PX4-Autopilot/src/modules/gimbal/input_rc.cpp

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#include "input_rc.h"

#include <math.h>
#include <errno.h>
#include <mathlib/mathlib.h>
#include <matrix/matrix/math.hpp>
#include <px4_platform_common/posix.h>
#include <px4_platform_common/defines.h>


namespace gimbal
{

InputRC::InputRC(Parameters &parameters) :
	InputBase(parameters)
{}

InputRC::~InputRC()
{
	if (_manual_control_setpoint_sub >= 0) {
		orb_unsubscribe(_manual_control_setpoint_sub);
	}
}

int InputRC::initialize()
{
	_manual_control_setpoint_sub = orb_subscribe(ORB_ID(manual_control_setpoint));

	if (_manual_control_setpoint_sub < 0) {
		return -errno;
	}

	return 0;
}

InputRC::UpdateResult InputRC::update(unsigned int timeout_ms, ControlData &control_data, bool already_active)
{
	px4_pollfd_struct_t polls[1];
	polls[0].fd = 		_manual_control_setpoint_sub;
	polls[0].events = 	POLLIN;

	int ret = px4_poll(polls, 1, timeout_ms);

	if (ret < 0) {
		return UpdateResult::NoUpdate;
	}

	if (ret == 0) {
		// If we have been active before, we stay active, unless someone steals
		// the control away.
		if (already_active) {
			return UpdateResult::UpdatedActive;
		}
	}

	if (polls[0].revents & POLLIN) {
		return _read_control_data_from_subscription(control_data, already_active);
	}

	return UpdateResult::NoUpdate;
}

InputRC::UpdateResult InputRC::_read_control_data_from_subscription(ControlData &control_data, bool already_active)
{
	manual_control_setpoint_s manual_control_setpoint{};
	orb_copy(ORB_ID(manual_control_setpoint), _manual_control_setpoint_sub, &manual_control_setpoint);
	control_data.type = ControlData::Type::Angle;

	float new_aux_values[3];

	for (int i = 0; i < 3; ++i) {
		new_aux_values[i] = _get_aux_value(manual_control_setpoint, i);
	}

	// If we were already active previously, we just update normally. Otherwise, there needs to be
	// a major stick movement to re-activate manual (or it's running for the very first time).

	// Detect a big stick movement
	const bool major_movement = [&]() {
		for (int i = 0; i < 3; ++i) {
			if (fabsf(_last_set_aux_values[i] - new_aux_values[i]) > 0.25f) {
				return true;
			}
		}

		return false;
	}();

	if (already_active || major_movement) {
		control_data.sysid_primary_control = _parameters.mav_sysid;
		control_data.compid_primary_control = _parameters.mav_compid;

		if (_parameters.mnt_rc_in_mode == 0) {
			// We scale manual input from roll -180..180, pitch -90..90, yaw, -180..180 degrees.
			matrix::Eulerf euler(new_aux_values[0] * math::radians(180.f),
					     new_aux_values[1] * math::radians(90.f),
					     new_aux_values[2] * math::radians(180.f));

			matrix::Quatf q(euler);
			q.copyTo(control_data.type_data.angle.q);

			control_data.type_data.angle.frames[0] = ControlData::TypeData::TypeAngle::Frame::AngleAbsoluteFrame;
			control_data.type_data.angle.frames[1] = ControlData::TypeData::TypeAngle::Frame::AngleAbsoluteFrame;
			control_data.type_data.angle.frames[2] = ControlData::TypeData::TypeAngle::Frame::AngleBodyFrame;

			control_data.type_data.angle.angular_velocity[0] = NAN;
			control_data.type_data.angle.angular_velocity[1] = NAN;
			control_data.type_data.angle.angular_velocity[2] = NAN;

		} else {
			control_data.type_data.angle.q[0] = NAN;
			control_data.type_data.angle.q[1] = NAN;
			control_data.type_data.angle.q[2] = NAN;
			control_data.type_data.angle.q[3] = NAN;

			control_data.type_data.angle.angular_velocity[0] = 0.f;
			control_data.type_data.angle.angular_velocity[1] = math::radians(_parameters.mnt_rate_pitch) * new_aux_values[1];
			control_data.type_data.angle.angular_velocity[2] = math::radians(_parameters.mnt_rate_yaw) * new_aux_values[2];

			control_data.type_data.angle.frames[0] = ControlData::TypeData::TypeAngle::Frame::AngularRate;
			control_data.type_data.angle.frames[1] = ControlData::TypeData::TypeAngle::Frame::AngularRate;
			control_data.type_data.angle.frames[2] = ControlData::TypeData::TypeAngle::Frame::AngularRate;
		}

		for (int i = 0; i < 3; ++i) {
			// We always use follow mode with RC input for now.
			_last_set_aux_values[i] = new_aux_values[i];
		}

		control_data.gimbal_shutter_retract = false;

		return UpdateResult::UpdatedActive;

	} else {
		return UpdateResult::NoUpdate;
	}
}

float InputRC::_get_aux_value(const manual_control_setpoint_s &manual_control_setpoint, int channel_idx)
{
	int32_t aux_channel = [&]() {
		switch (channel_idx) {
		case 0:
			return _parameters.mnt_man_roll;

		case 1:
			return _parameters.mnt_man_pitch;

		case 2:
			return _parameters.mnt_man_yaw;

		default:
			return int32_t(0);
		}
	}();

	switch (aux_channel) {

	case 1:
		return manual_control_setpoint.aux1;

	case 2:
		return manual_control_setpoint.aux2;

	case 3:
		return manual_control_setpoint.aux3;

	case 4:
		return manual_control_setpoint.aux4;

	case 5:
		return manual_control_setpoint.aux5;

	case 6:
		return manual_control_setpoint.aux6;

	default:
		return 0.0f;
	}
}

void InputRC::print_status() const
{
	PX4_INFO("Input: RC (channels: roll=%" PRIi32 ", pitch=%" PRIi32 ", yaw=%" PRIi32 ")", _parameters.mnt_man_roll,
		 _parameters.mnt_man_pitch, _parameters.mnt_man_yaw);
}

} /* namespace gimbal */