ardupilot/libraries/AC_WPNav/AC_Circle.h

164 lines
7.8 KiB
C++

#pragma once
#include <AP_Common/AP_Common.h>
#include <AP_Param/AP_Param.h>
#include <AP_Math/AP_Math.h>
#include <AP_InertialNav/AP_InertialNav.h> // Inertial Navigation library
#include <AC_AttitudeControl/AC_PosControl.h> // Position control library
// loiter maximum velocities and accelerations
#define AC_CIRCLE_RADIUS_DEFAULT 1000.0f // radius of the circle in cm that the vehicle will fly
#define AC_CIRCLE_RATE_DEFAULT 20.0f // turn rate in deg/sec. Positive to turn clockwise, negative for counter clockwise
#define AC_CIRCLE_ANGULAR_ACCEL_MIN 2.0f // angular acceleration should never be less than 2deg/sec
#define AC_CIRCLE_RADIUS_MAX 200000.0f // maximum allowed circle radius of 2km
class AC_Circle
{
public:
/// Constructor
AC_Circle(const AP_InertialNav& inav, const AP_AHRS_View& ahrs, AC_PosControl& pos_control);
/// init - initialise circle controller setting center specifically
/// set terrain_alt to true if center.z should be interpreted as an alt-above-terrain. Rate should be +ve in deg/sec for cw turn
/// caller should set the position controller's x,y and z speeds and accelerations before calling this
void init(const Vector3p& center, bool terrain_alt, float rate_deg_per_sec);
/// init - initialise circle controller setting center using stopping point and projecting out based on the copter's heading
/// caller should set the position controller's x,y and z speeds and accelerations before calling this
void init();
/// set circle center to a Location
void set_center(const Location& center);
/// set_circle_center as a vector from ekf origin
/// terrain_alt should be true if center.z is alt is above terrain
void set_center(const Vector3f& center, bool terrain_alt) { _center = center.topostype(); _terrain_alt = terrain_alt; }
/// get_circle_center in cm from home
const Vector3p& get_center() const { return _center; }
/// returns true if using terrain altitudes
bool center_is_terrain_alt() const { return _terrain_alt; }
/// get_radius - returns radius of circle in cm
float get_radius() const { return is_positive(_radius)?_radius:_radius_parm; }
/// set_radius_cm - sets circle radius in cm
void set_radius_cm(float radius_cm);
/// get_rate - returns target rate in deg/sec held in RATE parameter
float get_rate() const { return _rate; }
/// get_rate_current - returns actual calculated rate target in deg/sec, which may be less than _rate
float get_rate_current() const { return ToDeg(_angular_vel); }
/// set_rate - set circle rate in degrees per second
void set_rate(float deg_per_sec);
/// get_angle_total - return total angle in radians that vehicle has circled
float get_angle_total() const { return _angle_total; }
/// update - update circle controller
/// returns false on failure which indicates a terrain failsafe
bool update(float climb_rate_cms = 0.0f) WARN_IF_UNUSED;
/// get desired roll, pitch which should be fed into stabilize controllers
float get_roll() const { return _pos_control.get_roll_cd(); }
float get_pitch() const { return _pos_control.get_pitch_cd(); }
Vector3f get_thrust_vector() const { return _pos_control.get_thrust_vector(); }
float get_yaw() const { return _yaw; }
/// returns true if update has been run recently
/// used by vehicle code to determine if get_yaw() is valid
bool is_active() const;
// get_closest_point_on_circle - returns closest point on the circle
// circle's center should already have been set
// closest point on the circle will be placed in result
// result's altitude (i.e. z) will be set to the circle_center's altitude
// if vehicle is at the center of the circle, the edge directly behind vehicle will be returned
void get_closest_point_on_circle(Vector3f &result) const;
/// get horizontal distance to loiter target in cm
float get_distance_to_target() const { return _pos_control.get_pos_error_xy_cm(); }
/// get bearing to target in centi-degrees
int32_t get_bearing_to_target() const { return _pos_control.get_bearing_to_target_cd(); }
/// true if pilot control of radius and turn rate is enabled
bool pilot_control_enabled() const { return (_options.get() & CircleOptions::MANUAL_CONTROL) != 0; }
/// provide rangefinder altitude
void set_rangefinder_alt(bool use, bool healthy, float alt_cm) { _rangefinder_available = use; _rangefinder_healthy = healthy; _rangefinder_alt_cm = alt_cm; }
/// check for a change in the radius params
void check_param_change();
static const struct AP_Param::GroupInfo var_info[];
private:
// calc_velocities - calculate angular velocity max and acceleration based on radius and rate
// this should be called whenever the radius or rate are changed
// initialises the yaw and current position around the circle
// init_velocity should be set true if vehicle is just starting circle
void calc_velocities(bool init_velocity);
// init_start_angle - sets the starting angle around the circle and initialises the angle_total
// if use_heading is true the vehicle's heading will be used to init the angle causing minimum yaw movement
// if use_heading is false the vehicle's position from the center will be used to initialise the angle
void init_start_angle(bool use_heading);
// get expected source of terrain data
enum class TerrainSource {
TERRAIN_UNAVAILABLE,
TERRAIN_FROM_RANGEFINDER,
TERRAIN_FROM_TERRAINDATABASE,
};
AC_Circle::TerrainSource get_terrain_source() const;
// get terrain's altitude (in cm above the ekf origin) at the current position (+ve means terrain below vehicle is above ekf origin's altitude)
bool get_terrain_offset(float& offset_cm);
// flags structure
struct circle_flags {
uint8_t panorama : 1; // true if we are doing a panorama
} _flags;
// references to inertial nav and ahrs libraries
const AP_InertialNav& _inav;
const AP_AHRS_View& _ahrs;
AC_PosControl& _pos_control;
enum CircleOptions {
MANUAL_CONTROL = 1U << 0,
FACE_DIRECTION_OF_TRAVEL = 1U << 1,
INIT_AT_CENTER = 1U << 2, // true then the circle center will be the current location, false and the center will be 1 radius ahead
};
// parameters
AP_Float _radius_parm; // radius of circle in cm loaded from params
AP_Float _rate_parm; // rotation speed in deg/sec
AP_Int16 _options; // stick control enable/disable
// internal variables
Vector3p _center; // center of circle in cm from home
float _radius; // radius of circle in cm
float _rate; // rotation speed of circle in deg/sec. +ve for cw turn
float _yaw; // yaw heading (normally towards circle center)
float _angle; // current angular position around circle in radians (0=directly north of the center of the circle)
float _angle_total; // total angle traveled in radians
float _angular_vel; // angular velocity in radians/sec
float _angular_vel_max; // maximum velocity in radians/sec
float _angular_accel; // angular acceleration in radians/sec/sec
uint32_t _last_update_ms; // system time of last update
float _last_radius_param; // last value of radius param, used to update radius on param change
// terrain following variables
bool _terrain_alt; // true if _center.z is alt-above-terrain, false if alt-above-ekf-origin
bool _rangefinder_available; // true if range finder could be used
bool _rangefinder_healthy; // true if range finder is healthy
float _rangefinder_alt_cm; // latest rangefinder altitude
};