Implemented first Hangar-Service
Dependencies: CalibrateMagneto QuaternionMath
Fork of SML2 by
SensorFusion.cpp@41:731e3cfac19b, 2015-05-20 (annotated)
- Committer:
- uadhikari
- Date:
- Wed May 20 10:13:14 2015 +0000
- Revision:
- 41:731e3cfac19b
- Parent:
- 39:1fa9c0e1ffde
- Child:
- 42:160a37bdaa64
Refactored SensorFusion class
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
pvaibhav | 15:4488660e1a3b | 1 | #include "SensorFusion.h" |
pvaibhav | 15:4488660e1a3b | 2 | |
pvaibhav | 15:4488660e1a3b | 3 | #define DEBUG "SensorFusion" |
pvaibhav | 15:4488660e1a3b | 4 | #include "Logger.h" |
pvaibhav | 15:4488660e1a3b | 5 | |
pvaibhav | 34:01dec68de3ed | 6 | #include "Utils.h" |
pvaibhav | 39:1fa9c0e1ffde | 7 | #define SIXAXIS |
pvaibhav | 34:01dec68de3ed | 8 | |
pvaibhav | 21:5a0c9406e119 | 9 | SensorFusion::SensorFusion(I2C &i2c) : |
pvaibhav | 21:5a0c9406e119 | 10 | delegate(&defaultDelegate), |
pvaibhav | 21:5a0c9406e119 | 11 | accel(i2c), gyro(i2c), magneto(i2c), |
pvaibhav | 15:4488660e1a3b | 12 | q(1, 0, 0, 0), // output quaternion |
pvaibhav | 15:4488660e1a3b | 13 | deltat(0.010), // sec |
pvaibhav | 39:1fa9c0e1ffde | 14 | beta(0.3), // correction gain |
pvaibhav | 34:01dec68de3ed | 15 | fused(0, 0, 0) |
pvaibhav | 15:4488660e1a3b | 16 | { |
pvaibhav | 20:503cbe360419 | 17 | } |
pvaibhav | 20:503cbe360419 | 18 | |
uadhikari | 41:731e3cfac19b | 19 | SensorFusion::SensorFusion(const SensorFusion& s) : |
uadhikari | 41:731e3cfac19b | 20 | delegate(s.delegate), |
uadhikari | 41:731e3cfac19b | 21 | accel(s.accel), |
uadhikari | 41:731e3cfac19b | 22 | gyro(s.gyro), |
uadhikari | 41:731e3cfac19b | 23 | magneto(s.magneto), |
uadhikari | 41:731e3cfac19b | 24 | q(s.q), |
uadhikari | 41:731e3cfac19b | 25 | deltat(s.deltat), |
uadhikari | 41:731e3cfac19b | 26 | beta(s.beta), |
uadhikari | 41:731e3cfac19b | 27 | fused(s.fused) |
uadhikari | 41:731e3cfac19b | 28 | {} |
uadhikari | 41:731e3cfac19b | 29 | |
uadhikari | 41:731e3cfac19b | 30 | SensorFusion::~SensorFusion(){}; |
uadhikari | 41:731e3cfac19b | 31 | |
uadhikari | 41:731e3cfac19b | 32 | |
uadhikari | 41:731e3cfac19b | 33 | SixAxesSensor::~SixAxesSensor(){}; |
uadhikari | 41:731e3cfac19b | 34 | |
uadhikari | 41:731e3cfac19b | 35 | NineAxesSensor::~NineAxesSensor(){}; |
uadhikari | 41:731e3cfac19b | 36 | |
uadhikari | 41:731e3cfac19b | 37 | NineAxesSensor::NineAxesSensor(const NineAxesSensor& c) : SensorFusion(c){}; |
uadhikari | 41:731e3cfac19b | 38 | |
uadhikari | 41:731e3cfac19b | 39 | SixAxesSensor::SixAxesSensor(const SixAxesSensor& c) : SensorFusion(c){}; |
uadhikari | 41:731e3cfac19b | 40 | |
pvaibhav | 20:503cbe360419 | 41 | void SensorFusion::setDelegate(SensorFusion::Delegate &d) |
pvaibhav | 20:503cbe360419 | 42 | { |
pvaibhav | 20:503cbe360419 | 43 | delegate = &d; |
pvaibhav | 15:4488660e1a3b | 44 | } |
pvaibhav | 15:4488660e1a3b | 45 | |
uadhikari | 41:731e3cfac19b | 46 | void SensorFusion::startAccelerometer(){ |
pvaibhav | 15:4488660e1a3b | 47 | accel.powerOn(); |
uadhikari | 41:731e3cfac19b | 48 | accel.start(); |
uadhikari | 41:731e3cfac19b | 49 | }; |
uadhikari | 41:731e3cfac19b | 50 | |
uadhikari | 41:731e3cfac19b | 51 | void SensorFusion::startGyrometer(){ |
uadhikari | 41:731e3cfac19b | 52 | gyro.powerOn(); |
uadhikari | 41:731e3cfac19b | 53 | gyro.start(); |
uadhikari | 41:731e3cfac19b | 54 | }; |
uadhikari | 41:731e3cfac19b | 55 | |
uadhikari | 41:731e3cfac19b | 56 | bool SensorFusion::startMagnetometer(){ |
pvaibhav | 15:4488660e1a3b | 57 | magneto.powerOn(); |
uadhikari | 41:731e3cfac19b | 58 | if (magneto.performSelfTest() == false){ |
uadhikari | 41:731e3cfac19b | 59 | //Should it be left powered on |
pvaibhav | 15:4488660e1a3b | 60 | return false; |
pvaibhav | 15:4488660e1a3b | 61 | } |
uadhikari | 41:731e3cfac19b | 62 | magneto.start(); |
uadhikari | 41:731e3cfac19b | 63 | return true; |
uadhikari | 41:731e3cfac19b | 64 | |
uadhikari | 41:731e3cfac19b | 65 | }; |
pvaibhav | 15:4488660e1a3b | 66 | |
uadhikari | 41:731e3cfac19b | 67 | void SensorFusion::stopAccelerometer(){ |
uadhikari | 41:731e3cfac19b | 68 | accel.stop(); |
uadhikari | 41:731e3cfac19b | 69 | accel.powerOff(); |
uadhikari | 41:731e3cfac19b | 70 | }; |
pvaibhav | 15:4488660e1a3b | 71 | |
uadhikari | 41:731e3cfac19b | 72 | void SensorFusion::stopGyrometer(){ |
pvaibhav | 15:4488660e1a3b | 73 | gyro.stop(); |
uadhikari | 41:731e3cfac19b | 74 | gyro.powerOff(); |
uadhikari | 41:731e3cfac19b | 75 | }; |
uadhikari | 41:731e3cfac19b | 76 | |
uadhikari | 41:731e3cfac19b | 77 | void SensorFusion::stopMagnetometer(){ |
pvaibhav | 15:4488660e1a3b | 78 | magneto.stop(); |
uadhikari | 41:731e3cfac19b | 79 | magneto.powerOff(); |
uadhikari | 41:731e3cfac19b | 80 | }; |
pvaibhav | 15:4488660e1a3b | 81 | |
pvaibhav | 15:4488660e1a3b | 82 | static float const deg_to_radian = 0.0174532925f; |
pvaibhav | 15:4488660e1a3b | 83 | |
pvaibhav | 34:01dec68de3ed | 84 | void SensorFusion::getMagnetometerCalibration(Vector3 &min, Vector3 &max) |
pvaibhav | 34:01dec68de3ed | 85 | { |
pvaibhav | 34:01dec68de3ed | 86 | magneto.getCalibration(min, max); |
pvaibhav | 15:4488660e1a3b | 87 | } |
pvaibhav | 15:4488660e1a3b | 88 | |
uadhikari | 41:731e3cfac19b | 89 | /* NineAxesSensor*/ |
pvaibhav | 35:fb6e4601adf3 | 90 | |
uadhikari | 41:731e3cfac19b | 91 | NineAxesSensor::NineAxesSensor(I2C &i2c) : SensorFusion(i2c){} |
pvaibhav | 35:fb6e4601adf3 | 92 | |
uadhikari | 41:731e3cfac19b | 93 | bool NineAxesSensor::start(){ |
uadhikari | 41:731e3cfac19b | 94 | startAccelerometer(); |
uadhikari | 41:731e3cfac19b | 95 | |
uadhikari | 41:731e3cfac19b | 96 | bool magnetoMeterSelfTestResult = startMagnetometer(); |
uadhikari | 41:731e3cfac19b | 97 | if( magnetoMeterSelfTestResult == false){ |
uadhikari | 41:731e3cfac19b | 98 | return false; |
uadhikari | 41:731e3cfac19b | 99 | } |
uadhikari | 41:731e3cfac19b | 100 | |
uadhikari | 41:731e3cfac19b | 101 | //Since everything is synced to gyro interrupt, start it last |
uadhikari | 41:731e3cfac19b | 102 | gyro.setDelegate(*this); |
uadhikari | 41:731e3cfac19b | 103 | startGyrometer(); |
uadhikari | 41:731e3cfac19b | 104 | return true; |
uadhikari | 41:731e3cfac19b | 105 | }; |
pvaibhav | 35:fb6e4601adf3 | 106 | |
uadhikari | 41:731e3cfac19b | 107 | void NineAxesSensor::stop(){ |
uadhikari | 41:731e3cfac19b | 108 | stopAccelerometer(); |
uadhikari | 41:731e3cfac19b | 109 | stopMagnetometer(); |
uadhikari | 41:731e3cfac19b | 110 | stopGyrometer(); |
pvaibhav | 35:fb6e4601adf3 | 111 | } |
pvaibhav | 35:fb6e4601adf3 | 112 | |
uadhikari | 41:731e3cfac19b | 113 | void NineAxesSensor::updateFilter(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz){ |
uadhikari | 41:731e3cfac19b | 114 | float q1 = q.w, |
uadhikari | 41:731e3cfac19b | 115 | q2 = q.v.x, |
uadhikari | 41:731e3cfac19b | 116 | q3 = q.v.y, |
uadhikari | 41:731e3cfac19b | 117 | q4 = q.v.z; // short name local variable for readability |
pvaibhav | 15:4488660e1a3b | 118 | float norm; |
pvaibhav | 15:4488660e1a3b | 119 | float s1, s2, s3, s4; |
pvaibhav | 15:4488660e1a3b | 120 | |
pvaibhav | 15:4488660e1a3b | 121 | // Auxiliary variables to avoid repeated arithmetic |
pvaibhav | 15:4488660e1a3b | 122 | const float _2q1 = 2.0f * q1; |
pvaibhav | 15:4488660e1a3b | 123 | const float _2q2 = 2.0f * q2; |
pvaibhav | 15:4488660e1a3b | 124 | const float _2q3 = 2.0f * q3; |
pvaibhav | 15:4488660e1a3b | 125 | const float _2q4 = 2.0f * q4; |
pvaibhav | 15:4488660e1a3b | 126 | const float _2q1q3 = 2.0f * q1 * q3; |
pvaibhav | 15:4488660e1a3b | 127 | const float _2q3q4 = 2.0f * q3 * q4; |
pvaibhav | 15:4488660e1a3b | 128 | const float q1q1 = q1 * q1; |
pvaibhav | 15:4488660e1a3b | 129 | const float q1q2 = q1 * q2; |
pvaibhav | 15:4488660e1a3b | 130 | const float q1q3 = q1 * q3; |
pvaibhav | 15:4488660e1a3b | 131 | const float q1q4 = q1 * q4; |
pvaibhav | 15:4488660e1a3b | 132 | const float q2q2 = q2 * q2; |
pvaibhav | 15:4488660e1a3b | 133 | const float q2q3 = q2 * q3; |
pvaibhav | 15:4488660e1a3b | 134 | const float q2q4 = q2 * q4; |
pvaibhav | 15:4488660e1a3b | 135 | const float q3q3 = q3 * q3; |
pvaibhav | 15:4488660e1a3b | 136 | const float q3q4 = q3 * q4; |
pvaibhav | 15:4488660e1a3b | 137 | const float q4q4 = q4 * q4; |
pvaibhav | 15:4488660e1a3b | 138 | |
pvaibhav | 15:4488660e1a3b | 139 | // Normalise accelerometer measurement |
pvaibhav | 15:4488660e1a3b | 140 | norm = sqrt(ax * ax + ay * ay + az * az); |
pvaibhav | 15:4488660e1a3b | 141 | if (norm == 0.0f) return; // handle NaN |
pvaibhav | 15:4488660e1a3b | 142 | norm = 1.0f/norm; |
pvaibhav | 15:4488660e1a3b | 143 | ax *= norm; |
pvaibhav | 15:4488660e1a3b | 144 | ay *= norm; |
pvaibhav | 15:4488660e1a3b | 145 | az *= norm; |
pvaibhav | 15:4488660e1a3b | 146 | |
pvaibhav | 15:4488660e1a3b | 147 | // Normalise magnetometer measurement |
pvaibhav | 15:4488660e1a3b | 148 | norm = sqrt(mx * mx + my * my + mz * mz); |
pvaibhav | 15:4488660e1a3b | 149 | if (norm == 0.0f) return; // handle NaN |
pvaibhav | 15:4488660e1a3b | 150 | norm = 1.0f/norm; |
pvaibhav | 15:4488660e1a3b | 151 | mx *= norm; |
pvaibhav | 15:4488660e1a3b | 152 | my *= norm; |
pvaibhav | 15:4488660e1a3b | 153 | mz *= norm; |
pvaibhav | 15:4488660e1a3b | 154 | |
pvaibhav | 15:4488660e1a3b | 155 | // Reference direction of Earth's magnetic field |
pvaibhav | 15:4488660e1a3b | 156 | const float _2q1mx = 2.0f * q1 * mx; |
pvaibhav | 15:4488660e1a3b | 157 | const float _2q1my = 2.0f * q1 * my; |
pvaibhav | 15:4488660e1a3b | 158 | const float _2q1mz = 2.0f * q1 * mz; |
pvaibhav | 15:4488660e1a3b | 159 | const float _2q2mx = 2.0f * q2 * mx; |
pvaibhav | 15:4488660e1a3b | 160 | const float hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4; |
pvaibhav | 15:4488660e1a3b | 161 | const float hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4; |
pvaibhav | 15:4488660e1a3b | 162 | const float _2bx = sqrt(hx * hx + hy * hy); |
pvaibhav | 15:4488660e1a3b | 163 | const float _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4; |
pvaibhav | 15:4488660e1a3b | 164 | const float _4bx = 2.0f * _2bx; |
pvaibhav | 15:4488660e1a3b | 165 | const float _4bz = 2.0f * _2bz; |
pvaibhav | 15:4488660e1a3b | 166 | |
pvaibhav | 15:4488660e1a3b | 167 | // Gradient decent algorithm corrective step |
pvaibhav | 15:4488660e1a3b | 168 | s1 = -_2q3 * (2.0f * q2q4 - _2q1q3 - ax) + _2q2 * (2.0f * q1q2 + _2q3q4 - ay) - _2bz * q3 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q4 + _2bz * q2) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q3 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); |
pvaibhav | 15:4488660e1a3b | 169 | s2 = _2q4 * (2.0f * q2q4 - _2q1q3 - ax) + _2q1 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q2 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + _2bz * q4 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q3 + _2bz * q1) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q4 - _4bz * q2) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); |
pvaibhav | 15:4488660e1a3b | 170 | s3 = -_2q1 * (2.0f * q2q4 - _2q1q3 - ax) + _2q4 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q3 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + (-_4bx * q3 - _2bz * q1) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q2 + _2bz * q4) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q1 - _4bz * q3) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); |
pvaibhav | 15:4488660e1a3b | 171 | s4 = _2q2 * (2.0f * q2q4 - _2q1q3 - ax) + _2q3 * (2.0f * q1q2 + _2q3q4 - ay) + (-_4bx * q4 + _2bz * q2) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q1 + _2bz * q3) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q2 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); |
pvaibhav | 15:4488660e1a3b | 172 | norm = sqrt(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4); // normalise step magnitude |
pvaibhav | 15:4488660e1a3b | 173 | norm = 1.0f/norm; |
pvaibhav | 15:4488660e1a3b | 174 | s1 *= norm; |
pvaibhav | 15:4488660e1a3b | 175 | s2 *= norm; |
pvaibhav | 15:4488660e1a3b | 176 | s3 *= norm; |
pvaibhav | 15:4488660e1a3b | 177 | s4 *= norm; |
pvaibhav | 15:4488660e1a3b | 178 | |
pvaibhav | 15:4488660e1a3b | 179 | // Compute rate of change of quaternion |
pvaibhav | 15:4488660e1a3b | 180 | const float qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1; |
pvaibhav | 15:4488660e1a3b | 181 | const float qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2; |
pvaibhav | 15:4488660e1a3b | 182 | const float qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3; |
pvaibhav | 15:4488660e1a3b | 183 | const float qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4; |
pvaibhav | 15:4488660e1a3b | 184 | |
pvaibhav | 15:4488660e1a3b | 185 | // Integrate to yield quaternion |
pvaibhav | 15:4488660e1a3b | 186 | q1 += qDot1 * deltat; |
pvaibhav | 15:4488660e1a3b | 187 | q2 += qDot2 * deltat; |
pvaibhav | 15:4488660e1a3b | 188 | q3 += qDot3 * deltat; |
pvaibhav | 15:4488660e1a3b | 189 | q4 += qDot4 * deltat; |
pvaibhav | 15:4488660e1a3b | 190 | norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion |
pvaibhav | 15:4488660e1a3b | 191 | norm = 1.0f/norm; |
pvaibhav | 15:4488660e1a3b | 192 | q.w = q1 * norm; |
pvaibhav | 15:4488660e1a3b | 193 | q.v.x = q2 * norm; |
pvaibhav | 15:4488660e1a3b | 194 | q.v.y = q3 * norm; |
uadhikari | 41:731e3cfac19b | 195 | q.v.z = q4 * norm; |
uadhikari | 41:731e3cfac19b | 196 | } |
uadhikari | 41:731e3cfac19b | 197 | |
uadhikari | 41:731e3cfac19b | 198 | void NineAxesSensor::sensorUpdate(Vector3 gyro_degrees){ |
uadhikari | 41:731e3cfac19b | 199 | Vector3 const gyro_reading = gyro_degrees * deg_to_radian; |
uadhikari | 41:731e3cfac19b | 200 | Vector3 const accel_reading = accel.read(); |
uadhikari | 41:731e3cfac19b | 201 | Vector3 const magneto_reading = magneto.read(); |
uadhikari | 41:731e3cfac19b | 202 | |
uadhikari | 41:731e3cfac19b | 203 | updateFilter( accel_reading.x, accel_reading.y, accel_reading.z, |
uadhikari | 41:731e3cfac19b | 204 | gyro_reading.x, gyro_reading.y, gyro_reading.z, |
uadhikari | 41:731e3cfac19b | 205 | magneto_reading.x, magneto_reading.y, magneto_reading.z); |
uadhikari | 41:731e3cfac19b | 206 | |
uadhikari | 41:731e3cfac19b | 207 | delegate->sensorTick(deltat, q.getEulerAngles(), accel_reading, magneto_reading, gyro_degrees, q); |
uadhikari | 41:731e3cfac19b | 208 | } |
uadhikari | 41:731e3cfac19b | 209 | |
uadhikari | 41:731e3cfac19b | 210 | /* SixAxesSensor */ |
uadhikari | 41:731e3cfac19b | 211 | |
uadhikari | 41:731e3cfac19b | 212 | SixAxesSensor::SixAxesSensor(I2C &i2c) : SensorFusion(i2c){} |
uadhikari | 41:731e3cfac19b | 213 | |
uadhikari | 41:731e3cfac19b | 214 | bool SixAxesSensor::start(){ |
uadhikari | 41:731e3cfac19b | 215 | startAccelerometer(); |
uadhikari | 41:731e3cfac19b | 216 | startGyrometer(); |
uadhikari | 41:731e3cfac19b | 217 | gyro.setDelegate(*this); |
uadhikari | 41:731e3cfac19b | 218 | return true; |
uadhikari | 41:731e3cfac19b | 219 | }; |
uadhikari | 41:731e3cfac19b | 220 | |
uadhikari | 41:731e3cfac19b | 221 | void SixAxesSensor::stop(){ |
uadhikari | 41:731e3cfac19b | 222 | stopAccelerometer(); |
uadhikari | 41:731e3cfac19b | 223 | stopGyrometer(); |
pvaibhav | 15:4488660e1a3b | 224 | } |
uadhikari | 41:731e3cfac19b | 225 | |
uadhikari | 41:731e3cfac19b | 226 | void SixAxesSensor::updateFilter(float ax, float ay, float az, float gx, float gy, float gz){ |
uadhikari | 41:731e3cfac19b | 227 | float q0 = q.w, |
uadhikari | 41:731e3cfac19b | 228 | q1 = q.v.x, |
uadhikari | 41:731e3cfac19b | 229 | q2 = q.v.y, |
uadhikari | 41:731e3cfac19b | 230 | q3 = q.v.z; // short name local variable for readability |
uadhikari | 41:731e3cfac19b | 231 | |
uadhikari | 41:731e3cfac19b | 232 | float recipNorm; |
uadhikari | 41:731e3cfac19b | 233 | float s0, s1, s2, s3; |
uadhikari | 41:731e3cfac19b | 234 | float qDot1, qDot2, qDot3, qDot4; |
uadhikari | 41:731e3cfac19b | 235 | float _2q0, _2q1, _2q2, _2q3, _4q0, _4q1, _4q2 ,_8q1, _8q2, q0q0, q1q1, q2q2, q3q3; |
uadhikari | 41:731e3cfac19b | 236 | |
uadhikari | 41:731e3cfac19b | 237 | // Rate of change of quaternion from gyroscope |
uadhikari | 41:731e3cfac19b | 238 | qDot1 = 0.5 * (-q1 * gx - q2 * gy - q3 * gz); |
uadhikari | 41:731e3cfac19b | 239 | qDot2 = 0.5 * (q0 * gx + q2 * gz - q3 * gy); |
uadhikari | 41:731e3cfac19b | 240 | qDot3 = 0.5 * (q0 * gy - q1 * gz + q3 * gx); |
uadhikari | 41:731e3cfac19b | 241 | qDot4 = 0.5 * (q0 * gz + q1 * gy - q2 * gx); |
uadhikari | 41:731e3cfac19b | 242 | |
uadhikari | 41:731e3cfac19b | 243 | // Compute feedback only if accelerometer measurement valid (avoids NaN in accelerometer normalisation) |
uadhikari | 41:731e3cfac19b | 244 | if(!((ax == 0.0) && (ay == 0.0) && (az == 0.0))) { |
uadhikari | 41:731e3cfac19b | 245 | |
uadhikari | 41:731e3cfac19b | 246 | // Normalise accelerometer measurement |
uadhikari | 41:731e3cfac19b | 247 | recipNorm = 1.0 / sqrt(ax * ax + ay * ay + az * az); |
uadhikari | 41:731e3cfac19b | 248 | ax *= recipNorm; |
uadhikari | 41:731e3cfac19b | 249 | ay *= recipNorm; |
uadhikari | 41:731e3cfac19b | 250 | az *= recipNorm; |
uadhikari | 41:731e3cfac19b | 251 | |
uadhikari | 41:731e3cfac19b | 252 | // Auxiliary variables to avoid repeated arithmetic |
uadhikari | 41:731e3cfac19b | 253 | _2q0 = 2.0 * q0; |
uadhikari | 41:731e3cfac19b | 254 | _2q1 = 2.0 * q1; |
uadhikari | 41:731e3cfac19b | 255 | _2q2 = 2.0 * q2; |
uadhikari | 41:731e3cfac19b | 256 | _2q3 = 2.0 * q3; |
uadhikari | 41:731e3cfac19b | 257 | _4q0 = 4.0 * q0; |
uadhikari | 41:731e3cfac19b | 258 | _4q1 = 4.0 * q1; |
uadhikari | 41:731e3cfac19b | 259 | _4q2 = 4.0 * q2; |
uadhikari | 41:731e3cfac19b | 260 | _8q1 = 8.0 * q1; |
uadhikari | 41:731e3cfac19b | 261 | _8q2 = 8.0 * q2; |
uadhikari | 41:731e3cfac19b | 262 | q0q0 = q0 * q0; |
uadhikari | 41:731e3cfac19b | 263 | q1q1 = q1 * q1; |
uadhikari | 41:731e3cfac19b | 264 | q2q2 = q2 * q2; |
uadhikari | 41:731e3cfac19b | 265 | q3q3 = q3 * q3; |
uadhikari | 41:731e3cfac19b | 266 | |
uadhikari | 41:731e3cfac19b | 267 | // Gradient decent algorithm corrective step |
uadhikari | 41:731e3cfac19b | 268 | s0 = _4q0 * q2q2 + _2q2 * ax + _4q0 * q1q1 - _2q1 * ay; |
uadhikari | 41:731e3cfac19b | 269 | s1 = _4q1 * q3q3 - _2q3 * ax + 4.0 * q0q0 * q1 - _2q0 * ay - _4q1 + _8q1 * q1q1 + _8q1 * q2q2 + _4q1 * az; |
uadhikari | 41:731e3cfac19b | 270 | s2 = 4.0 * q0q0 * q2 + _2q0 * ax + _4q2 * q3q3 - _2q3 * ay - _4q2 + _8q2 * q1q1 + _8q2 * q2q2 + _4q2 * az; |
uadhikari | 41:731e3cfac19b | 271 | s3 = 4.0 * q1q1 * q3 - _2q1 * ax + 4.0 * q2q2 * q3 - _2q2 * ay; |
uadhikari | 41:731e3cfac19b | 272 | recipNorm = 1.0 / sqrt(s0 * s0 + s1 * s1 + s2 * s2 + s3 * s3); // normalise step magnitude |
uadhikari | 41:731e3cfac19b | 273 | s0 *= recipNorm; |
uadhikari | 41:731e3cfac19b | 274 | s1 *= recipNorm; |
uadhikari | 41:731e3cfac19b | 275 | s2 *= recipNorm; |
uadhikari | 41:731e3cfac19b | 276 | s3 *= recipNorm; |
uadhikari | 41:731e3cfac19b | 277 | |
uadhikari | 41:731e3cfac19b | 278 | // Apply feedback step |
uadhikari | 41:731e3cfac19b | 279 | qDot1 -= beta * s0; |
uadhikari | 41:731e3cfac19b | 280 | qDot2 -= beta * s1; |
uadhikari | 41:731e3cfac19b | 281 | qDot3 -= beta * s2; |
uadhikari | 41:731e3cfac19b | 282 | qDot4 -= beta * s3; |
uadhikari | 41:731e3cfac19b | 283 | } |
uadhikari | 41:731e3cfac19b | 284 | |
uadhikari | 41:731e3cfac19b | 285 | // Integrate rate of change of quaternion to yield quaternion |
uadhikari | 41:731e3cfac19b | 286 | q0 += qDot1 * deltat; |
uadhikari | 41:731e3cfac19b | 287 | q1 += qDot2 * deltat; |
uadhikari | 41:731e3cfac19b | 288 | q2 += qDot3 * deltat; |
uadhikari | 41:731e3cfac19b | 289 | q3 += qDot4 * deltat; |
uadhikari | 41:731e3cfac19b | 290 | |
uadhikari | 41:731e3cfac19b | 291 | // Normalise quaternion |
uadhikari | 41:731e3cfac19b | 292 | recipNorm = 1.0 / sqrt(q0 * q0 + q1 * q1 + q2 * q2 + q3 * q3); |
uadhikari | 41:731e3cfac19b | 293 | q0 *= recipNorm; |
uadhikari | 41:731e3cfac19b | 294 | q1 *= recipNorm; |
uadhikari | 41:731e3cfac19b | 295 | q2 *= recipNorm; |
uadhikari | 41:731e3cfac19b | 296 | q3 *= recipNorm; |
uadhikari | 41:731e3cfac19b | 297 | |
uadhikari | 41:731e3cfac19b | 298 | // return |
uadhikari | 41:731e3cfac19b | 299 | q.w = q0; |
uadhikari | 41:731e3cfac19b | 300 | q.v.x = q1; |
uadhikari | 41:731e3cfac19b | 301 | q.v.y = q2; |
uadhikari | 41:731e3cfac19b | 302 | q.v.z = q3; |
uadhikari | 41:731e3cfac19b | 303 | } |
uadhikari | 41:731e3cfac19b | 304 | |
uadhikari | 41:731e3cfac19b | 305 | void SixAxesSensor::sensorUpdate(Vector3 gyro_degrees){ |
uadhikari | 41:731e3cfac19b | 306 | Vector3 const gyro_reading = gyro_degrees * deg_to_radian; |
uadhikari | 41:731e3cfac19b | 307 | Vector3 const accel_reading = accel.read(); |
uadhikari | 41:731e3cfac19b | 308 | Vector3 const magneto_reading(0, 0, 0); |
uadhikari | 41:731e3cfac19b | 309 | |
uadhikari | 41:731e3cfac19b | 310 | updateFilter( accel_reading.x, accel_reading.y, accel_reading.z, |
uadhikari | 41:731e3cfac19b | 311 | gyro_reading.x, gyro_reading.y, gyro_reading.z); |
uadhikari | 41:731e3cfac19b | 312 | |
uadhikari | 41:731e3cfac19b | 313 | delegate->sensorTick(deltat, q.getEulerAngles(), accel_reading, magneto_reading, gyro_degrees, q); |
uadhikari | 41:731e3cfac19b | 314 | } |
uadhikari | 41:731e3cfac19b | 315 | |
uadhikari | 41:731e3cfac19b | 316 | bool SensorFusion::start(){ |
uadhikari | 41:731e3cfac19b | 317 | return false; |
uadhikari | 41:731e3cfac19b | 318 | } |
uadhikari | 41:731e3cfac19b | 319 | |
uadhikari | 41:731e3cfac19b | 320 | void SensorFusion::stop(){ |
uadhikari | 41:731e3cfac19b | 321 | |
uadhikari | 41:731e3cfac19b | 322 | } |
uadhikari | 41:731e3cfac19b | 323 | |
uadhikari | 41:731e3cfac19b | 324 | void SensorFusion::sensorUpdate(Vector3 gyro_degrees){ |
uadhikari | 41:731e3cfac19b | 325 | |
uadhikari | 41:731e3cfac19b | 326 | } |
uadhikari | 41:731e3cfac19b | 327 | |
uadhikari | 41:731e3cfac19b | 328 | |
uadhikari | 41:731e3cfac19b | 329 | |
uadhikari | 41:731e3cfac19b | 330 | |
uadhikari | 41:731e3cfac19b | 331 |