PX4-Autopilot/src/modules/control_allocator/ActuatorEffectiveness/ActuatorEffectivenessHelicopter.cpp

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#include "ActuatorEffectivenessHelicopter.hpp"
#include <lib/mathlib/mathlib.h>

using namespace matrix;

ActuatorEffectivenessHelicopter::ActuatorEffectivenessHelicopter(ModuleParams *parent)
	: ModuleParams(parent)
{
	for (int i = 0; i < NUM_SWASH_PLATE_SERVOS_MAX; ++i) {
		char buffer[17];
		snprintf(buffer, sizeof(buffer), "CA_SP0_ANG%u", i);
		_param_handles.swash_plate_servos[i].angle = param_find(buffer);
		snprintf(buffer, sizeof(buffer), "CA_SP0_ARM_L%u", i);
		_param_handles.swash_plate_servos[i].arm_length = param_find(buffer);
	}

	_param_handles.num_swash_plate_servos = param_find("CA_SP0_COUNT");

	for (int i = 0; i < NUM_CURVE_POINTS; ++i) {
		char buffer[17];
		snprintf(buffer, sizeof(buffer), "CA_HELI_THR_C%u", i);
		_param_handles.throttle_curve[i] = param_find(buffer);
		snprintf(buffer, sizeof(buffer), "CA_HELI_PITCH_C%u", i);
		_param_handles.pitch_curve[i] = param_find(buffer);
	}

	_param_handles.yaw_collective_pitch_scale = param_find("CA_HELI_YAW_CP_S");
	_param_handles.yaw_throttle_scale = param_find("CA_HELI_YAW_TH_S");

	updateParams();
}

void ActuatorEffectivenessHelicopter::updateParams()
{
	ModuleParams::updateParams();

	int32_t count = 0;

	if (param_get(_param_handles.num_swash_plate_servos, &count) != 0) {
		PX4_ERR("param_get failed");
		return;
	}

	_geometry.num_swash_plate_servos = math::constrain((int)count, 3, NUM_SWASH_PLATE_SERVOS_MAX);

	for (int i = 0; i < _geometry.num_swash_plate_servos; ++i) {
		float angle_deg{};
		param_get(_param_handles.swash_plate_servos[i].angle, &angle_deg);
		_geometry.swash_plate_servos[i].angle = math::radians(angle_deg);
		param_get(_param_handles.swash_plate_servos[i].arm_length, &_geometry.swash_plate_servos[i].arm_length);
	}

	for (int i = 0; i < NUM_CURVE_POINTS; ++i) {
		param_get(_param_handles.throttle_curve[i], &_geometry.throttle_curve[i]);
		param_get(_param_handles.pitch_curve[i], &_geometry.pitch_curve[i]);
	}

	param_get(_param_handles.yaw_collective_pitch_scale, &_geometry.yaw_collective_pitch_scale);
	param_get(_param_handles.yaw_throttle_scale, &_geometry.yaw_throttle_scale);
}

bool
ActuatorEffectivenessHelicopter::getEffectivenessMatrix(Configuration &configuration,
		EffectivenessUpdateReason external_update)
{
	if (external_update == EffectivenessUpdateReason::NO_EXTERNAL_UPDATE) {
		return false;
	}

	// As the allocation is non-linear, we use updateSetpoint() instead of the matrix
	configuration.addActuator(ActuatorType::MOTORS, Vector3f{}, Vector3f{});

	// Tail (yaw) motor
	configuration.addActuator(ActuatorType::MOTORS, Vector3f{}, Vector3f{});

	// N swash plate servos
	_first_swash_plate_servo_index = configuration.num_actuators_matrix[0];

	for (int i = 0; i < _geometry.num_swash_plate_servos; ++i) {
		configuration.addActuator(ActuatorType::SERVOS, Vector3f{}, Vector3f{});
	}

	return true;
}

void ActuatorEffectivenessHelicopter::updateSetpoint(const matrix::Vector<float, NUM_AXES> &control_sp,
		int matrix_index, ActuatorVector &actuator_sp)
{
	// throttle/collective pitch curve
	const float throttle = math::interpolateN(-control_sp(ControlAxis::THRUST_Z),
			       _geometry.throttle_curve) * throttleSpoolupProgress();
	const float collective_pitch = math::interpolateN(-control_sp(ControlAxis::THRUST_Z), _geometry.pitch_curve);

	actuator_sp(0) = throttle;
	actuator_sp(1) = control_sp(ControlAxis::YAW)
			 + fabsf(collective_pitch) * _geometry.yaw_collective_pitch_scale
			 + throttle * _geometry.yaw_throttle_scale;

	for (int i = 0; i < _geometry.num_swash_plate_servos; i++) {
		actuator_sp(_first_swash_plate_servo_index + i) = collective_pitch
				+ control_sp(ControlAxis::PITCH) * cosf(_geometry.swash_plate_servos[i].angle) *
				_geometry.swash_plate_servos[i].arm_length
				- control_sp(ControlAxis::ROLL) * sinf(_geometry.swash_plate_servos[i].angle) *
				_geometry.swash_plate_servos[i].arm_length;
	}
}