PX4-Autopilot/src/modules/rover_ackermann/AckermannActControl/AckermannActControl.cpp

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#include "AckermannActControl.hpp"

using namespace time_literals;

AckermannActControl::AckermannActControl(ModuleParams *parent) : ModuleParams(parent)
{
	updateParams();
}

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

	if (_param_ra_str_rate_limit.get() > FLT_EPSILON && _param_ra_max_str_ang.get() > FLT_EPSILON) {
		_servo_setpoint.setSlewRate((M_DEG_TO_RAD_F * _param_ra_str_rate_limit.get()) / _param_ra_max_str_ang.get());
	}

	if (_param_ro_accel_limit.get() > FLT_EPSILON && _param_ro_max_thr_speed.get() > FLT_EPSILON) {
		_motor_setpoint.setSlewRate(_param_ro_accel_limit.get() / _param_ro_max_thr_speed.get());
	}
}

void AckermannActControl::updateActControl()
{
	const hrt_abstime timestamp_prev = _timestamp;
	_timestamp = hrt_absolute_time();
	const float dt = math::constrain(_timestamp - timestamp_prev, 1_ms, 10_ms) * 1e-6f;

	// Motor control
	if (_surface_vehicle_throttle_setpoint_sub.updated()) {
		surface_vehicle_throttle_setpoint_s surface_vehicle_throttle_setpoint{};
		_surface_vehicle_throttle_setpoint_sub.copy(&surface_vehicle_throttle_setpoint);
		_throttle_setpoint = surface_vehicle_throttle_setpoint.throttle_body_x;
	}

	if (PX4_ISFINITE(_throttle_setpoint)) {
		actuator_motors_s actuator_motors_sub{};
		_actuator_motors_sub.copy(&actuator_motors_sub);
		actuator_motors_s actuator_motors{};
		actuator_motors.reversible_flags = _param_r_rev.get();
		actuator_motors.control[0] = RoverControl::throttleControl(_motor_setpoint,
					     _throttle_setpoint, actuator_motors_sub.control[0], _param_ro_accel_limit.get(),
					     _param_ro_decel_limit.get(), _param_ro_max_thr_speed.get(), dt);
		actuator_motors.timestamp = _timestamp;
		_actuator_motors_pub.publish(actuator_motors);

	}

	// Servo control
	if (_surface_vehicle_steering_setpoint_sub.updated()) {
		surface_vehicle_steering_setpoint_s surface_vehicle_steering_setpoint{};
		_surface_vehicle_steering_setpoint_sub.copy(&surface_vehicle_steering_setpoint);
		_steering_setpoint = surface_vehicle_steering_setpoint.normalized_steering_setpoint;
	}

	if (PX4_ISFINITE(_steering_setpoint)) {
		actuator_servos_s actuator_servos_sub{};
		_actuator_servos_sub.copy(&actuator_servos_sub);

		if (_param_ra_str_rate_limit.get() > FLT_EPSILON
		    && _param_ra_max_str_ang.get() > FLT_EPSILON) { // Apply slew rate if configured
			if (fabsf(_servo_setpoint.getState() - actuator_servos_sub.control[0]) > fabsf(
				    _steering_setpoint -
				    actuator_servos_sub.control[0])) {
				_servo_setpoint.setForcedValue(actuator_servos_sub.control[0]);
			}

			_servo_setpoint.update(_steering_setpoint, dt);

		} else {
			_servo_setpoint.setForcedValue(_steering_setpoint);
		}

		actuator_servos_s actuator_servos{};
		actuator_servos.control[0] = _servo_setpoint.getState();
		actuator_servos.timestamp = _timestamp;
		_actuator_servos_pub.publish(actuator_servos);
	}
}

void AckermannActControl::stopVehicle()
{
	actuator_motors_s actuator_motors{};
	actuator_motors.reversible_flags = _param_r_rev.get();
	actuator_motors.control[0] = 0.f;
	actuator_motors.timestamp = _timestamp;
	_actuator_motors_pub.publish(actuator_motors);
	actuator_servos_s actuator_servos{};
	actuator_servos.control[0] = 0.f;
	actuator_servos.timestamp = _timestamp;
	_actuator_servos_pub.publish(actuator_servos);
}