PX4-Autopilot/src/examples/fake_gyro/FakeGyro.cpp

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#include "FakeGyro.hpp"

using namespace time_literals;

FakeGyro::FakeGyro() :
	ModuleParams(nullptr),
	ScheduledWorkItem(MODULE_NAME, px4::wq_configurations::hp_default)
{
}

bool FakeGyro::init()
{
	ScheduleOnInterval(SENSOR_RATE, SENSOR_RATE);
	return true;
}

void FakeGyro::Run()
{
	if (should_exit()) {
		ScheduleClear();
		exit_and_cleanup();
		return;
	}

	sensor_gyro_fifo_s sensor_gyro_fifo{};
	sensor_gyro_fifo.timestamp_sample = hrt_absolute_time();
	sensor_gyro_fifo.device_id = 1;
	sensor_gyro_fifo.samples = GYRO_RATE / (1e6f / SENSOR_RATE);
	sensor_gyro_fifo.dt = 1e6f / GYRO_RATE; // 8 kHz fake gyro
	sensor_gyro_fifo.scale = math::radians(2000.f) / static_cast<float>(INT16_MAX - 1); // 2000 degrees/second max

	const float dt_s = sensor_gyro_fifo.dt / 1e6f;
	const float x_freq = 15.f;  // 15 Hz x frequency
	const float y_freq = 63.5f; // 63.5 Hz y frequency
	const float z_freq = 99.f;  // 99 Hz z frequency

	for (int n = 0; n < sensor_gyro_fifo.samples; n++) {
		_time += dt_s;
		const float k = 2.f * M_PI_F * _time;

		sensor_gyro_fifo.x[n] = (INT16_MAX - 1) * sinf(k * x_freq);
		sensor_gyro_fifo.y[n] = (INT16_MAX - 1) / 2 * sinf(k * y_freq);
		sensor_gyro_fifo.z[n] = (INT16_MAX - 1) * cosf(k * z_freq);
	}

	sensor_gyro_fifo.timestamp = hrt_absolute_time();
	_sensor_gyro_fifo_pub.publish(sensor_gyro_fifo);
}

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

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

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

	PRINT_MODULE_DESCRIPTION(
		R"DESCR_STR(
### Description

)DESCR_STR");

	PRINT_MODULE_USAGE_NAME("fake_gyro", "driver");
	PRINT_MODULE_USAGE_COMMAND("start");
	PRINT_MODULE_USAGE_DEFAULT_COMMANDS();
	return 0;
}

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