(&pupdate);

		// update parameters from storage
		updateParams();
		parameters_updated();
	}

	rc_parameter_map_poll();

	/* read low-level values from FMU or IO RC inputs (PPM, Spektrum, S.Bus) */
	input_rc_s input_rc;

	if (_input_rc_sub.update(&input_rc)) {

		// warn if the channel count is changing (possibly indication of error)
		if (!input_rc.rc_lost) {
			if ((_channel_count_previous != input_rc.channel_count)
			    && (_channel_count_previous > 0)) {
				PX4_WARN("channel count changed %d -> %d", _channel_count_previous, input_rc.channel_count);
			}

			if ((_input_source_previous != input_rc.input_source)
			    && (_input_source_previous != input_rc_s::RC_INPUT_SOURCE_UNKNOWN)) {
				PX4_WARN("input source changed %d -> %d", _input_source_previous, input_rc.input_source);
			}
		}

		const bool input_source_stable = (input_rc.input_source == _input_source_previous);
		const bool channel_count_stable = (input_rc.channel_count == _channel_count_previous);

		_input_source_previous = input_rc.input_source;
		_channel_count_previous = input_rc.channel_count;

		/* detect RC signal loss */
		bool signal_lost = true;

		/* check flags and require at least four channels to consider the signal valid */
		if (input_rc.rc_lost || input_rc.rc_failsafe || input_rc.channel_count < 4) {
			/* signal is lost or no enough channels */
			signal_lost = true;


		} else if ((input_rc.input_source == input_rc_s::RC_INPUT_SOURCE_PX4FMU_PPM ||
			    input_rc.input_source == input_rc_s::RC_INPUT_SOURCE_PX4IO_PPM)
			   && input_rc.channel_count == 16) {

			// This is a specific RC lost check for RFD 868+/900 Modems on PPM.
			// The observation was that when RC is lost, 16 channels are active and the first 12 are 1000
			// and the remaining ones are 0.

			for (unsigned int i = 0; i < 16; i++) {
				if (i < 12 && input_rc.values[i] > 999 && input_rc.values[i] < 1005) {
					signal_lost = true;

				} else if (input_rc.values[i] == 0) {
					signal_lost = true;

				} else {
					signal_lost = false;
					break;
				}
			}

		} else {
			/* signal looks good */
			signal_lost = false;

			/* check failsafe */
			int8_t fs_ch = _rc.function[_param_rc_map_failsafe.get()]; // get channel mapped to throttle

			if (_param_rc_map_failsafe.get() > 0) { // if not 0, use channel number instead of rc.function mapping
				fs_ch = _param_rc_map_failsafe.get() - 1;
			}

			if (_param_rc_fails_thr.get() > 0 && fs_ch >= 0) {
				/* failsafe configured */
				if ((_param_rc_fails_thr.get() < _parameters.min[fs_ch] && input_rc.values[fs_ch] < _param_rc_fails_thr.get()) ||
				    (_param_rc_fails_thr.get() > _parameters.max[fs_ch] && input_rc.values[fs_ch] > _param_rc_fails_thr.get())) {
					/* failsafe triggered, signal is lost by receiver */
					signal_lost = true;
				}
			}
		}

		unsigned channel_limit = input_rc.channel_count;

		if (channel_limit > RC_MAX_CHAN_COUNT) {
			channel_limit = RC_MAX_CHAN_COUNT;
		}

		/* read out and scale values from raw message even if signal is invalid */
		for (unsigned int i = 0; i < channel_limit; i++) {

			/*
			 * 1) Constrain to min/max values, as later processing depends on bounds.
			 */
			input_rc.values[i] = math::constrain(input_rc.values[i], _parameters.min[i], _parameters.max[i]);

			/*
			 * 2) Scale around the mid point differently for lower and upper range.
			 *
			 * This is necessary as they don't share the same endpoints and slope.
			 *
			 * First normalize to 0..1 range with correct sign (below or above center),
			 * the total range is 2 (-1..1).
			 * If center (trim) == min, scale to 0..1, if center (trim) == max,
			 * scale to -1..0.
			 *
			 * As the min and max bounds were enforced in step 1), division by zero
			 * cannot occur, as for the case of center == min or center == max the if
			 * statement is mutually exclusive with the arithmetic NaN case.
			 *
			 * DO NOT REMOVE OR ALTER STEP 1!
			 */
			if (input_rc.values[i] > (_parameters.trim[i] + _parameters.dz[i])) {
				_rc.channels[i] = (input_rc.values[i] - _parameters.trim[i] - _parameters.dz[i]) / (float)(
							  _parameters.max[i] - _parameters.trim[i] - _parameters.dz[i]);

			} else if (input_rc.values[i] < (_parameters.trim[i] - _parameters.dz[i])) {
				_rc.channels[i] = (input_rc.values[i] - _parameters.trim[i] + _parameters.dz[i]) / (float)(
							  _parameters.trim[i] - _parameters.min[i] - _parameters.dz[i]);

			} else {
				/* in the configured dead zone, output zero */
				_rc.channels[i] = 0.0f;
			}

			if (_parameters.rev[i]) {
				_rc.channels[i] = -_rc.channels[i];
			}


			/* handle any parameter-induced blowups */
			if (!PX4_ISFINITE(_rc.channels[i])) {
				_rc.channels[i] = 0.0f;
			}
		}

		_rc.channel_count = input_rc.channel_count;
		_rc.rssi = input_rc.rssi;
		_rc.signal_lost = signal_lost;
		_rc.timestamp = input_rc.timestamp_last_signal;
		_rc.frame_drop_count = input_rc.rc_lost_frame_count;

		/* publish rc_channels topic even if signal is invalid, for debug */
		_rc_pub.publish(_rc);

		/* only publish manual control if the signal is still present and was present once */
		if (input_source_stable && channel_count_stable && !signal_lost && (input_rc.timestamp_last_signal > 0)) {

			/* initialize manual setpoint */
			manual_control_setpoint_s manual_control_setpoint{};
			/* set mode slot to unassigned */
			manual_control_setpoint.mode_slot = manual_control_setpoint_s::MODE_SLOT_NONE;
			/* set the timestamp to the last signal time */
			manual_control_setpoint.timestamp = input_rc.timestamp_last_signal;
			manual_control_setpoint.data_source = manual_control_setpoint_s::SOURCE_RC;

			/* limit controls */
			manual_control_setpoint.y = get_rc_value(rc_channels_s::RC_CHANNELS_FUNCTION_ROLL, -1.0, 1.0);
			manual_control_setpoint.x = get_rc_value(rc_channels_s::RC_CHANNELS_FUNCTION_PITCH, -1.0, 1.0);
			manual_control_setpoint.r = get_rc_value(rc_channels_s::RC_CHANNELS_FUNCTION_YAW, -1.0, 1.0);
			manual_control_setpoint.z = get_rc_value(rc_channels_s::RC_CHANNELS_FUNCTION_THROTTLE, 0.0, 1.0);
			manual_control_setpoint.flaps = get_rc_value(rc_channels_s::RC_CHANNELS_FUNCTION_FLAPS, -1.0, 1.0);
			manual_control_setpoint.aux1 = get_rc_value(rc_channels_s::RC_CHANNELS_FUNCTION_AUX_1, -1.0, 1.0);
			manual_control_setpoint.aux2 = get_rc_value(rc_channels_s::RC_CHANNELS_FUNCTION_AUX_2, -1.0, 1.0);
			manual_control_setpoint.aux3 = get_rc_value(rc_channels_s::RC_CHANNELS_FUNCTION_AUX_3, -1.0, 1.0);
			manual_control_setpoint.aux4 = get_rc_value(rc_channels_s::RC_CHANNELS_FUNCTION_AUX_4, -1.0, 1.0);
			manual_control_setpoint.aux5 = get_rc_value(rc_channels_s::RC_CHANNELS_FUNCTION_AUX_5, -1.0, 1.0);
			manual_control_setpoint.aux6 = get_rc_value(rc_channels_s::RC_CHANNELS_FUNCTION_AUX_6, -1.0, 1.0);

			if (_param_rc_map_fltmode.get() > 0) {
				/* number of valid slots */
				const int num_slots = manual_control_setpoint_s::MODE_SLOT_NUM;

				/* the half width of the range of a slot is the total range
				 * divided by the number of slots, again divided by two
				 */
				const float slot_width_half = 2.0f / num_slots / 2.0f;

				/* min is -1, max is +1, range is 2. We offset below min and max */
				const float slot_min = -1.0f - 0.05f;
				const float slot_max = 1.0f + 0.05f;

				/* the slot gets mapped by first normalizing into a 0..1 interval using min
				 * and max. Then the right slot is obtained by multiplying with the number of
				 * slots. And finally we add half a slot width to ensure that integer rounding
				 * will take us to the correct final index.
				 */
				manual_control_setpoint.mode_slot = (((((_rc.channels[_param_rc_map_fltmode.get() - 1] - slot_min) * num_slots) +
								       slot_width_half)
								      / (slot_max - slot_min)) + (1.0f / num_slots)) + 1;

				if (manual_control_setpoint.mode_slot > num_slots) {
					manual_control_setpoint.mode_slot = num_slots;
				}
			}

			/* mode switches */
			manual_control_setpoint.mode_switch = get_rc_sw3pos_position(rc_channels_s::RC_CHANNELS_FUNCTION_MODE,
							      _param_rc_auto_th.get(), _param_rc_auto_th.get() < 0.f,
							      _param_rc_assist_th.get(), _param_rc_assist_th.get() < 0.f);

			manual_control_setpoint.rattitude_switch = get_rc_sw2pos_position(rc_channels_s::RC_CHANNELS_FUNCTION_RATTITUDE,
					_param_rc_ratt_th.get(), _param_rc_ratt_th.get() < 0.f);
			manual_control_setpoint.posctl_switch = get_rc_sw2pos_position(rc_channels_s::RC_CHANNELS_FUNCTION_POSCTL,
								_param_rc_posctl_th.get(), _param_rc_posctl_th.get() < 0.f);
			manual_control_setpoint.return_switch = get_rc_sw2pos_position(rc_channels_s::RC_CHANNELS_FUNCTION_RETURN,
								_param_rc_return_th.get(), _param_rc_return_th.get() < 0.f);
			manual_control_setpoint.loiter_switch = get_rc_sw2pos_position(rc_channels_s::RC_CHANNELS_FUNCTION_LOITER,
								_param_rc_loiter_th.get(), _param_rc_loiter_th.get() < 0.f);
			manual_control_setpoint.acro_switch = get_rc_sw2pos_position(rc_channels_s::RC_CHANNELS_FUNCTION_ACRO,
							      _param_rc_acro_th.get(), _param_rc_acro_th.get() < 0.f);
			manual_control_setpoint.offboard_switch = get_rc_sw2pos_position(rc_channels_s::RC_CHANNELS_FUNCTION_OFFBOARD,
					_param_rc_offb_th.get(), _param_rc_offb_th.get() < 0.f);
			manual_control_setpoint.kill_switch = get_rc_sw2pos_position(rc_channels_s::RC_CHANNELS_FUNCTION_KILLSWITCH,
							      _param_rc_killswitch_th.get(), _param_rc_killswitch_th.get() < 0.f);
			manual_control_setpoint.arm_switch = get_rc_sw2pos_position(rc_channels_s::RC_CHANNELS_FUNCTION_ARMSWITCH,
							     _param_rc_armswitch_th.get(), _param_rc_armswitch_th.get() < 0.f);
			manual_control_setpoint.transition_switch = get_rc_sw2pos_position(rc_channels_s::RC_CHANNELS_FUNCTION_TRANSITION,
					_param_rc_trans_th.get(), _param_rc_trans_th.get() < 0.f);
			manual_control_setpoint.gear_switch = get_rc_sw2pos_position(rc_channels_s::RC_CHANNELS_FUNCTION_GEAR,
							      _param_rc_gear_th.get(), _param_rc_gear_th.get() < 0.f);
			manual_control_setpoint.stab_switch = get_rc_sw2pos_position(rc_channels_s::RC_CHANNELS_FUNCTION_STAB,
							      _param_rc_stab_th.get(), _param_rc_stab_th.get() < 0.f);
			manual_control_setpoint.man_switch = get_rc_sw2pos_position(rc_channels_s::RC_CHANNELS_FUNCTION_MAN,
							     _param_rc_man_th.get(), _param_rc_man_th.get() < 0.f);

			/* publish manual_control_setpoint topic */
			_manual_control_setpoint_pub.publish(manual_control_setpoint);

			/* copy from mapped manual_control_setpoint control to control group 3 */
			actuator_controls_s actuator_group_3{};

			actuator_group_3.timestamp = input_rc.timestamp_last_signal;

			actuator_group_3.control[0] = manual_control_setpoint.y;
			actuator_group_3.control[1] = manual_control_setpoint.x;
			actuator_group_3.control[2] = manual_control_setpoint.r;
			actuator_group_3.control[3] = manual_control_setpoint.z;
			actuator_group_3.control[4] = manual_control_setpoint.flaps;
			actuator_group_3.control[5] = manual_control_setpoint.aux1;
			actuator_group_3.control[6] = manual_control_setpoint.aux2;
			actuator_group_3.control[7] = manual_control_setpoint.aux3;

			/* publish actuator_controls_3 topic */
			_actuator_group_3_pub.publish(actuator_group_3);

			/* Update parameters from RC Channels (tuning with RC) if activated */
			if (hrt_elapsed_time(&_last_rc_to_param_map_time) > 1_s) {
				set_params_from_rc();
				_last_rc_to_param_map_time = hrt_absolute_time();
			}
		}
	}

	perf_end(_loop_perf);
}

int
RCUpdate::task_spawn(int argc, char *argv[])
{
	RCUpdate *instance = new RCUpdate();

	if (instance) {
		_object.store(instance);
		_task_id = task_id_is_work_queue;

		if (instance->init()) {
			return PX4_OK;
		}

	} else {
		PX4_ERR("alloc failed");
	}

	delete instance;
	_object.store(nullptr);
	_task_id = -1;

	return PX4_ERROR;
}

int
RCUpdate::custom_command(int argc, char *argv[])
{
	return print_usage("unknown command");
}

int
RCUpdate::print_usage(const char *reason)
{
	if (reason) {
		PX4_WARN("%s\n", reason);
	}

	PRINT_MODULE_DESCRIPTION(
		R"DESCR_STR(
### Description
The rc_update module handles RC channel mapping: read the raw input channels (`input_rc`),
then apply the calibration, map the RC channels to the configured channels & mode switches,
low-pass filter, and then publish as `rc_channels` and `manual_control_setpoint`.

### Implementation
To reduce control latency, the module is scheduled on input_rc publications.

)DESCR_STR");

	PRINT_MODULE_USAGE_NAME("rc_update", "system");
	PRINT_MODULE_USAGE_COMMAND("start");
	PRINT_MODULE_USAGE_DEFAULT_COMMANDS();

	return 0;
}

} // namespace RCUpdate

extern "C" __EXPORT int rc_update_main(int argc, char *argv[])
{
	return RCUpdate::RCUpdate::main(argc, argv);
}