px4-firmware/EKF/geo.h

310 lines
12 KiB
C

/****************************************************************************
*
* Copyright (C) 2012, 2014 PX4 Development Team. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name PX4 nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/**
* @file geo.h
*
* Definition of geo / math functions to perform geodesic calculations
*
* @author Thomas Gubler <thomasgubler@student.ethz.ch>
* @author Julian Oes <joes@student.ethz.ch>
* @author Lorenz Meier <lm@inf.ethz.ch>
* @author Anton Babushkin <anton.babushkin@me.com>
* Additional functions - @author Doug Weibel <douglas.weibel@colorado.edu>
*/
#ifndef GEO_H
#define GEO_H
#ifdef POSIX_SHARED
#include <stdbool.h>
#include "mathlib.h"
#define CONSTANTS_ONE_G 9.80665f /* m/s^2 */
#define CONSTANTS_AIR_DENSITY_SEA_LEVEL_15C 1.225f /* kg/m^3 */
#define CONSTANTS_AIR_GAS_CONST 287.1f /* J/(kg * K) */
#define CONSTANTS_ABSOLUTE_NULL_CELSIUS -273.15f /* °C */
#define CONSTANTS_RADIUS_OF_EARTH 6371000 /* meters (m) */
#define M_TWOPI_F 6.28318530717958647692f
#define M_PI_2_F 1.57079632679489661923f
#define M_RAD_TO_DEG 57.29577951308232087679f
#define M_DEG_TO_RAD 0.01745329251994329576f
#define OK 0
#define ERROR -1
// XXX remove
struct crosstrack_error_s {
bool past_end; // Flag indicating we are past the end of the line/arc segment
float distance; // Distance in meters to closest point on line/arc
float bearing; // Bearing in radians to closest point on line/arc
} ;
/* lat/lon are in radians */
struct map_projection_reference_s {
double lat_rad;
double lon_rad;
double sin_lat;
double cos_lat;
bool init_done;
uint64_t timestamp;
};
struct globallocal_converter_reference_s {
float alt;
bool init_done;
};
/**
* Checks if global projection was initialized
* @return true if map was initialized before, false else
*/
bool map_projection_global_initialized(void);
/**
* Checks if projection given as argument was initialized
* @return true if map was initialized before, false else
*/
bool map_projection_initialized(const struct map_projection_reference_s *ref);
/**
* Get the timestamp of the global map projection
* @return the timestamp of the map_projection
*/
uint64_t map_projection_global_timestamp(void);
/**
* Get the timestamp of the map projection given by the argument
* @return the timestamp of the map_projection
*/
uint64_t map_projection_timestamp(const struct map_projection_reference_s *ref);
/**
* Writes the reference values of the global projection to ref_lat and ref_lon
* @return 0 if map_projection_init was called before, -1 else
*/
int map_projection_global_reference(double *ref_lat_rad, double *ref_lon_rad);
/**
* Writes the reference values of the projection given by the argument to ref_lat and ref_lon
* @return 0 if map_projection_init was called before, -1 else
*/
int map_projection_reference(const struct map_projection_reference_s *ref, double *ref_lat_rad,
double *ref_lon_rad);
/**
* Initializes the map transformation given by the argument.
*
* Initializes the transformation between the geographic coordinate system and
* the azimuthal equidistant plane
* @param lat in degrees (47.1234567°, not 471234567°)
* @param lon in degrees (8.1234567°, not 81234567°)
*/
int map_projection_init_timestamped(struct map_projection_reference_s *ref,
double lat_0, double lon_0, uint64_t timestamp);
/**
* Initializes the map transformation given by the argument and sets the timestamp to now.
*
* Initializes the transformation between the geographic coordinate system and
* the azimuthal equidistant plane
* @param lat in degrees (47.1234567°, not 471234567°)
* @param lon in degrees (8.1234567°, not 81234567°)
*/
int map_projection_init(struct map_projection_reference_s *ref, double lat_0, double lon_0);
/**
* Transforms a point in the geographic coordinate system to the local
* azimuthal equidistant plane using the global projection
* @param x north
* @param y east
* @param lat in degrees (47.1234567°, not 471234567°)
* @param lon in degrees (8.1234567°, not 81234567°)
* @return 0 if map_projection_init was called before, -1 else
*/
int map_projection_global_project(double lat, double lon, float *x, float *y);
/* Transforms a point in the geographic coordinate system to the local
* azimuthal equidistant plane using the projection given by the argument
* @param x north
* @param y east
* @param lat in degrees (47.1234567°, not 471234567°)
* @param lon in degrees (8.1234567°, not 81234567°)
* @return 0 if map_projection_init was called before, -1 else
*/
int map_projection_project(const struct map_projection_reference_s *ref, double lat, double lon, float *x,
float *y);
/**
* Transforms a point in the local azimuthal equidistant plane to the
* geographic coordinate system using the global projection
*
* @param x north
* @param y east
* @param lat in degrees (47.1234567°, not 471234567°)
* @param lon in degrees (8.1234567°, not 81234567°)
* @return 0 if map_projection_init was called before, -1 else
*/
int map_projection_global_reproject(float x, float y, double *lat, double *lon);
/**
* Transforms a point in the local azimuthal equidistant plane to the
* geographic coordinate system using the projection given by the argument
*
* @param x north
* @param y east
* @param lat in degrees (47.1234567°, not 471234567°)
* @param lon in degrees (8.1234567°, not 81234567°)
* @return 0 if map_projection_init was called before, -1 else
*/
int map_projection_reproject(const struct map_projection_reference_s *ref, float x, float y, double *lat,
double *lon);
/**
* Get reference position of the global map projection
*/
int map_projection_global_getref(double *lat_0, double *lon_0);
/**
* Initialize the global mapping between global position (spherical) and local position (NED).
*/
int globallocalconverter_init(double lat_0, double lon_0, float alt_0, uint64_t timestamp);
/**
* Checks if globallocalconverter was initialized
* @return true if map was initialized before, false else
*/
bool globallocalconverter_initialized(void);
/**
* Convert from global position coordinates to local position coordinates using the global reference
*/
int globallocalconverter_tolocal(double lat, double lon, float alt, float *x, float *y, float *z);
/**
* Convert from local position coordinates to global position coordinates using the global reference
*/
int globallocalconverter_toglobal(float x, float y, float z, double *lat, double *lon, float *alt);
/**
* Get reference position of the global to local converter
*/
int globallocalconverter_getref(double *lat_0, double *lon_0, float *alt_0);
/**
* Returns the distance to the next waypoint in meters.
*
* @param lat_now current position in degrees (47.1234567°, not 471234567°)
* @param lon_now current position in degrees (8.1234567°, not 81234567°)
* @param lat_next next waypoint position in degrees (47.1234567°, not 471234567°)
* @param lon_next next waypoint position in degrees (8.1234567°, not 81234567°)
*/
float get_distance_to_next_waypoint(double lat_now, double lon_now, double lat_next, double lon_next);
/**
* Creates a new waypoint C on the line of two given waypoints (A, B) at certain distance
* from waypoint A
*
* @param lat_A waypoint A latitude in degrees (47.1234567°, not 471234567°)
* @param lon_A waypoint A longitude in degrees (8.1234567°, not 81234567°)
* @param lat_B waypoint B latitude in degrees (47.1234567°, not 471234567°)
* @param lon_B waypoint B longitude in degrees (8.1234567°, not 81234567°)
* @param dist distance of target waypoint from waypoint A in meters (can be negative)
* @param lat_target latitude of target waypoint C in degrees (47.1234567°, not 471234567°)
* @param lon_target longitude of target waypoint C in degrees (47.1234567°, not 471234567°)
*/
void create_waypoint_from_line_and_dist(double lat_A, double lon_A, double lat_B, double lon_B, float dist,
double *lat_target, double *lon_target);
/**
* Creates a waypoint from given waypoint, distance and bearing
* see http://www.movable-type.co.uk/scripts/latlong.html
*
* @param lat_start latitude of starting waypoint in degrees (47.1234567°, not 471234567°)
* @param lon_start longitude of starting waypoint in degrees (8.1234567°, not 81234567°)
* @param bearing in rad
* @param distance in meters
* @param lat_target latitude of target waypoint in degrees (47.1234567°, not 471234567°)
* @param lon_target longitude of target waypoint in degrees (47.1234567°, not 471234567°)
*/
void waypoint_from_heading_and_distance(double lat_start, double lon_start, float bearing, float dist,
double *lat_target, double *lon_target);
/**
* Returns the bearing to the next waypoint in radians.
*
* @param lat_now current position in degrees (47.1234567°, not 471234567°)
* @param lon_now current position in degrees (8.1234567°, not 81234567°)
* @param lat_next next waypoint position in degrees (47.1234567°, not 471234567°)
* @param lon_next next waypoint position in degrees (8.1234567°, not 81234567°)
*/
float get_bearing_to_next_waypoint(double lat_now, double lon_now, double lat_next, double lon_next);
void get_vector_to_next_waypoint(double lat_now, double lon_now, double lat_next, double lon_next, float *v_n,
float *v_e);
void get_vector_to_next_waypoint_fast(double lat_now, double lon_now, double lat_next, double lon_next,
float *v_n, float *v_e);
void add_vector_to_global_position(double lat_now, double lon_now, float v_n, float v_e, double *lat_res,
double *lon_res);
int get_distance_to_line(struct crosstrack_error_s *crosstrack_error, double lat_now, double lon_now,
double lat_start, double lon_start, double lat_end, double lon_end);
int get_distance_to_arc(struct crosstrack_error_s *crosstrack_error, double lat_now, double lon_now,
double lat_center, double lon_center,
float radius, float arc_start_bearing, float arc_sweep);
/*
* Calculate distance in global frame
*/
float get_distance_to_point_global_wgs84(double lat_now, double lon_now, float alt_now,
double lat_next, double lon_next, float alt_next,
float *dist_xy, float *dist_z);
/*
* Calculate distance in local frame (NED)
*/
float mavlink_wpm_distance_to_point_local(float x_now, float y_now, float z_now,
float x_next, float y_next, float z_next,
float *dist_xy, float *dist_z);
float _wrap_180(float bearing);
float _wrap_360(float bearing);
float _wrap_pi(float bearing);
float _wrap_2pi(float bearing);
float get_mag_declination(float lat, float lon);
#else
#include <lib/geo/geo.h>
#endif //POSIX_SHARED
#endif //GEO_H