ardupilot/libraries/AC_Avoidance/AC_Avoid.h

144 lines
6.6 KiB
C++

#pragma once
#include <AP_Common/AP_Common.h>
#include <AP_Param/AP_Param.h>
#include <AP_Math/AP_Math.h>
#include <AP_AHRS/AP_AHRS.h> // AHRS library
#include <AC_AttitudeControl/AC_AttitudeControl.h> // Attitude controller library for sqrt controller
#include <AC_Fence/AC_Fence.h> // Failsafe fence library
#include <AP_Proximity/AP_Proximity.h>
#include <AP_Beacon/AP_Beacon.h>
#define AC_AVOID_ACCEL_CMSS_MAX 100.0f // maximum acceleration/deceleration in cm/s/s used to avoid hitting fence
// bit masks for enabled fence types.
#define AC_AVOID_DISABLED 0 // avoidance disabled
#define AC_AVOID_STOP_AT_FENCE 1 // stop at fence
#define AC_AVOID_USE_PROXIMITY_SENSOR 2 // stop based on proximity sensor output
#define AC_AVOID_STOP_AT_BEACON_FENCE 4 // stop based on beacon perimeter
#define AC_AVOID_DEFAULT (AC_AVOID_STOP_AT_FENCE | AC_AVOID_USE_PROXIMITY_SENSOR)
// definitions for non-GPS avoidance
#define AC_AVOID_NONGPS_DIST_MAX_DEFAULT 5.0f // objects over 5m away are ignored (default value for DIST_MAX parameter)
#define AC_AVOID_ANGLE_MAX_PERCENT 0.75f // object avoidance max lean angle as a percentage (expressed in 0 ~ 1 range) of total vehicle max lean angle
/*
* This class prevents the vehicle from leaving a polygon fence in
* 2 dimensions by limiting velocity (adjust_velocity).
*/
class AC_Avoid {
public:
AC_Avoid(const AP_AHRS& ahrs, const AC_Fence& fence, const AP_Proximity& proximity, const AP_Beacon* beacon = nullptr);
/* Do not allow copies */
AC_Avoid(const AC_Avoid &other) = delete;
AC_Avoid &operator=(const AC_Avoid&) = delete;
/*
* Adjusts the desired velocity so that the vehicle can stop
* before the fence/object.
* Note: Vector3f version is for convenience and only adjusts x and y axis
*/
void adjust_velocity(float kP, float accel_cmss, Vector2f &desired_vel_cms, float dt);
void adjust_velocity(float kP, float accel_cmss, Vector3f &desired_vel_cms, float dt);
// adjust desired horizontal speed so that the vehicle stops before the fence or object
// accel (maximum acceleration/deceleration) is in m/s/s
// heading is in radians
// speed is in m/s
// kP should be zero for linear response, non-zero for non-linear response
// dt is the time since the last call in seconds
void adjust_speed(float kP, float accel, float heading, float &speed, float dt);
// adjust vertical climb rate so vehicle does not break the vertical fence
void adjust_velocity_z(float kP, float accel_cmss, float& climb_rate_cms, float dt);
// adjust roll-pitch to push vehicle away from objects
// roll and pitch value are in centi-degrees
// angle_max is the user defined maximum lean angle for the vehicle in centi-degrees
void adjust_roll_pitch(float &roll, float &pitch, float angle_max);
// enable/disable proximity based avoidance
void proximity_avoidance_enable(bool on_off) { _proximity_enabled = on_off; }
bool proximity_avoidance_enabled() { return _proximity_enabled; }
// helper functions
// Limits the component of desired_vel_cms in the direction of the unit vector
// limit_direction to be at most the maximum speed permitted by the limit_distance_cm.
// uses velocity adjustment idea from Randy's second email on this thread:
// https://groups.google.com/forum/#!searchin/drones-discuss/obstacle/drones-discuss/QwUXz__WuqY/qo3G8iTLSJAJ
void limit_velocity(float kP, float accel_cmss, Vector2f &desired_vel_cms, const Vector2f& limit_direction, float limit_distance_cm, float dt) const;
// compute the speed such that the stopping distance of the vehicle will
// be exactly the input distance.
// kP should be non-zero for Copter which has a non-linear response
float get_max_speed(float kP, float accel_cmss, float distance_cm, float dt) const;
static const struct AP_Param::GroupInfo var_info[];
private:
// behaviour types (see BEHAVE parameter)
enum BehaviourType {
BEHAVIOR_SLIDE = 0,
BEHAVIOR_STOP = 1
};
/*
* Adjusts the desired velocity for the circular fence.
*/
void adjust_velocity_circle_fence(float kP, float accel_cmss, Vector2f &desired_vel_cms, float dt);
/*
* Adjusts the desired velocity for the polygon fence.
*/
void adjust_velocity_polygon_fence(float kP, float accel_cmss, Vector2f &desired_vel_cms, float dt);
/*
* Adjusts the desired velocity for the beacon fence.
*/
void adjust_velocity_beacon_fence(float kP, float accel_cmss, Vector2f &desired_vel_cms, float dt);
/*
* Adjusts the desired velocity based on output from the proximity sensor
*/
void adjust_velocity_proximity(float kP, float accel_cmss, Vector2f &desired_vel_cms, float dt);
/*
* Adjusts the desired velocity given an array of boundary points
* earth_frame should be true if boundary is in earth-frame, false for body-frame
* margin is the distance (in meters) that the vehicle should stop short of the polygon
*/
void adjust_velocity_polygon(float kP, float accel_cmss, Vector2f &desired_vel_cms, const Vector2f* boundary, uint16_t num_points, bool earth_frame, float margin, float dt);
/*
* Computes distance required to stop, given current speed.
*/
float get_stopping_distance(float kP, float accel_cmss, float speed_cms) const;
/*
* methods for avoidance in non-GPS flight modes
*/
// convert distance (in meters) to a lean percentage (in 0~1 range) for use in manual flight modes
float distance_to_lean_pct(float dist_m);
// returns the maximum positive and negative roll and pitch percentages (in -1 ~ +1 range) based on the proximity sensor
void get_proximity_roll_pitch_pct(float &roll_positive, float &roll_negative, float &pitch_positive, float &pitch_negative);
// external references
const AP_AHRS& _ahrs;
const AC_Fence& _fence;
const AP_Proximity& _proximity;
const AP_Beacon* _beacon;
// parameters
AP_Int8 _enabled;
AP_Int16 _angle_max; // maximum lean angle to avoid obstacles (only used in non-GPS flight modes)
AP_Float _dist_max; // distance (in meters) from object at which obstacle avoidance will begin in non-GPS modes
AP_Float _margin; // vehicle will attempt to stay this distance (in meters) from objects while in GPS modes
AP_Int8 _behavior; // avoidance behaviour (slide or stop)
bool _proximity_enabled = true; // true if proximity sensor based avoidance is enabled (used to allow pilot to enable/disable)
};