FlightTaskOffboard.cpp

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/**
 * @file FlightTaskAuto.cpp
 */
#include "FlightTaskOffboard.hpp"
#include <mathlib/mathlib.h>
#include <float.h>

using namespace matrix;

bool FlightTaskOffboard::updateInitialize()
{
    bool ret = FlightTask::updateInitialize();

    _sub_triplet_setpoint.update();

    // require a valid triplet
    ret = ret && _sub_triplet_setpoint.get().current.valid;

    // 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 FlightTaskOffboard::activate(vehicle_local_position_setpoint_s last_setpoint)
{
    bool ret = FlightTask::activate(last_setpoint);
    _position_setpoint = _position;
    _velocity_setpoint.setZero();
    _position_lock.setAll(NAN);
    return ret;
}

bool FlightTaskOffboard::update()
{
    // reset setpoint for every loop
    _resetSetpoints();

    if (!_sub_triplet_setpoint.get().current.valid) {
        _setDefaultConstraints();
        _position_setpoint = _position;
        return false;
    }

    // Yaw / Yaw-speed
    if (_sub_triplet_setpoint.get().current.yaw_valid) {
        // yaw control required
        _yaw_setpoint = _sub_triplet_setpoint.get().current.yaw;

        if (_sub_triplet_setpoint.get().current.yawspeed_valid) {
            // yawspeed is used as feedforward
            _yawspeed_setpoint = _sub_triplet_setpoint.get().current.yawspeed;
        }

    } else if (_sub_triplet_setpoint.get().current.yawspeed_valid) {
        // only yawspeed required
        _yawspeed_setpoint = _sub_triplet_setpoint.get().current.yawspeed;
        // set yaw setpoint to NAN since not used
        _yaw_setpoint = NAN;

    }

    // Loiter
    if (_sub_triplet_setpoint.get().current.type == position_setpoint_s::SETPOINT_TYPE_LOITER) {
        // loiter just means that the vehicle should keep position
        if (!PX4_ISFINITE(_position_lock(0))) {
            _position_setpoint = _position_lock = _position;

        } else {
            _position_setpoint = _position_lock;
        }

        // don't have to continue
        return true;

    } else {
        _position_lock.setAll(NAN);
    }

    // Takeoff
    if (_sub_triplet_setpoint.get().current.type == position_setpoint_s::SETPOINT_TYPE_TAKEOFF) {
        // just do takeoff to default altitude
        if (!PX4_ISFINITE(_position_lock(0))) {
            _position_setpoint = _position_lock = _position;
            _position_setpoint(2) = _position_lock(2) = _position(2) - _param_mis_takeoff_alt.get();

        } else {
            _position_setpoint = _position_lock;
        }

        // don't have to continue
        return true;

    } else {
        _position_lock.setAll(NAN);
    }

    // Land
    if (_sub_triplet_setpoint.get().current.type == position_setpoint_s::SETPOINT_TYPE_LAND) {
        // land with landing speed, but keep position in xy
        if (!PX4_ISFINITE(_position_lock(0))) {
            _position_setpoint = _position_lock = _position;
            _position_setpoint(2) = _position_lock(2) = NAN;
            _velocity_setpoint(2) = _param_mpc_land_speed.get();

        } else {
            _position_setpoint = _position_lock;
            _velocity_setpoint(2) = _param_mpc_land_speed.get();
        }

        // don't have to continue
        return true;

    } else {
        _position_lock.setAll(NAN);
    }

    // IDLE
    if (_sub_triplet_setpoint.get().current.type == position_setpoint_s::SETPOINT_TYPE_IDLE) {
        _thrust_setpoint.zero();
        return true;
    }

    // Possible inputs:
    // 1. position setpoint
    // 2. position setpoint + velocity setpoint (velocity used as feedforward)
    // 3. velocity setpoint
    // 4. acceleration setpoint -> this will be mapped to normalized thrust setpoint because acceleration is not supported
    const bool position_ctrl_xy = _sub_triplet_setpoint.get().current.position_valid
                      && _sub_vehicle_local_position.get().xy_valid;
    const bool position_ctrl_z = _sub_triplet_setpoint.get().current.alt_valid
                     && _sub_vehicle_local_position.get().z_valid;
    const bool velocity_ctrl_xy = _sub_triplet_setpoint.get().current.velocity_valid
                      && _sub_vehicle_local_position.get().v_xy_valid;
    const bool velocity_ctrl_z = _sub_triplet_setpoint.get().current.velocity_valid
                     && _sub_vehicle_local_position.get().v_z_valid;
    const bool feedforward_ctrl_xy = position_ctrl_xy && velocity_ctrl_xy;
    const bool feedforward_ctrl_z = position_ctrl_z && velocity_ctrl_z;
    const bool acceleration_ctrl = _sub_triplet_setpoint.get().current.acceleration_valid;

    // if nothing is valid in xy, then exit offboard
    if (!(position_ctrl_xy || velocity_ctrl_xy || acceleration_ctrl)) {
        return false;
    }

    // if nothing is valid in z, then exit offboard
    if (!(position_ctrl_z || velocity_ctrl_z || acceleration_ctrl)) {
        return false;
    }

    // XY-direction
    if (feedforward_ctrl_xy) {
        _position_setpoint(0) = _sub_triplet_setpoint.get().current.x;
        _position_setpoint(1) = _sub_triplet_setpoint.get().current.y;
        _velocity_setpoint(0) = _sub_triplet_setpoint.get().current.vx;
        _velocity_setpoint(1) = _sub_triplet_setpoint.get().current.vy;

    } else if (position_ctrl_xy) {
        _position_setpoint(0) = _sub_triplet_setpoint.get().current.x;
        _position_setpoint(1) = _sub_triplet_setpoint.get().current.y;

    } else if (velocity_ctrl_xy) {

        if (_sub_triplet_setpoint.get().current.velocity_frame == position_setpoint_s::VELOCITY_FRAME_LOCAL_NED) {
            // in local frame: don't require any transformation
            _velocity_setpoint(0) = _sub_triplet_setpoint.get().current.vx;
            _velocity_setpoint(1) = _sub_triplet_setpoint.get().current.vy;

        } else if (_sub_triplet_setpoint.get().current.velocity_frame == position_setpoint_s::VELOCITY_FRAME_BODY_NED) {
            // in body frame: need to transorm first
            // Note, this transformation is wrong because body-xy is not neccessarily on the same plane as locale-xy
            _velocity_setpoint(0) = cosf(_yaw) * _sub_triplet_setpoint.get().current.vx - sinf(
                            _yaw) * _sub_triplet_setpoint.get().current.vy;
            _velocity_setpoint(1) = sinf(_yaw) * _sub_triplet_setpoint.get().current.vx + cosf(
                            _yaw) * _sub_triplet_setpoint.get().current.vy;

        } else {
            // no valid frame
            return false;
        }
    }

    // Z-direction
    if (feedforward_ctrl_z) {
        _position_setpoint(2) = _sub_triplet_setpoint.get().current.z;
        _velocity_setpoint(2) = _sub_triplet_setpoint.get().current.vz;

    } else if (position_ctrl_z) {
        _position_setpoint(2) = _sub_triplet_setpoint.get().current.z;

    } else if (velocity_ctrl_z) {
        _velocity_setpoint(2) = _sub_triplet_setpoint.get().current.vz;
    }

    // Acceleration
    // Note: this is not supported yet and will be mapped to normalized thrust directly.
    if (_sub_triplet_setpoint.get().current.acceleration_valid) {
        _thrust_setpoint(0) = _sub_triplet_setpoint.get().current.a_x;
        _thrust_setpoint(1) = _sub_triplet_setpoint.get().current.a_y;
        _thrust_setpoint(2) = _sub_triplet_setpoint.get().current.a_z;
    }

    // use default conditions of upwards position or velocity to take off
    _constraints.want_takeoff = _checkTakeoff();

    return true;
}