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
  33 // ****** convert Lat,Lon,Alt to ECEF  ************
  34 void LLA2ECEF(int32_t LLAi[3], double ECEF[3]);
  35
  36 // ****** convert ECEF to Lat,Lon,Alt (ITERATIVE!) *********
  37 uint16_t ECEF2LLA(double ECEF[3], float LLA[3]);
  38
  39 void RneFromLLA(int32_t LLAi[3], float Rne[3][3]);
  40
  41 // ****** find rotation matrix from rotation vector
  42 void Rv2Rot(float Rv[3], float R[3][3]);
  43
  44 // ****** find roll, pitch, yaw from quaternion ********
  45 void Quaternion2RPY(const float q[4], float rpy[3]);
  46
  47 // ****** find quaternion from roll, pitch, yaw ********
  48 void RPY2Quaternion(const float rpy[3], float q[4]);
  49
  50 // ** Find Rbe, that rotates a vector from earth fixed to body frame, from quaternion **
  51 void Quaternion2R(float q[4], float Rbe[3][3]);
  52
  53 // ** Find first row of Rbe, that rotates a vector from earth fixed to body frame, from quaternion **
  54 // ** This vector corresponds to the fuselage/roll vector xB **
  55 void QuaternionC2xB(const float q0, const float q1, const float q2, const float q3, float x[3]);
  56 void Quaternion2xB(const float q[4], float x[3]);
  57
  58 // ** Find second row of Rbe, that rotates a vector from earth fixed to body frame, from quaternion **
  59 // ** This vector corresponds to the spanwise/pitch vector yB **
  60 void QuaternionC2yB(const float q0, const float q1, const float q2, const float q3, float y[3]);
  61 void Quaternion2yB(const float q[4], float y[3]);
  62
  63 // ** Find third row of Rbe, that rotates a vector from earth fixed to body frame, from quaternion **
  64 // ** This vector corresponds to the vertical/yaw vector zB **
  65 void QuaternionC2zB(const float q0, const float q1, const float q2, const float q3, float z[3]);
  66 void Quaternion2zB(const float q[4], float z[3]);
  67
  68 // ****** Express LLA in a local NED Base Frame ********
  69 void LLA2Base(int32_t LLAi[3], double BaseECEF[3], float Rne[3][3], float NED[3]);
  70
  71 // ****** Express ECEF in a local NED Base Frame ********
  72 void ECEF2Base(double ECEF[3], double BaseECEF[3], float Rne[3][3], float NED[3]);
  73
  74 // ****** convert Rotation Matrix to Quaternion ********
  75 // ****** if R converts from e to b, q is rotation from e to b ****
  76 void R2Quaternion(float R[3][3], float q[4]);
  77
  78 // ****** Rotation Matrix from Two Vector Directions ********
  79 // ****** given two vector directions (v1 and v2) known in two frames (b and e) find Rbe ***
  80 // ****** solution is approximate if can't be exact ***
  81 uint8_t RotFrom2Vectors(const float v1b[3], const float v1e[3], const float v2b[3], const float v2e[3], float Rbe[3][3]);
  82
  83 // ****** Vector Cross Product ********
  84 void CrossProduct(const float v1[3], const float v2[3], float result[3]);
  85
  86 // ****** Vector Magnitude ********
  87 float VectorMagnitude(const float v[3]);
  88
  89 void quat_inverse(float q[4]);
  90 void quat_copy(const float q[4], float qnew[4]);
  91 void quat_mult(const float q1[4], const float q2[4], float qout[4]);
  92 void rot_mult(float R[3][3], const float vec[3], float vec_out[3]);
  93 /**
  94  * matrix_mult_3x3f - perform a multiplication between two 3x3 float matrices
  95  * result = a*b
  96  * @param a
  97  * @param b
  98  * @param result
  99  */
 100 static inline void matrix_mult_3x3f(float a[3][3], float b[3][3], float result[3][3])
 101 {
 102     result[0][0] = a[0][0] * b[0][0] + a[1][0] * b[0][1] + a[2][0] * b[0][2];
 103     result[0][1] = a[0][1] * b[0][0] + a[1][1] * b[0][1] + a[2][1] * b[0][2];
 104     result[0][2] = a[0][2] * b[0][0] + a[1][2] * b[0][1] + a[2][2] * b[0][2];
 105
 106     result[1][0] = a[0][0] * b[1][0] + a[1][0] * b[1][1] + a[2][0] * b[1][2];
 107     result[1][1] = a[0][1] * b[1][0] + a[1][1] * b[1][1] + a[2][1] * b[1][2];
 108     result[1][2] = a[0][2] * b[1][0] + a[1][2] * b[1][1] + a[2][2] * b[1][2];
 109
 110     result[2][0] = a[0][0] * b[2][0] + a[1][0] * b[2][1] + a[2][0] * b[2][2];
 111     result[2][1] = a[0][1] * b[2][0] + a[1][1] * b[2][1] + a[2][1] * b[2][2];
 112     result[2][2] = a[0][2] * b[2][0] + a[1][2] * b[2][1] + a[2][2] * b[2][2];
 113 }
 114
 115 static inline void matrix_inline_scale_3f(float a[3][3], float scale)
 116 {
 117     a[0][0] *= scale;
 118     a[0][1] *= scale;
 119     a[0][2] *= scale;
 120
 121     a[1][0] *= scale;
 122     a[1][1] *= scale;
 123     a[1][2] *= scale;
 124
 125     a[2][0] *= scale;
 126     a[2][1] *= scale;
 127     a[2][2] *= scale;
 128 }
 129
 130 static inline void rot_about_axis_x(const float rotation, float R[3][3])
 131 {
 132     float s = sinf(rotation);
 133     float c = cosf(rotation);
 134
 135     R[0][0] = 1;
 136     R[0][1] = 0;
 137     R[0][2] = 0;
 138
 139     R[1][0] = 0;
 140     R[1][1] = c;
 141     R[1][2] = -s;
 142
 143     R[2][0] = 0;
 144     R[2][1] = s;
 145     R[2][2] = c;
 146 }
 147
 148 static inline void rot_about_axis_y(const float rotation, float R[3][3])
 149 {
 150     float s = sinf(rotation);
 151     float c = cosf(rotation);
 152
 153     R[0][0] = c;
 154     R[0][1] = 0;
 155     R[0][2] = s;
 156
 157     R[1][0] = 0;
 158     R[1][1] = 1;
 159     R[1][2] = 0;
 160
 161     R[2][0] = -s;
 162     R[2][1] = 0;
 163     R[2][2] = c;
 164 }
 165
 166 static inline void rot_about_axis_z(const float rotation, float R[3][3])
 167 {
 168     float s = sinf(rotation);
 169     float c = cosf(rotation);
 170
 171     R[0][0] = c;
 172     R[0][1] = -s;
 173     R[0][2] = 0;
 174
 175     R[1][0] = s;
 176     R[1][1] = c;
 177     R[1][2] = 0;
 178
 179     R[2][0] = 0;
 180     R[2][1] = 0;
 181     R[2][2] = 1;
 182 }
 183
 184 #endif // COORDINATECONVERSIONS_H_