maedalab / Mbed 2 deprecated MPU9250_AHRS

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Dependencies:   MPU9250_SPI mbed

main.cpp@12:5638ddcd8477, 2016-06-17 (annotated)

Committer:
mfurukawa
Date:
Fri Jun 17 15:09:49 2016 +0000
Revision:
12:5638ddcd8477
Parent:
11:3f0b35a0855c
Child:
13:3487e01bd5db
stable CH2 angle output 912kbps;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mfurukawa 3:07aa20aa678d 1 /**
mfurukawa 3:07aa20aa678d 2 * Masahiro FURUKAWA - m.furukawa@ist.osaka-u.ac.jp
mfurukawa 8:03f9b5289083 3 *
mfurukawa 6:ea0804dc7cae 4 * June 17, 2016
mfurukawa 3:07aa20aa678d 5 *
mfurukawa 6:ea0804dc7cae 6 * MPU9250 9DoF Sensor (Extended to Ch1 ~ Ch2)
mfurukawa 3:07aa20aa678d 7 *
mfurukawa 3:07aa20aa678d 8 **/
mfurukawa 3:07aa20aa678d 9
adisuciu 0:83fda1bfaffe 10 #include "mbed.h"
mfurukawa 6:ea0804dc7cae 11 #include "MPU9250.h"
mfurukawa 10:28fa811afbfb 12 #include "KalmanFilter.h"
mfurukawa 12:5638ddcd8477 13
mfurukawa 12:5638ddcd8477 14
mfurukawa 12:5638ddcd8477 15 /* MPU9250 Library
mfurukawa 12:5638ddcd8477 16 *
mfurukawa 12:5638ddcd8477 17 * https://developer.mbed.org/users/kylongmu/code/MPU9250_SPI_Test/file/5839d1b118bc/main.cpp
mfurukawa 12:5638ddcd8477 18
mfurukawa 1:f1e4ee4fc335 19 MOSI (Master Out Slave In) p5
mfurukawa 1:f1e4ee4fc335 20 MISO (Master In Slave Out p6
mfurukawa 1:f1e4ee4fc335 21 SCK (Serial Clock) p7
mfurukawa 6:ea0804dc7cae 22 ~CS (Chip Select) p8
mfurukawa 12:5638ddcd8477 23 */
mfurukawa 10:28fa811afbfb 24
mfurukawa 12:5638ddcd8477 25 /* Reference
mfurukawa 12:5638ddcd8477 26 *
mfurukawa 12:5638ddcd8477 27 * AHRS algorithm is one of hte sensor fusion algorism.
mfurukawa 12:5638ddcd8477 28 * http://www.x-io.co.uk/open-source-imu-and-ahrs-algorithms/AHRS algorithm is one of hte sensor fusion algorism.
mfurukawa 12:5638ddcd8477 29 * http://www.x-io.co.uk/open-source-imu-and-ahrs-algorithms/
mfurukawa 12:5638ddcd8477 30 */
mfurukawa 12:5638ddcd8477 31
mfurukawa 10:28fa811afbfb 32 //---------------------------------------------------------------------------------------------------
mfurukawa 10:28fa811afbfb 33 // Definitions
mfurukawa 10:28fa811afbfb 34
mfurukawa 10:28fa811afbfb 35 #define sampleFreq 500.0f // sample frequency in Hz
mfurukawa 10:28fa811afbfb 36 #define betaDef 1.0f // 2 * proportional gain
mfurukawa 10:28fa811afbfb 37 #define PI 3.14159265358979f
mfurukawa 10:28fa811afbfb 38 #define DEGREE2RAD PI/180.0f
mfurukawa 12:5638ddcd8477 39 class MadgwickAHRS
mfurukawa 12:5638ddcd8477 40 {
mfurukawa 10:28fa811afbfb 41 //---------------------------------------------------------------------------------------------------
mfurukawa 10:28fa811afbfb 42 // Variable definitions
mfurukawa 10:28fa811afbfb 43
mfurukawa 12:5638ddcd8477 44 private:
mfurukawa 12:5638ddcd8477 45 volatile float beta; // 2 * proportional gain (Kp)
mfurukawa 12:5638ddcd8477 46
mfurukawa 10:28fa811afbfb 47 //---------------------------------------------------------------------------------------------------
mfurukawa 10:28fa811afbfb 48 // Function declarations
mfurukawa 12:5638ddcd8477 49 public:
mfurukawa 12:5638ddcd8477 50 volatile float q0,q1,q2,q3; // quaternion of sensor frame relative to auxiliary frame
mfurukawa 10:28fa811afbfb 51
mfurukawa 12:5638ddcd8477 52 MadgwickAHRS();
mfurukawa 12:5638ddcd8477 53 void update(float gx, float gy, float gz, float ax, float ay, float az, float mx, float my, float mz);
mfurukawa 12:5638ddcd8477 54 void updateIMU(float gx, float gy, float gz, float ax, float ay, float az);
mfurukawa 12:5638ddcd8477 55 float invSqrt(float x);
mfurukawa 12:5638ddcd8477 56 };
mfurukawa 10:28fa811afbfb 57 //====================================================================================================
mfurukawa 10:28fa811afbfb 58 // Functions
mfurukawa 10:28fa811afbfb 59
mfurukawa 10:28fa811afbfb 60 //---------------------------------------------------------------------------------------------------
mfurukawa 10:28fa811afbfb 61 // AHRS algorithm update
mfurukawa 12:5638ddcd8477 62 MadgwickAHRS::MadgwickAHRS()
mfurukawa 12:5638ddcd8477 63 {
mfurukawa 12:5638ddcd8477 64 beta = betaDef; // 2 * proportional gain (Kp)
mfurukawa 12:5638ddcd8477 65 q0 = 1.0f;
mfurukawa 12:5638ddcd8477 66 q1 = 0.0f;
mfurukawa 12:5638ddcd8477 67 q2 = 0.0f;
mfurukawa 12:5638ddcd8477 68 q3 = 0.0f; // quaternion of sensor frame relative to auxiliary frame
mfurukawa 12:5638ddcd8477 69 }
mfurukawa 12:5638ddcd8477 70 void MadgwickAHRS::update(float gx, float gy, float gz, float ax, float ay, float az, float mx, float my, float mz)
mfurukawa 11:3f0b35a0855c 71 {
mfurukawa 10:28fa811afbfb 72 float recipNorm;
mfurukawa 10:28fa811afbfb 73 float s0, s1, s2, s3;
mfurukawa 10:28fa811afbfb 74 float qDot1, qDot2, qDot3, qDot4;
mfurukawa 10:28fa811afbfb 75 float hx, hy;
mfurukawa 10:28fa811afbfb 76 float _2q0mx, _2q0my, _2q0mz, _2q1mx, _2bx, _2bz, _4bx, _4bz, _2q0, _2q1, _2q2, _2q3, _2q0q2, _2q2q3, q0q0, q0q1, q0q2, q0q3, q1q1, q1q2, q1q3, q2q2, q2q3, q3q3;
mfurukawa 10:28fa811afbfb 77
mfurukawa 10:28fa811afbfb 78 // Use IMU algorithm if magnetometer measurement invalid (avoids NaN in magnetometer normalisation)
mfurukawa 10:28fa811afbfb 79 if((mx == 0.0f) && (my == 0.0f) && (mz == 0.0f)) {
mfurukawa 12:5638ddcd8477 80 updateIMU(gx, gy, gz, ax, ay, az);
mfurukawa 10:28fa811afbfb 81 return;
mfurukawa 10:28fa811afbfb 82 }
mfurukawa 10:28fa811afbfb 83
mfurukawa 10:28fa811afbfb 84 // Rate of change of quaternion from gyroscope
mfurukawa 10:28fa811afbfb 85 qDot1 = 0.5f * (-q1 * gx - q2 * gy - q3 * gz);
mfurukawa 10:28fa811afbfb 86 qDot2 = 0.5f * (q0 * gx + q2 * gz - q3 * gy);
mfurukawa 10:28fa811afbfb 87 qDot3 = 0.5f * (q0 * gy - q1 * gz + q3 * gx);
mfurukawa 10:28fa811afbfb 88 qDot4 = 0.5f * (q0 * gz + q1 * gy - q2 * gx);
mfurukawa 10:28fa811afbfb 89
mfurukawa 10:28fa811afbfb 90 // Compute feedback only if accelerometer measurement valid (avoids NaN in accelerometer normalisation)
mfurukawa 10:28fa811afbfb 91 if(!((ax == 0.0f) && (ay == 0.0f) && (az == 0.0f))) {
mfurukawa 6:ea0804dc7cae 92
mfurukawa 10:28fa811afbfb 93 // Normalise accelerometer measurement
mfurukawa 10:28fa811afbfb 94 recipNorm = invSqrt(ax * ax + ay * ay + az * az);
mfurukawa 10:28fa811afbfb 95 ax *= recipNorm;
mfurukawa 10:28fa811afbfb 96 ay *= recipNorm;
mfurukawa 11:3f0b35a0855c 97 az *= recipNorm;
mfurukawa 10:28fa811afbfb 98
mfurukawa 10:28fa811afbfb 99 // Normalise magnetometer measurement
mfurukawa 10:28fa811afbfb 100 recipNorm = invSqrt(mx * mx + my * my + mz * mz);
mfurukawa 10:28fa811afbfb 101 mx *= recipNorm;
mfurukawa 10:28fa811afbfb 102 my *= recipNorm;
mfurukawa 10:28fa811afbfb 103 mz *= recipNorm;
mfurukawa 10:28fa811afbfb 104
mfurukawa 10:28fa811afbfb 105 // Auxiliary variables to avoid repeated arithmetic
mfurukawa 10:28fa811afbfb 106 _2q0mx = 2.0f * q0 * mx;
mfurukawa 10:28fa811afbfb 107 _2q0my = 2.0f * q0 * my;
mfurukawa 10:28fa811afbfb 108 _2q0mz = 2.0f * q0 * mz;
mfurukawa 10:28fa811afbfb 109 _2q1mx = 2.0f * q1 * mx;
mfurukawa 10:28fa811afbfb 110 _2q0 = 2.0f * q0;
mfurukawa 10:28fa811afbfb 111 _2q1 = 2.0f * q1;
mfurukawa 10:28fa811afbfb 112 _2q2 = 2.0f * q2;
mfurukawa 10:28fa811afbfb 113 _2q3 = 2.0f * q3;
mfurukawa 10:28fa811afbfb 114 _2q0q2 = 2.0f * q0 * q2;
mfurukawa 10:28fa811afbfb 115 _2q2q3 = 2.0f * q2 * q3;
mfurukawa 10:28fa811afbfb 116 q0q0 = q0 * q0;
mfurukawa 10:28fa811afbfb 117 q0q1 = q0 * q1;
mfurukawa 10:28fa811afbfb 118 q0q2 = q0 * q2;
mfurukawa 10:28fa811afbfb 119 q0q3 = q0 * q3;
mfurukawa 10:28fa811afbfb 120 q1q1 = q1 * q1;
mfurukawa 10:28fa811afbfb 121 q1q2 = q1 * q2;
mfurukawa 10:28fa811afbfb 122 q1q3 = q1 * q3;
mfurukawa 10:28fa811afbfb 123 q2q2 = q2 * q2;
mfurukawa 10:28fa811afbfb 124 q2q3 = q2 * q3;
mfurukawa 10:28fa811afbfb 125 q3q3 = q3 * q3;
mfurukawa 10:28fa811afbfb 126
mfurukawa 10:28fa811afbfb 127 // Reference direction of Earth's magnetic field
mfurukawa 10:28fa811afbfb 128 hx = mx * q0q0 - _2q0my * q3 + _2q0mz * q2 + mx * q1q1 + _2q1 * my * q2 + _2q1 * mz * q3 - mx * q2q2 - mx * q3q3;
mfurukawa 10:28fa811afbfb 129 hy = _2q0mx * q3 + my * q0q0 - _2q0mz * q1 + _2q1mx * q2 - my * q1q1 + my * q2q2 + _2q2 * mz * q3 - my * q3q3;
mfurukawa 10:28fa811afbfb 130 _2bx = sqrt(hx * hx + hy * hy);
mfurukawa 10:28fa811afbfb 131 _2bz = -_2q0mx * q2 + _2q0my * q1 + mz * q0q0 + _2q1mx * q3 - mz * q1q1 + _2q2 * my * q3 - mz * q2q2 + mz * q3q3;
mfurukawa 10:28fa811afbfb 132 _4bx = 2.0f * _2bx;
mfurukawa 10:28fa811afbfb 133 _4bz = 2.0f * _2bz;
mfurukawa 10:28fa811afbfb 134
mfurukawa 10:28fa811afbfb 135 // Gradient decent algorithm corrective step
mfurukawa 10:28fa811afbfb 136 s0 = -_2q2 * (2.0f * q1q3 - _2q0q2 - ax) + _2q1 * (2.0f * q0q1 + _2q2q3 - ay) - _2bz * q2 * (_2bx * (0.5f - q2q2 - q3q3) + _2bz * (q1q3 - q0q2) - mx) + (-_2bx * q3 + _2bz * q1) * (_2bx * (q1q2 - q0q3) + _2bz * (q0q1 + q2q3) - my) + _2bx * q2 * (_2bx * (q0q2 + q1q3) + _2bz * (0.5f - q1q1 - q2q2) - mz);
mfurukawa 10:28fa811afbfb 137 s1 = _2q3 * (2.0f * q1q3 - _2q0q2 - ax) + _2q0 * (2.0f * q0q1 + _2q2q3 - ay) - 4.0f * q1 * (1 - 2.0f * q1q1 - 2.0f * q2q2 - az) + _2bz * q3 * (_2bx * (0.5f - q2q2 - q3q3) + _2bz * (q1q3 - q0q2) - mx) + (_2bx * q2 + _2bz * q0) * (_2bx * (q1q2 - q0q3) + _2bz * (q0q1 + q2q3) - my) + (_2bx * q3 - _4bz * q1) * (_2bx * (q0q2 + q1q3) + _2bz * (0.5f - q1q1 - q2q2) - mz);
mfurukawa 10:28fa811afbfb 138 s2 = -_2q0 * (2.0f * q1q3 - _2q0q2 - ax) + _2q3 * (2.0f * q0q1 + _2q2q3 - ay) - 4.0f * q2 * (1 - 2.0f * q1q1 - 2.0f * q2q2 - az) + (-_4bx * q2 - _2bz * q0) * (_2bx * (0.5f - q2q2 - q3q3) + _2bz * (q1q3 - q0q2) - mx) + (_2bx * q1 + _2bz * q3) * (_2bx * (q1q2 - q0q3) + _2bz * (q0q1 + q2q3) - my) + (_2bx * q0 - _4bz * q2) * (_2bx * (q0q2 + q1q3) + _2bz * (0.5f - q1q1 - q2q2) - mz);
mfurukawa 10:28fa811afbfb 139 s3 = _2q1 * (2.0f * q1q3 - _2q0q2 - ax) + _2q2 * (2.0f * q0q1 + _2q2q3 - ay) + (-_4bx * q3 + _2bz * q1) * (_2bx * (0.5f - q2q2 - q3q3) + _2bz * (q1q3 - q0q2) - mx) + (-_2bx * q0 + _2bz * q2) * (_2bx * (q1q2 - q0q3) + _2bz * (q0q1 + q2q3) - my) + _2bx * q1 * (_2bx * (q0q2 + q1q3) + _2bz * (0.5f - q1q1 - q2q2) - mz);
mfurukawa 10:28fa811afbfb 140 recipNorm = invSqrt(s0 * s0 + s1 * s1 + s2 * s2 + s3 * s3); // normalise step magnitude
mfurukawa 10:28fa811afbfb 141 s0 *= recipNorm;
mfurukawa 10:28fa811afbfb 142 s1 *= recipNorm;
mfurukawa 10:28fa811afbfb 143 s2 *= recipNorm;
mfurukawa 10:28fa811afbfb 144 s3 *= recipNorm;
mfurukawa 10:28fa811afbfb 145
mfurukawa 10:28fa811afbfb 146 // Apply feedback step
mfurukawa 10:28fa811afbfb 147 qDot1 -= beta * s0;
mfurukawa 10:28fa811afbfb 148 qDot2 -= beta * s1;
mfurukawa 10:28fa811afbfb 149 qDot3 -= beta * s2;
mfurukawa 10:28fa811afbfb 150 qDot4 -= beta * s3;
mfurukawa 10:28fa811afbfb 151 }
mfurukawa 8:03f9b5289083 152
mfurukawa 10:28fa811afbfb 153 // Integrate rate of change of quaternion to yield quaternion
mfurukawa 10:28fa811afbfb 154 q0 += qDot1 * (1.0f / sampleFreq);
mfurukawa 10:28fa811afbfb 155 q1 += qDot2 * (1.0f / sampleFreq);
mfurukawa 10:28fa811afbfb 156 q2 += qDot3 * (1.0f / sampleFreq);
mfurukawa 10:28fa811afbfb 157 q3 += qDot4 * (1.0f / sampleFreq);
mfurukawa 10:28fa811afbfb 158
mfurukawa 10:28fa811afbfb 159 // Normalise quaternion
mfurukawa 10:28fa811afbfb 160 recipNorm = invSqrt(q0 * q0 + q1 * q1 + q2 * q2 + q3 * q3);
mfurukawa 10:28fa811afbfb 161 q0 *= recipNorm;
mfurukawa 10:28fa811afbfb 162 q1 *= recipNorm;
mfurukawa 10:28fa811afbfb 163 q2 *= recipNorm;
mfurukawa 10:28fa811afbfb 164 q3 *= recipNorm;
mfurukawa 10:28fa811afbfb 165 }
mfurukawa 10:28fa811afbfb 166
mfurukawa 10:28fa811afbfb 167 //---------------------------------------------------------------------------------------------------
mfurukawa 10:28fa811afbfb 168 // IMU algorithm update
mfurukawa 10:28fa811afbfb 169
mfurukawa 12:5638ddcd8477 170 void MadgwickAHRS::updateIMU(float gx, float gy, float gz, float ax, float ay, float az)
mfurukawa 11:3f0b35a0855c 171 {
mfurukawa 10:28fa811afbfb 172 float recipNorm;
mfurukawa 10:28fa811afbfb 173 float s0, s1, s2, s3;
mfurukawa 10:28fa811afbfb 174 float qDot1, qDot2, qDot3, qDot4;
mfurukawa 10:28fa811afbfb 175 float _2q0, _2q1, _2q2, _2q3, _4q0, _4q1, _4q2 ,_8q1, _8q2, q0q0, q1q1, q2q2, q3q3;
mfurukawa 10:28fa811afbfb 176
mfurukawa 10:28fa811afbfb 177 // Rate of change of quaternion from gyroscope
mfurukawa 10:28fa811afbfb 178 qDot1 = 0.5f * (-q1 * gx - q2 * gy - q3 * gz);
mfurukawa 10:28fa811afbfb 179 qDot2 = 0.5f * (q0 * gx + q2 * gz - q3 * gy);
mfurukawa 10:28fa811afbfb 180 qDot3 = 0.5f * (q0 * gy - q1 * gz + q3 * gx);
mfurukawa 10:28fa811afbfb 181 qDot4 = 0.5f * (q0 * gz + q1 * gy - q2 * gx);
mfurukawa 10:28fa811afbfb 182
mfurukawa 10:28fa811afbfb 183 // Compute feedback only if accelerometer measurement valid (avoids NaN in accelerometer normalisation)
mfurukawa 10:28fa811afbfb 184 if(!((ax == 0.0f) && (ay == 0.0f) && (az == 0.0f))) {
mfurukawa 10:28fa811afbfb 185
mfurukawa 10:28fa811afbfb 186 // Normalise accelerometer measurement
mfurukawa 10:28fa811afbfb 187 recipNorm = invSqrt(ax * ax + ay * ay + az * az);
mfurukawa 10:28fa811afbfb 188 ax *= recipNorm;
mfurukawa 10:28fa811afbfb 189 ay *= recipNorm;
mfurukawa 11:3f0b35a0855c 190 az *= recipNorm;
mfurukawa 10:28fa811afbfb 191
mfurukawa 10:28fa811afbfb 192 // Auxiliary variables to avoid repeated arithmetic
mfurukawa 10:28fa811afbfb 193 _2q0 = 2.0f * q0;
mfurukawa 10:28fa811afbfb 194 _2q1 = 2.0f * q1;
mfurukawa 10:28fa811afbfb 195 _2q2 = 2.0f * q2;
mfurukawa 10:28fa811afbfb 196 _2q3 = 2.0f * q3;
mfurukawa 10:28fa811afbfb 197 _4q0 = 4.0f * q0;
mfurukawa 10:28fa811afbfb 198 _4q1 = 4.0f * q1;
mfurukawa 10:28fa811afbfb 199 _4q2 = 4.0f * q2;
mfurukawa 10:28fa811afbfb 200 _8q1 = 8.0f * q1;
mfurukawa 10:28fa811afbfb 201 _8q2 = 8.0f * q2;
mfurukawa 10:28fa811afbfb 202 q0q0 = q0 * q0;
mfurukawa 10:28fa811afbfb 203 q1q1 = q1 * q1;
mfurukawa 10:28fa811afbfb 204 q2q2 = q2 * q2;
mfurukawa 10:28fa811afbfb 205 q3q3 = q3 * q3;
mfurukawa 6:ea0804dc7cae 206
mfurukawa 10:28fa811afbfb 207 // Gradient decent algorithm corrective step
mfurukawa 10:28fa811afbfb 208 s0 = _4q0 * q2q2 + _2q2 * ax + _4q0 * q1q1 - _2q1 * ay;
mfurukawa 10:28fa811afbfb 209 s1 = _4q1 * q3q3 - _2q3 * ax + 4.0f * q0q0 * q1 - _2q0 * ay - _4q1 + _8q1 * q1q1 + _8q1 * q2q2 + _4q1 * az;
mfurukawa 10:28fa811afbfb 210 s2 = 4.0f * q0q0 * q2 + _2q0 * ax + _4q2 * q3q3 - _2q3 * ay - _4q2 + _8q2 * q1q1 + _8q2 * q2q2 + _4q2 * az;
mfurukawa 10:28fa811afbfb 211 s3 = 4.0f * q1q1 * q3 - _2q1 * ax + 4.0f * q2q2 * q3 - _2q2 * ay;
mfurukawa 10:28fa811afbfb 212 recipNorm = invSqrt(s0 * s0 + s1 * s1 + s2 * s2 + s3 * s3); // normalise step magnitude
mfurukawa 10:28fa811afbfb 213 s0 *= recipNorm;
mfurukawa 10:28fa811afbfb 214 s1 *= recipNorm;
mfurukawa 10:28fa811afbfb 215 s2 *= recipNorm;
mfurukawa 10:28fa811afbfb 216 s3 *= recipNorm;
mfurukawa 10:28fa811afbfb 217
mfurukawa 10:28fa811afbfb 218 // Apply feedback step
mfurukawa 10:28fa811afbfb 219 qDot1 -= beta * s0;
mfurukawa 10:28fa811afbfb 220 qDot2 -= beta * s1;
mfurukawa 10:28fa811afbfb 221 qDot3 -= beta * s2;
mfurukawa 10:28fa811afbfb 222 qDot4 -= beta * s3;
mfurukawa 10:28fa811afbfb 223 }
mfurukawa 10:28fa811afbfb 224
mfurukawa 10:28fa811afbfb 225 // Integrate rate of change of quaternion to yield quaternion
mfurukawa 10:28fa811afbfb 226 q0 += qDot1 * (1.0f / sampleFreq);
mfurukawa 10:28fa811afbfb 227 q1 += qDot2 * (1.0f / sampleFreq);
mfurukawa 10:28fa811afbfb 228 q2 += qDot3 * (1.0f / sampleFreq);
mfurukawa 10:28fa811afbfb 229 q3 += qDot4 * (1.0f / sampleFreq);
mfurukawa 8:03f9b5289083 230
mfurukawa 10:28fa811afbfb 231 // Normalise quaternion
mfurukawa 10:28fa811afbfb 232 recipNorm = invSqrt(q0 * q0 + q1 * q1 + q2 * q2 + q3 * q3);
mfurukawa 10:28fa811afbfb 233 q0 *= recipNorm;
mfurukawa 10:28fa811afbfb 234 q1 *= recipNorm;
mfurukawa 10:28fa811afbfb 235 q2 *= recipNorm;
mfurukawa 10:28fa811afbfb 236 q3 *= recipNorm;
mfurukawa 10:28fa811afbfb 237 }
mfurukawa 10:28fa811afbfb 238
mfurukawa 10:28fa811afbfb 239 //---------------------------------------------------------------------------------------------------
mfurukawa 10:28fa811afbfb 240 // Fast inverse square-root
mfurukawa 10:28fa811afbfb 241 // See: http://en.wikipedia.org/wiki/Fast_inverse_square_root
mfurukawa 10:28fa811afbfb 242
mfurukawa 12:5638ddcd8477 243 float MadgwickAHRS::invSqrt(float x)
mfurukawa 11:3f0b35a0855c 244 {
mfurukawa 10:28fa811afbfb 245 float halfx = 0.5f * x;
mfurukawa 10:28fa811afbfb 246 float y = x;
mfurukawa 10:28fa811afbfb 247 long i = *(long*)&y;
mfurukawa 10:28fa811afbfb 248 i = 0x5f3759df - (i>>1);
mfurukawa 10:28fa811afbfb 249 y = *(float*)&i;
mfurukawa 10:28fa811afbfb 250 y = y * (1.5f - (halfx * y * y));
mfurukawa 10:28fa811afbfb 251 return y;
mfurukawa 10:28fa811afbfb 252 }
mfurukawa 10:28fa811afbfb 253
mfurukawa 10:28fa811afbfb 254
mfurukawa 10:28fa811afbfb 255
mfurukawa 10:28fa811afbfb 256 //define the mpu9250 object
mfurukawa 10:28fa811afbfb 257 mpu9250_spi *imu[2];
mfurukawa 12:5638ddcd8477 258 MadgwickAHRS *ahrs[2];
mfurukawa 10:28fa811afbfb 259 Serial pc(USBTX, USBRX);
mfurukawa 10:28fa811afbfb 260 SPI spi(p5, p6, p7);
mfurukawa 10:28fa811afbfb 261 KalmanFilter *kf[12];
mfurukawa 10:28fa811afbfb 262 Ticker ticker;
mfurukawa 10:28fa811afbfb 263
mfurukawa 10:28fa811afbfb 264 float x,y,z,gxOfs,gyOfs,gzOfs;
mfurukawa 10:28fa811afbfb 265 // Calibration wait
mfurukawa 10:28fa811afbfb 266
mfurukawa 12:5638ddcd8477 267 void resetOffset(void)
mfurukawa 11:3f0b35a0855c 268 {
mfurukawa 11:3f0b35a0855c 269
mfurukawa 12:5638ddcd8477 270 gxOfs = 0.0f;
mfurukawa 12:5638ddcd8477 271 gyOfs = 0.0f;
mfurukawa 12:5638ddcd8477 272 gzOfs = 0.0f;
mfurukawa 11:3f0b35a0855c 273
mfurukawa 11:3f0b35a0855c 274 imu[0]->deselect();
mfurukawa 11:3f0b35a0855c 275 imu[1]->deselect();
mfurukawa 11:3f0b35a0855c 276
mfurukawa 11:3f0b35a0855c 277 imu[0]->select();
mfurukawa 11:3f0b35a0855c 278
mfurukawa 11:3f0b35a0855c 279 for(int i=0; i<1000; i++) {
mfurukawa 11:3f0b35a0855c 280
mfurukawa 11:3f0b35a0855c 281 imu[0]->read_all();
mfurukawa 11:3f0b35a0855c 282
mfurukawa 11:3f0b35a0855c 283 gxOfs += imu[0]->gyroscope_data[0];
mfurukawa 11:3f0b35a0855c 284 gyOfs += imu[0]->gyroscope_data[1];
mfurukawa 11:3f0b35a0855c 285 gzOfs += imu[0]->gyroscope_data[2];
mfurukawa 11:3f0b35a0855c 286
mfurukawa 11:3f0b35a0855c 287 wait_us(1000000.0f/sampleFreq);
mfurukawa 11:3f0b35a0855c 288 }
mfurukawa 11:3f0b35a0855c 289
mfurukawa 12:5638ddcd8477 290 gxOfs /= 1000.0f;
mfurukawa 12:5638ddcd8477 291 gyOfs /= 1000.0f;
mfurukawa 12:5638ddcd8477 292 gzOfs /= 1000.0f;
mfurukawa 11:3f0b35a0855c 293
mfurukawa 12:5638ddcd8477 294 ahrs[0]->q0 = 1.0f;
mfurukawa 12:5638ddcd8477 295 ahrs[0]->q1 = 0.0f;
mfurukawa 12:5638ddcd8477 296 ahrs[0]->q2 = 0.0f;
mfurukawa 12:5638ddcd8477 297 ahrs[0]->q3 = 0.0f;
mfurukawa 11:3f0b35a0855c 298 }
mfurukawa 11:3f0b35a0855c 299
mfurukawa 11:3f0b35a0855c 300 void init(void)
mfurukawa 11:3f0b35a0855c 301 {
mfurukawa 11:3f0b35a0855c 302
mfurukawa 10:28fa811afbfb 303 pc.baud(921600);
mfurukawa 11:3f0b35a0855c 304
mfurukawa 6:ea0804dc7cae 305 imu[0] = new mpu9250_spi(spi, p8);
mfurukawa 6:ea0804dc7cae 306 imu[1] = new mpu9250_spi(spi, p9);
mfurukawa 11:3f0b35a0855c 307
mfurukawa 12:5638ddcd8477 308 ahrs[0] = new MadgwickAHRS();
mfurukawa 12:5638ddcd8477 309 ahrs[1] = new MadgwickAHRS();
mfurukawa 11:3f0b35a0855c 310
mfurukawa 8:03f9b5289083 311 for(int i=0; i<2; i++) {
mfurukawa 11:3f0b35a0855c 312
mfurukawa 7:758a94e02aa7 313 imu[0]->deselect();
mfurukawa 7:758a94e02aa7 314 imu[1]->deselect();
mfurukawa 7:758a94e02aa7 315 imu[i]->select();
mfurukawa 8:03f9b5289083 316
mfurukawa 8:03f9b5289083 317 if(imu[i]->init(1,BITS_DLPF_CFG_188HZ)) { //INIT the mpu9250
mfurukawa 12:5638ddcd8477 318 printf("\nCH %d\n\nCouldn't initialize MPU9250 via SPI!", i);
mfurukawa 10:28fa811afbfb 319 wait(90);
mfurukawa 8:03f9b5289083 320 }
mfurukawa 12:5638ddcd8477 321 printf("\nCH %d\nWHOAMI=0x%2x\n",i, imu[i]->whoami()); //output the I2C address to know if SPI is working, it should be 104
mfurukawa 10:28fa811afbfb 322 printf("Gyro_scale=%u\n",imu[i]->set_gyro_scale(BITS_FS_1000DPS)); //Set full scale range for gyros
mfurukawa 6:ea0804dc7cae 323 printf("Acc_scale=%u\n",imu[i]->set_acc_scale(BITS_FS_16G)); //Set full scale range for accs
mfurukawa 6:ea0804dc7cae 324 printf("AK8963 WHIAM=0x%2x\n",imu[i]->AK8963_whoami());
mfurukawa 6:ea0804dc7cae 325 imu[i]->AK8963_calib_Magnetometer();
mfurukawa 8:03f9b5289083 326 wait(0.1);
mfurukawa 7:758a94e02aa7 327 }
mfurukawa 12:5638ddcd8477 328 resetOffset();
mfurukawa 10:28fa811afbfb 329 }
mfurukawa 8:03f9b5289083 330
mfurukawa 10:28fa811afbfb 331 void eventFunc(void)
mfurukawa 10:28fa811afbfb 332 {
mfurukawa 12:5638ddcd8477 333 for(int i=0; i<2; i++) {
mfurukawa 11:3f0b35a0855c 334
mfurukawa 10:28fa811afbfb 335 imu[0]->deselect();
mfurukawa 10:28fa811afbfb 336 imu[1]->deselect();
mfurukawa 11:3f0b35a0855c 337
mfurukawa 10:28fa811afbfb 338 imu[i]->select();
mfurukawa 10:28fa811afbfb 339 imu[i]->read_all();
mfurukawa 12:5638ddcd8477 340 }
mfurukawa 12:5638ddcd8477 341 for(int i=0; i<2; i++) {
mfurukawa 12:5638ddcd8477 342 ahrs[i]->update(
mfurukawa 10:28fa811afbfb 343 (imu[i]->gyroscope_data[0]-gxOfs)*DEGREE2RAD,
mfurukawa 10:28fa811afbfb 344 (imu[i]->gyroscope_data[1]-gyOfs)*DEGREE2RAD,
mfurukawa 10:28fa811afbfb 345 (imu[i]->gyroscope_data[2]-gzOfs)*DEGREE2RAD,
mfurukawa 10:28fa811afbfb 346 imu[i]->accelerometer_data[0],
mfurukawa 10:28fa811afbfb 347 imu[i]->accelerometer_data[1],
mfurukawa 10:28fa811afbfb 348 imu[i]->accelerometer_data[2],
mfurukawa 10:28fa811afbfb 349 imu[i]->Magnetometer[0],
mfurukawa 10:28fa811afbfb 350 imu[i]->Magnetometer[1],
mfurukawa 10:28fa811afbfb 351 imu[i]->Magnetometer[2]
mfurukawa 10:28fa811afbfb 352 );
mfurukawa 11:3f0b35a0855c 353
mfurukawa 12:5638ddcd8477 354 printf("%+0.3f,%+0.3f,%+0.3f,%+0.3f,",
mfurukawa 12:5638ddcd8477 355 ahrs[i]->q0,ahrs[i]->q1,ahrs[i]->q2,ahrs[i]->q3);
mfurukawa 11:3f0b35a0855c 356 }
mfurukawa 12:5638ddcd8477 357 printf("\n");
mfurukawa 10:28fa811afbfb 358 }
mfurukawa 10:28fa811afbfb 359
mfurukawa 10:28fa811afbfb 360 int main()
mfurukawa 10:28fa811afbfb 361 {
mfurukawa 10:28fa811afbfb 362 init();
mfurukawa 11:3f0b35a0855c 363
mfurukawa 11:3f0b35a0855c 364 ticker.attach_us(eventFunc, 1000000.0f/sampleFreq);
mfurukawa 11:3f0b35a0855c 365
mfurukawa 10:28fa811afbfb 366 while(1) {
mfurukawa 11:3f0b35a0855c 367
mfurukawa 11:3f0b35a0855c 368 if(pc.readable())
mfurukawa 11:3f0b35a0855c 369 if(pc.getc() == 'r') {
mfurukawa 11:3f0b35a0855c 370 ticker.detach();
mfurukawa 12:5638ddcd8477 371 resetOffset();
mfurukawa 11:3f0b35a0855c 372 ticker.attach_us(eventFunc, 1000000.0f/sampleFreq);
mfurukawa 11:3f0b35a0855c 373 }
mfurukawa 11:3f0b35a0855c 374 /*
mfurukawa 11:3f0b35a0855c 375 imu[i]->read_all();
mfurukawa 11:3f0b35a0855c 376 printf("%10.3f,%10.3f,%10.3f,%10.3f,%10.3f,%10.3f,%10.3f,%10.3f,%10.3f,%10.3f ",
mfurukawa 11:3f0b35a0855c 377 imu[i]->Temperature,
mfurukawa 11:3f0b35a0855c 378 imu[i]->gyroscope_data[0],
mfurukawa 11:3f0b35a0855c 379 imu[i]->gyroscope_data[1],
mfurukawa 11:3f0b35a0855c 380 imu[i]->gyroscope_data[2],
mfurukawa 11:3f0b35a0855c 381 imu[i]->accelerometer_data[0],
mfurukawa 11:3f0b35a0855c 382 imu[i]->accelerometer_data[1],
mfurukawa 11:3f0b35a0855c 383 imu[i]->accelerometer_data[2],
mfurukawa 11:3f0b35a0855c 384 imu[i]->Magnetometer[0],
mfurukawa 11:3f0b35a0855c 385 imu[i]->Magnetometer[1],
mfurukawa 11:3f0b35a0855c 386 imu[i]->Magnetometer[2]
mfurukawa 11:3f0b35a0855c 387 );*/
mfurukawa 11:3f0b35a0855c 388 //myled = 0;
mfurukawa 11:3f0b35a0855c 389 //wait(0.5);
adisuciu 0:83fda1bfaffe 390 }
adisuciu 0:83fda1bfaffe 391 }