FlightTaskManualPosition.cpp

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/**
 * @file FlightTaskManualPosition.cpp
 */

#include "FlightTaskManualPosition.hpp"
#include <mathlib/mathlib.h>
#include <float.h>

using namespace matrix;

FlightTaskManualPosition::FlightTaskManualPosition() : _collision_prevention(this)
{

}

bool FlightTaskManualPosition::updateInitialize()
{
    bool ret = FlightTaskManualAltitude::updateInitialize();
    // require valid position / velocity in xy
    return ret && PX4_ISFINITE(_position(0))
           && PX4_ISFINITE(_position(1))
           && PX4_ISFINITE(_velocity(0))
           && PX4_ISFINITE(_velocity(1));
}

bool FlightTaskManualPosition::activate(vehicle_local_position_setpoint_s last_setpoint)
{
    // all requirements from altitude-mode still have to hold
    bool ret = FlightTaskManualAltitude::activate(last_setpoint);

    _constraints.tilt = math::radians(_param_mpc_tiltmax_air.get());

    // set task specific constraint
    if (_constraints.speed_xy >= _param_mpc_vel_manual.get()) {
        _constraints.speed_xy = _param_mpc_vel_manual.get();
    }

    _position_setpoint(0) = _position(0);
    _position_setpoint(1) = _position(1);
    _velocity_setpoint(0) = _velocity_setpoint(1) = 0.0f;
    _velocity_scale = _constraints.speed_xy;

    // for position-controlled mode, we need a valid position and velocity state
    // in NE-direction
    return ret;
}

void FlightTaskManualPosition::_scaleSticks()
{
    /* Use same scaling as for FlightTaskManualAltitude */
    FlightTaskManualAltitude::_scaleSticks();

    /* Constrain length of stick inputs to 1 for xy*/
    Vector2f stick_xy(&_sticks_expo(0));

    float mag = math::constrain(stick_xy.length(), 0.0f, 1.0f);

    if (mag > FLT_EPSILON) {
        stick_xy = stick_xy.normalized() * mag;
    }

    // scale the stick inputs
    if (PX4_ISFINITE(_sub_vehicle_local_position.get().vxy_max)) {
        // estimator provides vehicle specific max

        // use the minimum of the estimator and user specified limit
        _velocity_scale = fminf(_constraints.speed_xy, _sub_vehicle_local_position.get().vxy_max);
        // Allow for a minimum of 0.3 m/s for repositioning
        _velocity_scale = fmaxf(_velocity_scale, 0.3f);

    } else if (stick_xy.length() > 0.5f) {
        // raise the limit at a constant rate up to the user specified value

        if (_velocity_scale < _constraints.speed_xy) {
            _velocity_scale += _deltatime * _param_mpc_acc_hor_estm.get();

        } else {
            _velocity_scale = _constraints.speed_xy;

        }
    }

    // scale velocity to its maximum limits
    Vector2f vel_sp_xy = stick_xy * _velocity_scale;

    /* Rotate setpoint into local frame. */
    _rotateIntoHeadingFrame(vel_sp_xy);

    // collision prevention
    if (_collision_prevention.is_active()) {
        _collision_prevention.modifySetpoint(vel_sp_xy, _velocity_scale, Vector2f(_position),
                             Vector2f(_velocity));
    }

    _velocity_setpoint(0) = vel_sp_xy(0);
    _velocity_setpoint(1) = vel_sp_xy(1);
}

void FlightTaskManualPosition::_updateXYlock()
{
    /* If position lock is not active, position setpoint is set to NAN.*/
    const float vel_xy_norm = Vector2f(_velocity).length();
    const bool apply_brake = Vector2f(_velocity_setpoint).length() < FLT_EPSILON;
    const bool stopped = (_param_mpc_hold_max_xy.get() < FLT_EPSILON || vel_xy_norm < _param_mpc_hold_max_xy.get());

    if (apply_brake && stopped && !PX4_ISFINITE(_position_setpoint(0))) {
        _position_setpoint(0) = _position(0);
        _position_setpoint(1) = _position(1);

    } else if (PX4_ISFINITE(_position_setpoint(0)) && apply_brake) {
        // Position is locked but check if a reset event has happened.
        // We will shift the setpoints.
        if (_sub_vehicle_local_position.get().xy_reset_counter != _reset_counter) {
            _position_setpoint(0) = _position(0);
            _position_setpoint(1) = _position(1);
            _reset_counter = _sub_vehicle_local_position.get().xy_reset_counter;
        }

    } else {
        /* don't lock*/
        _position_setpoint(0) = NAN;
        _position_setpoint(1) = NAN;
    }
}

void FlightTaskManualPosition::_updateSetpoints()
{
    FlightTaskManualAltitude::_updateSetpoints(); // needed to get yaw and setpoints in z-direction

    // check if an external yaw handler is active and if yes, let it update the yaw setpoints
    if (_weathervane_yaw_handler != nullptr && _weathervane_yaw_handler->is_active()) {
        _yaw_setpoint = NAN;
        _yawspeed_setpoint += _weathervane_yaw_handler->get_weathervane_yawrate();
    }

    _thrust_setpoint.setAll(NAN); // don't require any thrust setpoints
    _updateXYlock(); // check for position lock
}