#pragma once #include #include #include #include // P library #include // PID library #include // PI library (2-axis) #include // PID library (2-axis) #include // Inertial Navigation library #include "AC_AttitudeControl.h" // Attitude control library #include // motors library #include // common vehicle parameters // position controller default definitions #define POSCONTROL_ACCELERATION_MIN 50.0f // minimum horizontal acceleration in cm/s/s - used for sanity checking acceleration in leash length calculation #define POSCONTROL_ACCEL_XY 100.0f // default horizontal acceleration in cm/s/s. This is overwritten by waypoint and loiter controllers #define POSCONTROL_ACCEL_XY_MAX (GRAVITY_MSS*100) // max horizontal acceleration in cm/s/s that the position velocity controller will ask from the lower accel controller #define POSCONTROL_STOPPING_DIST_UP_MAX 300.0f // max stopping distance (in cm) vertically while climbing #define POSCONTROL_STOPPING_DIST_DOWN_MAX 200.0f // max stopping distance (in cm) vertically while descending #define POSCONTROL_SPEED 500.0f // default horizontal speed in cm/s #define POSCONTROL_SPEED_DOWN -150.0f // default descent rate in cm/s #define POSCONTROL_SPEED_UP 250.0f // default climb rate in cm/s #define POSCONTROL_ACCEL_Z 250.0f // default vertical acceleration in cm/s/s. #define POSCONTROL_LEASH_LENGTH_MIN 100.0f // minimum leash lengths in cm #define POSCONTROL_DT_50HZ 0.02f // time difference in seconds for 50hz update rate #define POSCONTROL_DT_400HZ 0.0025f // time difference in seconds for 400hz update rate #define POSCONTROL_ACTIVE_TIMEOUT_US 200000 // position controller is considered active if it has been called within the past 0.2 seconds #define POSCONTROL_VEL_ERROR_CUTOFF_FREQ 4.0f // low-pass filter on velocity error (unit: hz) #define POSCONTROL_THROTTLE_CUTOFF_FREQ 2.0f // low-pass filter on accel error (unit: hz) #define POSCONTROL_ACCEL_FILTER_HZ 2.0f // low-pass filter on acceleration (unit: hz) #define POSCONTROL_JERK_RATIO 1.0f // Defines the time it takes to reach the requested acceleration #define POSCONTROL_OVERSPEED_GAIN_Z 2.0f // gain controlling rate at which z-axis speed is brought back within SPEED_UP and SPEED_DOWN range class AC_PosControl { public: /// Constructor AC_PosControl(AP_AHRS_View& ahrs, const AP_InertialNav& inav, const AP_Motors& motors, AC_AttitudeControl& attitude_control); /// /// initialisation functions /// /// set_dt - sets time delta in seconds for all controllers (i.e. 100hz = 0.01, 400hz = 0.0025) /// updates z axis accel controller's D term filter void set_dt(float delta_sec); float get_dt() const { return _dt; } /// /// z position controller /// /// set_max_speed_z - sets maximum climb and descent rates /// speed_down can be positive or negative but will always be interpreted as a descent speed /// leash length will be recalculated void set_max_speed_z(float speed_down, float speed_up); /// get_max_speed_up - accessor for current maximum up speed in cm/s float get_max_speed_up() const { return _speed_up_cms; } /// get_max_speed_down - accessors for current maximum down speed in cm/s. Will be a negative number float get_max_speed_down() const { return _speed_down_cms; } /// get_vel_target_z - returns current vertical speed in cm/s float get_vel_target_z() const { return _vel_target.z; } /// set_max_accel_z - set the maximum vertical acceleration in cm/s/s /// leash length will be recalculated void set_max_accel_z(float accel_cmss); /// get_max_accel_z - returns current maximum vertical acceleration in cm/s/s float get_max_accel_z() const { return _accel_z_cms; } /// calc_leash_length - calculates the vertical leash lengths from maximum speed, acceleration /// called by update_z_controller if z-axis speed or accelerations are changed void calc_leash_length_z(); /// set_alt_target - set altitude target in cm above home void set_alt_target(float alt_cm) { _pos_target.z = alt_cm; } /// set_alt_target_with_slew - adjusts target towards a final altitude target /// should be called continuously (with dt set to be the expected time between calls) /// actual position target will be moved no faster than the speed_down and speed_up /// target will also be stopped if the motors hit their limits or leash length is exceeded void set_alt_target_with_slew(float alt_cm, float dt); /// set_alt_target_from_climb_rate - adjusts target up or down using a climb rate in cm/s /// should be called continuously (with dt set to be the expected time between calls) /// actual position target will be moved no faster than the speed_down and speed_up /// target will also be stopped if the motors hit their limits or leash length is exceeded /// set force_descend to true during landing to allow target to move low enough to slow the motors virtual void set_alt_target_from_climb_rate(float climb_rate_cms, float dt, bool force_descend); /// set_alt_target_from_climb_rate_ff - adjusts target up or down using a climb rate in cm/s using feed-forward /// should be called continuously (with dt set to be the expected time between calls) /// actual position target will be moved no faster than the speed_down and speed_up /// target will also be stopped if the motors hit their limits or leash length is exceeded /// set force_descend to true during landing to allow target to move low enough to slow the motors virtual void set_alt_target_from_climb_rate_ff(float climb_rate_cms, float dt, bool force_descend); /// add_takeoff_climb_rate - adjusts alt target up or down using a climb rate in cm/s /// should be called continuously (with dt set to be the expected time between calls) /// almost no checks are performed on the input void add_takeoff_climb_rate(float climb_rate_cms, float dt); /// set_alt_target_to_current_alt - set altitude target to current altitude void set_alt_target_to_current_alt() { _pos_target.z = _inav.get_altitude(); } /// shift altitude target (positive means move altitude up) void shift_alt_target(float z_cm); /// relax_alt_hold_controllers - set all desired and targets to measured void relax_alt_hold_controllers(float throttle_setting); /// get_alt_target - get desired altitude (in cm above home) from loiter or wp controller which should be fed into throttle controller float get_alt_target() const { return _pos_target.z; } /// get_alt_error - returns altitude error in cm float get_alt_error() const; /// get_vel_z_error_ratio - returns the proportion of error relative to the maximum request float get_vel_z_control_ratio() const { return constrain_float(_vel_z_control_ratio, 0.0f, 1.0f); } // returns horizontal error in cm float get_horizontal_error() const; /// set_target_to_stopping_point_z - sets altitude target to reasonable stopping altitude in cm above home void set_target_to_stopping_point_z(); /// get_stopping_point_z - calculates stopping point based on current position, velocity, vehicle acceleration void get_stopping_point_z(Vector3f& stopping_point) const; /// init_takeoff - initialises target altitude if we are taking off void init_takeoff(); // is_active - returns true if the z-axis position controller has been run very recently bool is_active_z() const; /// update_z_controller - fly to altitude in cm above home void update_z_controller(); // get_leash_down_z, get_leash_up_z - returns vertical leash lengths in cm float get_leash_down_z() const { return _leash_down_z; } float get_leash_up_z() const { return _leash_up_z; } /// freeze_ff_z - used to stop the feed forward being calculated during a known discontinuity void freeze_ff_z() { _flags.freeze_ff_z = true; } /// /// xy position controller /// /// get_lean_angle_max_cd - returns the maximum lean angle the autopilot may request float get_lean_angle_max_cd() const; /// init_xy_controller - initialise the xy controller /// sets target roll angle, pitch angle and I terms based on vehicle current lean angles /// should be called once whenever significant changes to the position target are made /// this does not update the xy target void init_xy_controller(); /// standby_xyz_reset - resets I terms and removes position error /// This function will let Loiter and Alt Hold continue to operate /// in the event that the flight controller is in control of the /// aircraft when in standby. void standby_xyz_reset(); /// set_max_accel_xy - set the maximum horizontal acceleration in cm/s/s /// leash length will be recalculated void set_max_accel_xy(float accel_cmss); float get_max_accel_xy() const { return _accel_cms; } /// set_max_speed_xy - set the maximum horizontal speed maximum in cm/s /// leash length will be recalculated void set_max_speed_xy(float speed_cms); float get_max_speed_xy() const { return _speed_cms; } /// set_limit_accel_xy - mark that accel has been limited /// this prevents integrator buildup void set_limit_accel_xy(void) { _limit.accel_xy = true; } /// calc_leash_length - calculates the horizontal leash length given a maximum speed, acceleration /// should be called whenever the speed, acceleration or position kP is modified void calc_leash_length_xy(); /// set the horizontal leash length void set_leash_length_xy(float leash) { _leash = leash; _flags.recalc_leash_xy = false; } /// get_pos_target - get target as position vector (from home in cm) const Vector3f& get_pos_target() const { return _pos_target; } /// set_pos_target in cm from home void set_pos_target(const Vector3f& position); /// set_xy_target in cm from home void set_xy_target(float x, float y); /// shift position target target in x, y axis void shift_pos_xy_target(float x_cm, float y_cm); /// get_desired_velocity - returns xy desired velocity (i.e. feed forward) in cm/s in lat and lon direction const Vector3f& get_desired_velocity() { return _vel_desired; } /// set_desired_velocity_z - sets desired velocity in cm/s in z axis void set_desired_velocity_z(float vel_z_cms) {_vel_desired.z = vel_z_cms;} // clear desired velocity feed-forward in z axis void clear_desired_velocity_ff_z() { _flags.use_desvel_ff_z = false; } // set desired acceleration in cm/s in xy axis void set_desired_accel_xy(float accel_lat_cms, float accel_lon_cms) { _accel_desired.x = accel_lat_cms; _accel_desired.y = accel_lon_cms; } /// set_desired_velocity_xy - sets desired velocity in cm/s in lat and lon directions /// when update_xy_controller is next called the position target is moved based on the desired velocity and /// the desired velocities are fed forward into the rate_to_accel step void set_desired_velocity_xy(float vel_lat_cms, float vel_lon_cms) {_vel_desired.x = vel_lat_cms; _vel_desired.y = vel_lon_cms; } /// set_desired_velocity - sets desired velocity in cm/s in all 3 axis /// when update_vel_controller_xyz is next called the position target is moved based on the desired velocity void set_desired_velocity(const Vector3f &des_vel) { _vel_desired = des_vel; } // overrides the velocity process variable for one timestep void override_vehicle_velocity_xy(const Vector2f& vel_xy) { _vehicle_horiz_vel = vel_xy; _flags.vehicle_horiz_vel_override = true; } // relax velocity controller by clearing velocity error and setting velocity target to current velocity void relax_velocity_controller_xy(); // is_active_xy - returns true if the xy position controller has been run very recently bool is_active_xy() const; /// update_xy_controller - run the horizontal position controller - should be called at 100hz or higher /// when use_desired_velocity is true the desired velocity (i.e. feed forward) is incorporated at the pos_to_rate step void update_xy_controller(); /// set_target_to_stopping_point_xy - sets horizontal target to reasonable stopping position in cm from home void set_target_to_stopping_point_xy(); /// get_stopping_point_xy - calculates stopping point based on current position, velocity, vehicle acceleration /// results placed in stopping_position vector /// set_accel_xy() should be called before this method to set vehicle acceleration /// set_leash_length() should have been called before this method void get_stopping_point_xy(Vector3f &stopping_point) const; /// get_distance_to_target - get horizontal distance to position target in cm (used for reporting) float get_distance_to_target() const; /// get_bearing_to_target - get bearing to target position in centi-degrees int32_t get_bearing_to_target() const; /// xyz velocity controller /// init_vel_controller_xyz - initialise the velocity controller - should be called once before the caller attempts to use the controller void init_vel_controller_xyz(); /// update_velocity_controller_xyz - run the velocity controller - should be called at 100hz or higher /// velocity targets should we set using set_desired_velocity_xyz() method /// callers should use get_roll() and get_pitch() methods and sent to the attitude controller /// throttle targets will be sent directly to the motors void update_vel_controller_xyz(); /// get desired roll, pitch which should be fed into stabilize controllers float get_roll() const { return _roll_target; } float get_pitch() const { return _pitch_target; } // get_leash_xy - returns horizontal leash length in cm float get_leash_xy() const { return _leash; } /// get pid controllers AC_P& get_pos_z_p() { return _p_pos_z; } AC_P& get_vel_z_p() { return _p_vel_z; } AC_PID& get_accel_z_pid() { return _pid_accel_z; } AC_P& get_pos_xy_p() { return _p_pos_xy; } AC_PID_2D& get_vel_xy_pid() { return _pid_vel_xy; } /// accessors for reporting const Vector3f& get_vel_target() const { return _vel_target; } const Vector3f& get_accel_target() const { return _accel_target; } // lean_angles_to_accel - convert roll, pitch lean angles to lat/lon frame accelerations in cm/s/s void accel_to_lean_angles(float accel_x_cmss, float accel_y_cmss, float& roll_target, float& pitch_target) const; // lean_angles_to_accel - convert roll, pitch lean angles to lat/lon frame accelerations in cm/s/s void lean_angles_to_accel(float& accel_x_cmss, float& accel_y_cmss) const; // time_since_last_xy_update - returns time in seconds since the horizontal position controller was last run float time_since_last_xy_update() const; void write_log(); // provide feedback on whether arming would be a good idea right now: bool pre_arm_checks(const char *param_prefix, char *failure_msg, const uint8_t failure_msg_len); // enable or disable high vibration compensation void set_vibe_comp(bool on_off) { _vibe_comp_enabled = on_off; } static const struct AP_Param::GroupInfo var_info[]; protected: // general purpose flags struct poscontrol_flags { uint16_t recalc_leash_z : 1; // 1 if we should recalculate the z axis leash length uint16_t recalc_leash_xy : 1; // 1 if we should recalculate the xy axis leash length uint16_t reset_desired_vel_to_pos : 1; // 1 if we should reset the rate_to_accel_xy step uint16_t reset_accel_to_lean_xy : 1; // 1 if we should reset the accel to lean angle step uint16_t reset_rate_to_accel_z : 1; // 1 if we should reset the rate_to_accel_z step uint16_t freeze_ff_z : 1; // 1 used to freeze velocity to accel feed forward for one iteration uint16_t use_desvel_ff_z : 1; // 1 to use z-axis desired velocity as feed forward into velocity step uint16_t vehicle_horiz_vel_override : 1; // 1 if we should use _vehicle_horiz_vel as our velocity process variable for one timestep } _flags; // limit flags structure struct poscontrol_limit_flags { uint8_t pos_up : 1; // 1 if we have hit the vertical position leash limit while going up uint8_t pos_down : 1; // 1 if we have hit the vertical position leash limit while going down uint8_t vel_up : 1; // 1 if we have hit the vertical velocity limit going up uint8_t vel_down : 1; // 1 if we have hit the vertical velocity limit going down uint8_t accel_xy : 1; // 1 if we have hit the horizontal accel limit } _limit; /// /// z controller private methods /// // run position control for Z axis // target altitude should be set with one of these functions // set_alt_target // set_target_to_stopping_point_z // init_takeoff void run_z_controller(); /// /// xy controller private methods /// /// move velocity target using desired acceleration void desired_accel_to_vel(float nav_dt); /// desired_vel_to_pos - move position target using desired velocities void desired_vel_to_pos(float nav_dt); /// run horizontal position controller correcting position and velocity /// converts position (_pos_target) to target velocity (_vel_target) /// desired velocity (_vel_desired) is combined into final target velocity /// converts desired velocities in lat/lon directions to accelerations in lat/lon frame /// converts desired accelerations provided in lat/lon frame to roll/pitch angles void run_xy_controller(float dt); /// calc_leash_length - calculates the horizontal leash length given a maximum speed, acceleration and position kP gain float calc_leash_length(float speed_cms, float accel_cms, float kP) const; /// Proportional controller with piecewise sqrt sections to constrain second derivative static Vector3f sqrt_controller_3D(const Vector3f& error, float p, float second_ord_lim); /// initialise and check for ekf position resets void init_ekf_xy_reset(); void check_for_ekf_xy_reset(); void init_ekf_z_reset(); void check_for_ekf_z_reset(); // references to inertial nav and ahrs libraries AP_AHRS_View & _ahrs; const AP_InertialNav& _inav; const AP_Motors& _motors; AC_AttitudeControl& _attitude_control; // parameters AP_Float _accel_xy_filt_hz; // XY acceleration filter cutoff frequency AP_Float _lean_angle_max; // Maximum autopilot commanded angle (in degrees). Set to zero for Angle Max AC_P _p_pos_z; AC_P _p_vel_z; AC_PID _pid_accel_z; AC_P _p_pos_xy; AC_PID_2D _pid_vel_xy; // internal variables float _dt; // time difference (in seconds) between calls from the main program uint64_t _last_update_xy_us; // system time (in microseconds) since last update_xy_controller call uint64_t _last_update_z_us; // system time (in microseconds) of last update_z_controller call float _speed_down_cms; // max descent rate in cm/s float _speed_up_cms; // max climb rate in cm/s float _speed_cms; // max horizontal speed in cm/s float _accel_z_cms; // max vertical acceleration in cm/s/s float _accel_last_z_cms; // max vertical acceleration in cm/s/s float _accel_cms; // max horizontal acceleration in cm/s/s float _leash; // horizontal leash length in cm. target will never be further than this distance from the vehicle float _leash_down_z; // vertical leash down in cm. target will never be further than this distance below the vehicle float _leash_up_z; // vertical leash up in cm. target will never be further than this distance above the vehicle float _vel_z_control_ratio = 2.0f; // confidence that we have control in the vertical axis // output from controller float _roll_target; // desired roll angle in centi-degrees calculated by position controller float _pitch_target; // desired roll pitch in centi-degrees calculated by position controller // position controller internal variables Vector3f _pos_target; // target location in cm from home Vector3f _pos_error; // error between desired and actual position in cm Vector3f _vel_desired; // desired velocity in cm/s Vector3f _vel_target; // velocity target in cm/s calculated by pos_to_rate step Vector3f _vel_error; // error between desired and actual acceleration in cm/s Vector3f _vel_last; // previous iterations velocity in cm/s Vector3f _accel_desired; // desired acceleration in cm/s/s (feed forward) Vector3f _accel_target; // acceleration target in cm/s/s Vector3f _accel_error; // acceleration error in cm/s/s Vector2f _vehicle_horiz_vel; // velocity to use if _flags.vehicle_horiz_vel_override is set LowPassFilterFloat _vel_error_filter; // low-pass-filter on z-axis velocity error LowPassFilterVector2f _accel_target_filter; // acceleration target filter // ekf reset handling uint32_t _ekf_xy_reset_ms; // system time of last recorded ekf xy position reset uint32_t _ekf_z_reset_ms; // system time of last recorded ekf altitude reset // high vibration handling bool _vibe_comp_enabled; // true when high vibration compensation is on };