FlightTaskAuto.hpp

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/**
 * @file FlightTaskAuto.hpp
 *
 * Map from global triplet to local quadruple.
 */

#pragma once

#include "FlightTask.hpp"
#include <uORB/topics/position_setpoint_triplet.h>
#include <uORB/topics/position_setpoint.h>
#include <uORB/topics/home_position.h>
#include <uORB/topics/manual_control_setpoint.h>
#include <uORB/topics/vehicle_status.h>
#include <lib/ecl/geo/geo.h>
#include <ObstacleAvoidance.hpp>

/**
 * This enum has to agree with position_setpoint_s type definition
 * The only reason for not using the struct position_setpoint is because
 * of the size
 */
enum class WaypointType : int {
    position = position_setpoint_s::SETPOINT_TYPE_POSITION,
    velocity = position_setpoint_s::SETPOINT_TYPE_VELOCITY,
    loiter = position_setpoint_s::SETPOINT_TYPE_LOITER,
    takeoff = position_setpoint_s::SETPOINT_TYPE_TAKEOFF,
    land = position_setpoint_s::SETPOINT_TYPE_LAND,
    idle = position_setpoint_s::SETPOINT_TYPE_IDLE,
    offboard = position_setpoint_s::SETPOINT_TYPE_OFFBOARD, // only part of this structure due to legacy reason. It is not used within the Auto flighttasks
    follow_target = position_setpoint_s::SETPOINT_TYPE_FOLLOW_TARGET,
};

enum class State {
    offtrack, /**< Vehicle is more than cruise speed away from track */
    target_behind, /**< Vehicle is in front of target. */
    previous_infront, /**< Vehilce is behind previous waypoint.*/
    none /**< Vehicle is in normal tracking mode from triplet previous to triplet target */
};

class FlightTaskAuto : public FlightTask
{
public:
    FlightTaskAuto();

    virtual ~FlightTaskAuto() = default;
    bool activate(vehicle_local_position_setpoint_s last_setpoint) override;
    bool updateInitialize() override;
    bool updateFinalize() override;

    /**
     * Sets an external yaw handler which can be used to implement a different yaw control strategy.
     */
    void setYawHandler(WeatherVane *ext_yaw_handler) override {_ext_yaw_handler = ext_yaw_handler;}

protected:
    void _setDefaultConstraints() override;
    matrix::Vector2f _getTargetVelocityXY(); /**< only used for follow-me and only here because of legacy reason.*/
    void _updateInternalWaypoints(); /**< Depending on state of vehicle, the internal waypoints might differ from target (for instance if offtrack). */
    bool _compute_heading_from_2D_vector(float &heading, matrix::Vector2f v); /**< Computes and sets heading a 2D vector */

    matrix::Vector3f _prev_prev_wp{}; /**< Pre-previous waypoint (local frame). This will be used for smoothing trajectories -> not used yet. */
    matrix::Vector3f _prev_wp{}; /**< Previous waypoint  (local frame). If no previous triplet is available, the prev_wp is set to current position. */
    matrix::Vector3f _target{}; /**< Target waypoint  (local frame).*/
    matrix::Vector3f _next_wp{}; /**< The next waypoint after target (local frame). If no next setpoint is available, next is set to target. */
    float _mc_cruise_speed{0.0f}; /**< Requested cruise speed. If not valid, default cruise speed is used. */
    WaypointType _type{WaypointType::idle}; /**< Type of current target triplet. */

    uORB::SubscriptionData<home_position_s>         _sub_home_position{ORB_ID(home_position)};
    uORB::SubscriptionData<manual_control_setpoint_s>   _sub_manual_control_setpoint{ORB_ID(manual_control_setpoint)};
    uORB::SubscriptionData<vehicle_status_s>        _sub_vehicle_status{ORB_ID(vehicle_status)};

    State _current_state{State::none};
    float _target_acceptance_radius{0.0f}; /**< Acceptances radius of the target */
    int _mission_gear{landing_gear_s::GEAR_KEEP};

    float _yaw_sp_prev{NAN};
    bool _yaw_sp_aligned{false};

    ObstacleAvoidance _obstacle_avoidance; /**< class adjusting setpoints according to external avoidance module's input */

    DEFINE_PARAMETERS_CUSTOM_PARENT(FlightTask,
                    (ParamFloat<px4::params::MPC_XY_CRUISE>) _param_mpc_xy_cruise,
                    (ParamFloat<px4::params::MPC_CRUISE_90>) _param_mpc_cruise_90, // speed at corner when angle is 90 degrees move to line
                    (ParamFloat<px4::params::NAV_MC_ALT_RAD>)
                    _param_nav_mc_alt_rad, //vertical acceptance radius at which waypoints are updated
                    (ParamInt<px4::params::MPC_YAW_MODE>) _param_mpc_yaw_mode, // defines how heading is executed,
                    (ParamInt<px4::params::COM_OBS_AVOID>) _param_com_obs_avoid, // obstacle avoidance active
                    (ParamFloat<px4::params::MPC_YAWRAUTO_MAX>) _param_mpc_yawrauto_max,
                    (ParamFloat<px4::params::MIS_YAW_ERR>) _param_mis_yaw_err, // yaw-error threshold
                    (ParamBool<px4::params::WV_EN>) _param_wv_en // enable/disable weather vane (VTOL)
                       );

private:
    matrix::Vector2f _lock_position_xy{NAN, NAN}; /**< if no valid triplet is received, lock positition to current position */
    bool _yaw_lock{false}; /**< if within acceptance radius, lock yaw to current yaw */

    uORB::SubscriptionData<position_setpoint_triplet_s> _sub_triplet_setpoint{ORB_ID(position_setpoint_triplet)};

    matrix::Vector3f
    _triplet_target; /**< current triplet from navigator which may differ from the intenal one (_target) depending on the vehicle state. */
    matrix::Vector3f
    _triplet_prev_wp; /**< previous triplet from navigator which may differ from the intenal one (_prev_wp) depending on the vehicle state.*/
    matrix::Vector3f
    _triplet_next_wp; /**< next triplet from navigator which may differ from the intenal one (_next_wp) depending on the vehicle state.*/
    matrix::Vector2f _closest_pt; /**< closest point to the vehicle position on the line previous - target */

    map_projection_reference_s _reference_position{}; /**< Structure used to project lat/lon setpoint into local frame. */
    float _reference_altitude{NAN};  /**< Altitude relative to ground. */
    hrt_abstime _time_stamp_reference{0}; /**< time stamp when last reference update occured. */

    WeatherVane *_ext_yaw_handler{nullptr}; /**< external weathervane library, used to implement a yaw control law that turns the vehicle nose into the wind */


    void _limitYawRate(); /**< Limits the rate of change of the yaw setpoint. */
    bool _evaluateTriplets(); /**< Checks and sets triplets. */
    bool _isFinite(const position_setpoint_s &sp); /**< Checks if all waypoint triplets are finite. */
    bool _evaluateGlobalReference(); /**< Check is global reference is available. */
    State _getCurrentState(); /**< Computes the current vehicle state based on the vehicle position and navigator triplets. */
    void _set_heading_from_mode(); /**< @see  MPC_YAW_MODE */
};