flight/libraries/inc/CoordinateConversions.h

   1 /**
   2  ******************************************************************************
   3  *
   4  * @file       CoordinateConverions.h
   5  * @author     The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
   6  * @brief      Header for Coordinate conversions library in CoordinateConversions.c
   7  *             - all angles in deg
   8  *             - distances in meters
   9  *             - altitude above WGS-84 elipsoid
  10  *
  11  * @see        The GNU Public License (GPL) Version 3
  12  *
  13  *****************************************************************************/
  14 /*
  15  * This program is free software; you can redistribute it and/or modify
  16  * it under the terms of the GNU General Public License as published by
  17  * the Free Software Foundation; either version 3 of the License, or
  18  * (at your option) any later version.
  19  *
  20  * This program is distributed in the hope that it will be useful, but
  21  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  22  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  23  * for more details.
  24  *
  25  * You should have received a copy of the GNU General Public License along
  26  * with this program; if not, write to the Free Software Foundation, Inc.,
  27  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  28  */
  29
  30 #ifndef COORDINATECONVERSIONS_H_
  31 #define COORDINATECONVERSIONS_H_
  32 #include <math.h>
  33
  34 // ****** convert Lat,Lon,Alt to ECEF  ************
  35 void LLA2ECEF(const int32_t LLAi[3], float ECEF[3]);
  36
  37 // ****** convert ECEF to Lat,Lon,Alt *********
  38 void ECEF2LLA(const float ECEF[3], int32_t LLA[3]);
  39
  40 void RneFromLLA(const int32_t LLAi[3], float Rne[3][3]);
  41
  42 // ****** Express LLA in a local NED Base Frame and back ********
  43 void LLA2Base(const int32_t LLAi[3], const float BaseECEF[3], float Rne[3][3], float NED[3]);
  44 void Base2LLA(const float NED[3], const float BaseECEF[3], float Rne[3][3], int32_t LLAi[3]);
  45
  46 // ****** Express ECEF in a local NED Base Frame and back ********
  47 void ECEF2Base(const float ECEF[3], const float BaseECEF[3], float Rne[3][3], float NED[3]);
  48 void Base2ECEF(const float NED[3], const float BaseECEF[3], float Rne[3][3], float ECEF[3]);
  49
  50 // ****** find rotation matrix from rotation vector
  51 void Rv2Rot(float Rv[3], float R[3][3]);
  52
  53 // ****** find roll, pitch, yaw from quaternion ********
  54 void Quaternion2RPY(const float q[4], float rpy[3]);
  55
  56 // ****** find quaternion from roll, pitch, yaw ********
  57 void RPY2Quaternion(const float rpy[3], float q[4]);
  58
  59 // ** Find Rbe, that rotates a vector from earth fixed to body frame, from quaternion **
  60 void Quaternion2R(float q[4], float Rbe[3][3]);
  61
  62 // ** Find first row of Rbe, that rotates a vector from earth fixed to body frame, from quaternion **
  63 // ** This vector corresponds to the fuselage/roll vector xB **
  64 void QuaternionC2xB(const float q0, const float q1, const float q2, const float q3, float x[3]);
  65 void Quaternion2xB(const float q[4], float x[3]);
  66
  67 // ** Find second row of Rbe, that rotates a vector from earth fixed to body frame, from quaternion **
  68 // ** This vector corresponds to the spanwise/pitch vector yB **
  69 void QuaternionC2yB(const float q0, const float q1, const float q2, const float q3, float y[3]);
  70 void Quaternion2yB(const float q[4], float y[3]);
  71
  72 // ** Find third row of Rbe, that rotates a vector from earth fixed to body frame, from quaternion **
  73 // ** This vector corresponds to the vertical/yaw vector zB **
  74 void QuaternionC2zB(const float q0, const float q1, const float q2, const float q3, float z[3]);
  75 void Quaternion2zB(const float q[4], float z[3]);
  76
  77 // ****** convert Rotation Matrix to Quaternion ********
  78 // ****** if R converts from e to b, q is rotation from e to b ****
  79 void R2Quaternion(float R[3][3], float q[4]);
  80
  81 // ****** Rotation Matrix from Two Vector Directions ********
  82 // ****** given two vector directions (v1 and v2) known in two frames (b and e) find Rbe ***
  83 // ****** solution is approximate if can't be exact ***
  84 uint8_t RotFrom2Vectors(const float v1b[3], const float v1e[3], const float v2b[3], const float v2e[3], float Rbe[3][3]);
  85
  86 // ****** Vector Cross Product ********
  87 void CrossProduct(const float v1[3], const float v2[3], float result[3]);
  88
  89 // ****** Vector Magnitude ********
  90 float VectorMagnitude(const float v[3]);
  91
  92 void quat_inverse(float q[4]);
  93 void quat_copy(const float q[4], float qnew[4]);
  94 void quat_mult(const float q1[4], const float q2[4], float qout[4]);
  95 void rot_mult(float R[3][3], const float vec[3], float vec_out[3]);
  96 /**
  97  * matrix_mult_3x3f - perform a multiplication between two 3x3 float matrices
  98  * result = a*b
  99  * @param a
 100  * @param b
 101  * @param result
 102  */
 103 static inline void matrix_mult_3x3f(float a[3][3], float b[3][3], float result[3][3])
 104 {
 105     result[0][0] = a[0][0] * b[0][0] + a[1][0] * b[0][1] + a[2][0] * b[0][2];
 106     result[0][1] = a[0][1] * b[0][0] + a[1][1] * b[0][1] + a[2][1] * b[0][2];
 107     result[0][2] = a[0][2] * b[0][0] + a[1][2] * b[0][1] + a[2][2] * b[0][2];
 108
 109     result[1][0] = a[0][0] * b[1][0] + a[1][0] * b[1][1] + a[2][0] * b[1][2];
 110     result[1][1] = a[0][1] * b[1][0] + a[1][1] * b[1][1] + a[2][1] * b[1][2];
 111     result[1][2] = a[0][2] * b[1][0] + a[1][2] * b[1][1] + a[2][2] * b[1][2];
 112
 113     result[2][0] = a[0][0] * b[2][0] + a[1][0] * b[2][1] + a[2][0] * b[2][2];
 114     result[2][1] = a[0][1] * b[2][0] + a[1][1] * b[2][1] + a[2][1] * b[2][2];
 115     result[2][2] = a[0][2] * b[2][0] + a[1][2] * b[2][1] + a[2][2] * b[2][2];
 116 }
 117
 118 static inline void matrix_inline_scale_3f(float a[3][3], float scale)
 119 {
 120     a[0][0] *= scale;
 121     a[0][1] *= scale;
 122     a[0][2] *= scale;
 123
 124     a[1][0] *= scale;
 125     a[1][1] *= scale;
 126     a[1][2] *= scale;
 127
 128     a[2][0] *= scale;
 129     a[2][1] *= scale;
 130     a[2][2] *= scale;
 131 }
 132
 133 static inline void rot_about_axis_x(const float rotation, float R[3][3])
 134 {
 135     float s = sinf(rotation);
 136     float c = cosf(rotation);
 137
 138     R[0][0] = 1;
 139     R[0][1] = 0;
 140     R[0][2] = 0;
 141
 142     R[1][0] = 0;
 143     R[1][1] = c;
 144     R[1][2] = -s;
 145
 146     R[2][0] = 0;
 147     R[2][1] = s;
 148     R[2][2] = c;
 149 }
 150
 151 static inline void rot_about_axis_y(const float rotation, float R[3][3])
 152 {
 153     float s = sinf(rotation);
 154     float c = cosf(rotation);
 155
 156     R[0][0] = c;
 157     R[0][1] = 0;
 158     R[0][2] = s;
 159
 160     R[1][0] = 0;
 161     R[1][1] = 1;
 162     R[1][2] = 0;
 163
 164     R[2][0] = -s;
 165     R[2][1] = 0;
 166     R[2][2] = c;
 167 }
 168
 169 static inline void rot_about_axis_z(const float rotation, float R[3][3])
 170 {
 171     float s = sinf(rotation);
 172     float c = cosf(rotation);
 173
 174     R[0][0] = c;
 175     R[0][1] = -s;
 176     R[0][2] = 0;
 177
 178     R[1][0] = s;
 179     R[1][1] = c;
 180     R[1][2] = 0;
 181
 182     R[2][0] = 0;
 183     R[2][1] = 0;
 184     R[2][2] = 1;
 185 }
 186
 187 #endif // COORDINATECONVERSIONS_H_