PX4-Autopilot/src/modules/rover_differential/RoverDifferential.cpp

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#include "RoverDifferential.hpp"

using namespace time_literals;

RoverDifferential::RoverDifferential() :
	ModuleParams(nullptr),
	ScheduledWorkItem(MODULE_NAME, px4::wq_configurations::rate_ctrl)
{
	updateParams();
}

bool RoverDifferential::init()
{
	ScheduleOnInterval(10_ms); // 100 Hz
	return true;
}

void RoverDifferential::updateParams()
{
	ModuleParams::updateParams();
}

void RoverDifferential::Run()
{
	if (_parameter_update_sub.updated()) {
		parameter_update_s param_update{};
		_parameter_update_sub.copy(&param_update);
		updateParams();
		runSanityChecks();
	}

	if (_vehicle_control_mode_sub.updated()) {
		vehicle_control_mode_s vehicle_control_mode{};
		_vehicle_control_mode_sub.copy(&vehicle_control_mode);

		// Run sanity checks if the control mode changes (Note: This has to be done this way, because the topic is periodically updated at 2 Hz)
		if (_vehicle_control_mode.flag_control_position_enabled != vehicle_control_mode.flag_control_position_enabled ||
		    _vehicle_control_mode.flag_control_velocity_enabled != vehicle_control_mode.flag_control_velocity_enabled ||
		    _vehicle_control_mode.flag_control_attitude_enabled != vehicle_control_mode.flag_control_attitude_enabled ||
		    _vehicle_control_mode.flag_control_rates_enabled != vehicle_control_mode.flag_control_rates_enabled ||
		    _vehicle_control_mode.flag_control_allocation_enabled != vehicle_control_mode.flag_control_allocation_enabled) {
			_vehicle_control_mode = vehicle_control_mode;
			runSanityChecks();
			reset();

		} else {
			_vehicle_control_mode = vehicle_control_mode;
		}
	}

	if (_vehicle_control_mode.flag_armed && _sanity_checks_passed) {

		_was_armed = true;
		generateSetpoints();
		updateControllers();

	} else if (_was_armed) { // Reset all controllers and stop the vehicle
		reset();
		_differential_act_control.stopVehicle();
		_was_armed = false;
	}

}

void RoverDifferential::generateSetpoints()
{
	vehicle_status_s vehicle_status{};
	_vehicle_status_sub.copy(&vehicle_status);

	switch (vehicle_status.nav_state) {
	case vehicle_status_s::NAVIGATION_STATE_AUTO_MISSION:
	case vehicle_status_s::NAVIGATION_STATE_AUTO_LOITER:
	case vehicle_status_s::NAVIGATION_STATE_AUTO_RTL:
		_auto_mode.autoControl();
		break;

	case vehicle_status_s::NAVIGATION_STATE_OFFBOARD:
		_offboard_mode.offboardControl();
		break;

	case vehicle_status_s::NAVIGATION_STATE_MANUAL:
		_manual_mode.manual();
		break;

	case vehicle_status_s::NAVIGATION_STATE_ACRO:
		_manual_mode.acro();
		break;

	case vehicle_status_s::NAVIGATION_STATE_STAB:
		_manual_mode.stab();
		break;

	case vehicle_status_s::NAVIGATION_STATE_POSCTL:
		_manual_mode.position();
		break;

	default:
		break;
	}

}

void RoverDifferential::updateControllers()
{
	if (_vehicle_control_mode.flag_control_position_enabled) {
		_differential_pos_control.updatePosControl();
	}

	if (_vehicle_control_mode.flag_control_attitude_enabled) {
		_differential_att_control.updateAttControl();
	}

	if (_vehicle_control_mode.flag_control_rates_enabled) {
		_differential_rate_control.updateRateControl();
	}

	if (_vehicle_control_mode.flag_control_velocity_enabled) {
		_differential_speed_control.updateSpeedControl();
	}

	if (_vehicle_control_mode.flag_control_allocation_enabled) {
		_differential_act_control.updateActControl();
	}
}

void RoverDifferential::runSanityChecks()
{
	if (_vehicle_control_mode.flag_control_rates_enabled && !_differential_rate_control.runSanityChecks()) {
		_sanity_checks_passed = false;
		return;
	}

	if (_vehicle_control_mode.flag_control_attitude_enabled && !_differential_att_control.runSanityChecks()) {
		_sanity_checks_passed = false;
		return;
	}

	if (_vehicle_control_mode.flag_control_velocity_enabled && !_differential_speed_control.runSanityChecks()) {
		_sanity_checks_passed = false;
		return;
	}

	if (_vehicle_control_mode.flag_control_position_enabled && !_differential_pos_control.runSanityChecks()) {
		_sanity_checks_passed = false;
		return;
	}

	_sanity_checks_passed = true;
}

void RoverDifferential::reset()
{
	_differential_pos_control.reset();
	_differential_speed_control.reset();
	_differential_att_control.reset();
	_differential_rate_control.reset();
	_manual_mode.reset();
}

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

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

int RoverDifferential::print_usage(const char *reason)
{
	if (reason) {
		PX4_ERR("%s\n", reason);
	}

	PRINT_MODULE_DESCRIPTION(
		R"DESCR_STR(
### Description
Rover differential module.
)DESCR_STR");

	PRINT_MODULE_USAGE_NAME("rover_differential", "controller");
	PRINT_MODULE_USAGE_COMMAND("start");
	PRINT_MODULE_USAGE_DEFAULT_COMMANDS();
	return 0;
}

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