Class of MPU9250
Dependencies: AHRS_fillter mbed
Fork of MPU9250AHRS by
AHRS.cpp@6:5665d427bceb, 2016-01-20 (annotated)
- Committer:
- icyzkungz
- Date:
- Wed Jan 20 02:34:07 2016 +0000
- Revision:
- 6:5665d427bceb
- Child:
- 7:3e74239e3778
MPU9250-OOP
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
icyzkungz | 6:5665d427bceb | 1 | #include "AHRS.h" |
icyzkungz | 6:5665d427bceb | 2 | |
icyzkungz | 6:5665d427bceb | 3 | #define Kp 5.1f * 5.0f // these are the free parameters in the Mahony filter and fusion scheme, Kp for proportional feedback, Ki for integral |
icyzkungz | 6:5665d427bceb | 4 | #define Ki 1.0f |
icyzkungz | 6:5665d427bceb | 5 | |
icyzkungz | 6:5665d427bceb | 6 | /*AHRS::AHRS(PinName sda, PinName scl, PinName tx, PinName rx, int address):MPU9250(sda,scl,tx,rx,address) |
icyzkungz | 6:5665d427bceb | 7 | { |
icyzkungz | 6:5665d427bceb | 8 | for(int i=0; i<=3; i++) { |
icyzkungz | 6:5665d427bceb | 9 | eInt[i] = 0; |
icyzkungz | 6:5665d427bceb | 10 | q[i] = 0; // vector to hold quaternion |
icyzkungz | 6:5665d427bceb | 11 | } |
icyzkungz | 6:5665d427bceb | 12 | |
icyzkungz | 6:5665d427bceb | 13 | q[0] = 1.0f; |
icyzkungz | 6:5665d427bceb | 14 | |
icyzkungz | 6:5665d427bceb | 15 | PI = 3.14159265358979323846f; |
icyzkungz | 6:5665d427bceb | 16 | GyroMeasError = PI * (60.0f / 180.0f); // gyroscope measurement error in rads/s (start at 60 deg/s), then reduce after ~10 s to 3 |
icyzkungz | 6:5665d427bceb | 17 | beta = sqrt(3.0f / 4.0f) * GyroMeasError; // compute beta |
icyzkungz | 6:5665d427bceb | 18 | GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s) |
icyzkungz | 6:5665d427bceb | 19 | zeta = sqrt(3.0f / 4.0f) * GyroMeasDrift; // compute zeta, the other free parameter in the Madgwick scheme usually set to a small or zero value |
icyzkungz | 6:5665d427bceb | 20 | }*/ |
icyzkungz | 6:5665d427bceb | 21 | |
icyzkungz | 6:5665d427bceb | 22 | /*void AHRS::MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz, float deltat) |
icyzkungz | 6:5665d427bceb | 23 | { |
icyzkungz | 6:5665d427bceb | 24 | float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability |
icyzkungz | 6:5665d427bceb | 25 | float norm; |
icyzkungz | 6:5665d427bceb | 26 | float hx, hy, _2bx, _2bz; |
icyzkungz | 6:5665d427bceb | 27 | float s1, s2, s3, s4; |
icyzkungz | 6:5665d427bceb | 28 | float qDot1, qDot2, qDot3, qDot4; |
icyzkungz | 6:5665d427bceb | 29 | |
icyzkungz | 6:5665d427bceb | 30 | // Auxiliary variables to avoid repeated arithmetic |
icyzkungz | 6:5665d427bceb | 31 | float _2q1mx; |
icyzkungz | 6:5665d427bceb | 32 | float _2q1my; |
icyzkungz | 6:5665d427bceb | 33 | float _2q1mz; |
icyzkungz | 6:5665d427bceb | 34 | float _2q2mx; |
icyzkungz | 6:5665d427bceb | 35 | float _4bx; |
icyzkungz | 6:5665d427bceb | 36 | float _4bz; |
icyzkungz | 6:5665d427bceb | 37 | float _2q1 = 2.0f * q1; |
icyzkungz | 6:5665d427bceb | 38 | float _2q2 = 2.0f * q2; |
icyzkungz | 6:5665d427bceb | 39 | float _2q3 = 2.0f * q3; |
icyzkungz | 6:5665d427bceb | 40 | float _2q4 = 2.0f * q4; |
icyzkungz | 6:5665d427bceb | 41 | float _2q1q3 = 2.0f * q1 * q3; |
icyzkungz | 6:5665d427bceb | 42 | float _2q3q4 = 2.0f * q3 * q4; |
icyzkungz | 6:5665d427bceb | 43 | float q1q1 = q1 * q1; |
icyzkungz | 6:5665d427bceb | 44 | float q1q2 = q1 * q2; |
icyzkungz | 6:5665d427bceb | 45 | float q1q3 = q1 * q3; |
icyzkungz | 6:5665d427bceb | 46 | float q1q4 = q1 * q4; |
icyzkungz | 6:5665d427bceb | 47 | float q2q2 = q2 * q2; |
icyzkungz | 6:5665d427bceb | 48 | float q2q3 = q2 * q3; |
icyzkungz | 6:5665d427bceb | 49 | float q2q4 = q2 * q4; |
icyzkungz | 6:5665d427bceb | 50 | float q3q3 = q3 * q3; |
icyzkungz | 6:5665d427bceb | 51 | float q3q4 = q3 * q4; |
icyzkungz | 6:5665d427bceb | 52 | float q4q4 = q4 * q4; |
icyzkungz | 6:5665d427bceb | 53 | |
icyzkungz | 6:5665d427bceb | 54 | // Normalise accelerometer measurement |
icyzkungz | 6:5665d427bceb | 55 | norm = sqrt(ax * ax + ay * ay + az * az); |
icyzkungz | 6:5665d427bceb | 56 | if (norm == 0.0f) return; // handle NaN |
icyzkungz | 6:5665d427bceb | 57 | norm = 1.0f/norm; |
icyzkungz | 6:5665d427bceb | 58 | ax *= norm; |
icyzkungz | 6:5665d427bceb | 59 | ay *= norm; |
icyzkungz | 6:5665d427bceb | 60 | az *= norm; |
icyzkungz | 6:5665d427bceb | 61 | |
icyzkungz | 6:5665d427bceb | 62 | // Normalise magnetometer measurement |
icyzkungz | 6:5665d427bceb | 63 | norm = sqrt(mx * mx + my * my + mz * mz); |
icyzkungz | 6:5665d427bceb | 64 | if (norm == 0.0f) return; // handle NaN |
icyzkungz | 6:5665d427bceb | 65 | norm = 1.0f/norm; |
icyzkungz | 6:5665d427bceb | 66 | mx *= norm; |
icyzkungz | 6:5665d427bceb | 67 | my *= norm; |
icyzkungz | 6:5665d427bceb | 68 | mz *= norm; |
icyzkungz | 6:5665d427bceb | 69 | |
icyzkungz | 6:5665d427bceb | 70 | // Reference direction of Earth's magnetic field |
icyzkungz | 6:5665d427bceb | 71 | _2q1mx = 2.0f * q1 * mx; |
icyzkungz | 6:5665d427bceb | 72 | _2q1my = 2.0f * q1 * my; |
icyzkungz | 6:5665d427bceb | 73 | _2q1mz = 2.0f * q1 * mz; |
icyzkungz | 6:5665d427bceb | 74 | _2q2mx = 2.0f * q2 * mx; |
icyzkungz | 6:5665d427bceb | 75 | hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4; |
icyzkungz | 6:5665d427bceb | 76 | hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4; |
icyzkungz | 6:5665d427bceb | 77 | _2bx = sqrt(hx * hx + hy * hy); |
icyzkungz | 6:5665d427bceb | 78 | _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4; |
icyzkungz | 6:5665d427bceb | 79 | _4bx = 2.0f * _2bx; |
icyzkungz | 6:5665d427bceb | 80 | _4bz = 2.0f * _2bz; |
icyzkungz | 6:5665d427bceb | 81 | |
icyzkungz | 6:5665d427bceb | 82 | // Gradient decent algorithm corrective step |
icyzkungz | 6:5665d427bceb | 83 | 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); |
icyzkungz | 6:5665d427bceb | 84 | 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); |
icyzkungz | 6:5665d427bceb | 85 | 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); |
icyzkungz | 6:5665d427bceb | 86 | 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); |
icyzkungz | 6:5665d427bceb | 87 | norm = sqrt(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4); // normalise step magnitude |
icyzkungz | 6:5665d427bceb | 88 | norm = 1.0f/norm; |
icyzkungz | 6:5665d427bceb | 89 | s1 *= norm; |
icyzkungz | 6:5665d427bceb | 90 | s2 *= norm; |
icyzkungz | 6:5665d427bceb | 91 | s3 *= norm; |
icyzkungz | 6:5665d427bceb | 92 | s4 *= norm; |
icyzkungz | 6:5665d427bceb | 93 | |
icyzkungz | 6:5665d427bceb | 94 | // Compute rate of change of quaternion |
icyzkungz | 6:5665d427bceb | 95 | qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1; |
icyzkungz | 6:5665d427bceb | 96 | qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2; |
icyzkungz | 6:5665d427bceb | 97 | qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3; |
icyzkungz | 6:5665d427bceb | 98 | qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4; |
icyzkungz | 6:5665d427bceb | 99 | |
icyzkungz | 6:5665d427bceb | 100 | // Integrate to yield quaternion |
icyzkungz | 6:5665d427bceb | 101 | q1 += qDot1 * deltat; |
icyzkungz | 6:5665d427bceb | 102 | q2 += qDot2 * deltat; |
icyzkungz | 6:5665d427bceb | 103 | q3 += qDot3 * deltat; |
icyzkungz | 6:5665d427bceb | 104 | q4 += qDot4 * deltat; |
icyzkungz | 6:5665d427bceb | 105 | norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion |
icyzkungz | 6:5665d427bceb | 106 | norm = 1.0f/norm; |
icyzkungz | 6:5665d427bceb | 107 | q[0] = q1 * norm; |
icyzkungz | 6:5665d427bceb | 108 | q[1] = q2 * norm; |
icyzkungz | 6:5665d427bceb | 109 | q[2] = q3 * norm; |
icyzkungz | 6:5665d427bceb | 110 | q[3] = q4 * norm; |
icyzkungz | 6:5665d427bceb | 111 | |
icyzkungz | 6:5665d427bceb | 112 | yaw = atan2(2.0f * (q[1] * q[2] + q[0] * q[3]), q[0] * q[0] + q[1] * q[1] - q[2] * q[2] - q[3] * q[3]); |
icyzkungz | 6:5665d427bceb | 113 | pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2])); |
icyzkungz | 6:5665d427bceb | 114 | roll = atan2(2.0f * (q[0] * q[1] + q[2] * q[3]), q[0] * q[0] - q[1] * q[1] - q[2] * q[2] + q[3] * q[3]); |
icyzkungz | 6:5665d427bceb | 115 | |
icyzkungz | 6:5665d427bceb | 116 | float Xh = mx*cos(pitch)+my*sin(roll)*sin(pitch)-mz*cos(roll)*sin(pitch); |
icyzkungz | 6:5665d427bceb | 117 | float Yh = my*cos(roll)+mz*sin(roll); |
icyzkungz | 6:5665d427bceb | 118 | |
icyzkungz | 6:5665d427bceb | 119 | float yawmag = atan2(Yh,Xh)+PI; |
icyzkungz | 6:5665d427bceb | 120 | //////test.printf("Xh= %f Yh= %f ",Xh,Yh); |
icyzkungz | 6:5665d427bceb | 121 | //////test.printf("Yaw[mag]= %f\n\r",yawmag*180.0f/PI); |
icyzkungz | 6:5665d427bceb | 122 | //test.printf(",%f",yawmag*180.0f/PI); |
icyzkungz | 6:5665d427bceb | 123 | |
icyzkungz | 6:5665d427bceb | 124 | |
icyzkungz | 6:5665d427bceb | 125 | |
icyzkungz | 6:5665d427bceb | 126 | pitch *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 127 | yaw *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 128 | yaw += 180.0f; // Declination at Danville, California is 13 degrees 48 minutes and 47 seconds on 2014-04-04 |
icyzkungz | 6:5665d427bceb | 129 | roll *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 130 | |
icyzkungz | 6:5665d427bceb | 131 | } |
icyzkungz | 6:5665d427bceb | 132 | |
icyzkungz | 6:5665d427bceb | 133 | |
icyzkungz | 6:5665d427bceb | 134 | |
icyzkungz | 6:5665d427bceb | 135 | // Similar to Madgwick scheme but uses proportional and integral filtering on the error between estimated reference vectors and |
icyzkungz | 6:5665d427bceb | 136 | // measured ones. |
icyzkungz | 6:5665d427bceb | 137 | void AHRS::MahonyQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz, float deltat) |
icyzkungz | 6:5665d427bceb | 138 | { |
icyzkungz | 6:5665d427bceb | 139 | q1 = q[0]; |
icyzkungz | 6:5665d427bceb | 140 | q2 = q[1]; |
icyzkungz | 6:5665d427bceb | 141 | q3 = q[2]; |
icyzkungz | 6:5665d427bceb | 142 | q4 = q[3]; // short name local variable for readability |
icyzkungz | 6:5665d427bceb | 143 | |
icyzkungz | 6:5665d427bceb | 144 | // Auxiliary variables to avoid repeated arithmetic |
icyzkungz | 6:5665d427bceb | 145 | q1q1 = q1 * q1; |
icyzkungz | 6:5665d427bceb | 146 | q1q2 = q1 * q2; |
icyzkungz | 6:5665d427bceb | 147 | q1q3 = q1 * q3; |
icyzkungz | 6:5665d427bceb | 148 | q1q4 = q1 * q4; |
icyzkungz | 6:5665d427bceb | 149 | q2q2 = q2 * q2; |
icyzkungz | 6:5665d427bceb | 150 | q2q3 = q2 * q3; |
icyzkungz | 6:5665d427bceb | 151 | q2q4 = q2 * q4; |
icyzkungz | 6:5665d427bceb | 152 | q3q3 = q3 * q3; |
icyzkungz | 6:5665d427bceb | 153 | q3q4 = q3 * q4; |
icyzkungz | 6:5665d427bceb | 154 | q4q4 = q4 * q4; |
icyzkungz | 6:5665d427bceb | 155 | |
icyzkungz | 6:5665d427bceb | 156 | // Normalise accelerometer measurement |
icyzkungz | 6:5665d427bceb | 157 | norm = sqrt(ax * ax + ay * ay + az * az); |
icyzkungz | 6:5665d427bceb | 158 | if (norm == 0.0f) return; // handle NaN |
icyzkungz | 6:5665d427bceb | 159 | norm = 1.0f / norm; // use reciprocal for division |
icyzkungz | 6:5665d427bceb | 160 | ax *= norm; |
icyzkungz | 6:5665d427bceb | 161 | ay *= norm; |
icyzkungz | 6:5665d427bceb | 162 | az *= norm; |
icyzkungz | 6:5665d427bceb | 163 | |
icyzkungz | 6:5665d427bceb | 164 | // Normalise magnetometer measurement |
icyzkungz | 6:5665d427bceb | 165 | norm = sqrt(mx * mx + my * my + mz * mz); |
icyzkungz | 6:5665d427bceb | 166 | if (norm == 0.0f) return; // handle NaN |
icyzkungz | 6:5665d427bceb | 167 | norm = 1.0f / norm; // use reciprocal for division |
icyzkungz | 6:5665d427bceb | 168 | mx *= norm; |
icyzkungz | 6:5665d427bceb | 169 | my *= norm; |
icyzkungz | 6:5665d427bceb | 170 | mz *= norm; |
icyzkungz | 6:5665d427bceb | 171 | |
icyzkungz | 6:5665d427bceb | 172 | // Reference direction of Earth's magnetic field |
icyzkungz | 6:5665d427bceb | 173 | hx = 2.0f * mx * (0.5f - q3q3 - q4q4) + 2.0f * my * (q2q3 - q1q4) + 2.0f * mz * (q2q4 + q1q3); |
icyzkungz | 6:5665d427bceb | 174 | hy = 2.0f * mx * (q2q3 + q1q4) + 2.0f * my * (0.5f - q2q2 - q4q4) + 2.0f * mz * (q3q4 - q1q2); |
icyzkungz | 6:5665d427bceb | 175 | bx = sqrt((hx * hx) + (hy * hy)); |
icyzkungz | 6:5665d427bceb | 176 | bz = 2.0f * mx * (q2q4 - q1q3) + 2.0f * my * (q3q4 + q1q2) + 2.0f * mz * (0.5f - q2q2 - q3q3); |
icyzkungz | 6:5665d427bceb | 177 | |
icyzkungz | 6:5665d427bceb | 178 | // Estimated direction of gravity and magnetic field |
icyzkungz | 6:5665d427bceb | 179 | vx = 2.0f * (q2q4 - q1q3); |
icyzkungz | 6:5665d427bceb | 180 | vy = 2.0f * (q1q2 + q3q4); |
icyzkungz | 6:5665d427bceb | 181 | vz = q1q1 - q2q2 - q3q3 + q4q4; |
icyzkungz | 6:5665d427bceb | 182 | wx = 2.0f * bx * (0.5f - q3q3 - q4q4) + 2.0f * bz * (q2q4 - q1q3); |
icyzkungz | 6:5665d427bceb | 183 | wy = 2.0f * bx * (q2q3 - q1q4) + 2.0f * bz * (q1q2 + q3q4); |
icyzkungz | 6:5665d427bceb | 184 | wz = 2.0f * bx * (q1q3 + q2q4) + 2.0f * bz * (0.5f - q2q2 - q3q3); |
icyzkungz | 6:5665d427bceb | 185 | |
icyzkungz | 6:5665d427bceb | 186 | // Error is cross product between estimated direction and measured direction of gravity |
icyzkungz | 6:5665d427bceb | 187 | ex = (ay * vz - az * vy) + (my * wz - mz * wy); |
icyzkungz | 6:5665d427bceb | 188 | ey = (az * vx - ax * vz) + (mz * wx - mx * wz); |
icyzkungz | 6:5665d427bceb | 189 | ez = (ax * vy - ay * vx) + (mx * wy - my * wx); |
icyzkungz | 6:5665d427bceb | 190 | if (Ki > 0.0f) { |
icyzkungz | 6:5665d427bceb | 191 | eInt[0] += ex; // accumulate integral error |
icyzkungz | 6:5665d427bceb | 192 | eInt[1] += ey; |
icyzkungz | 6:5665d427bceb | 193 | eInt[2] += ez; |
icyzkungz | 6:5665d427bceb | 194 | } else { |
icyzkungz | 6:5665d427bceb | 195 | eInt[0] = 0.0f; // prevent integral wind up |
icyzkungz | 6:5665d427bceb | 196 | eInt[1] = 0.0f; |
icyzkungz | 6:5665d427bceb | 197 | eInt[2] = 0.0f; |
icyzkungz | 6:5665d427bceb | 198 | } |
icyzkungz | 6:5665d427bceb | 199 | |
icyzkungz | 6:5665d427bceb | 200 | // Apply feedback terms |
icyzkungz | 6:5665d427bceb | 201 | gx = gx + Kp * ex + Ki * eInt[0]; |
icyzkungz | 6:5665d427bceb | 202 | gy = gy + Kp * ey + Ki * eInt[1]; |
icyzkungz | 6:5665d427bceb | 203 | gz = gz + Kp * ez + Ki * eInt[2]; |
icyzkungz | 6:5665d427bceb | 204 | |
icyzkungz | 6:5665d427bceb | 205 | // Integrate rate of change of quaternion |
icyzkungz | 6:5665d427bceb | 206 | pa = q2; |
icyzkungz | 6:5665d427bceb | 207 | pb = q3; |
icyzkungz | 6:5665d427bceb | 208 | pc = q4; |
icyzkungz | 6:5665d427bceb | 209 | q1 = q1 + (-q2 * gx - q3 * gy - q4 * gz) * (0.5f * deltat); |
icyzkungz | 6:5665d427bceb | 210 | q2 = pa + (q1 * gx + pb * gz - pc * gy) * (0.5f * deltat); |
icyzkungz | 6:5665d427bceb | 211 | q3 = pb + (q1 * gy - pa * gz + pc * gx) * (0.5f * deltat); |
icyzkungz | 6:5665d427bceb | 212 | q4 = pc + (q1 * gz + pa * gy - pb * gx) * (0.5f * deltat); |
icyzkungz | 6:5665d427bceb | 213 | |
icyzkungz | 6:5665d427bceb | 214 | // Normalise quaternion |
icyzkungz | 6:5665d427bceb | 215 | norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); |
icyzkungz | 6:5665d427bceb | 216 | norm = 1.0f / norm; |
icyzkungz | 6:5665d427bceb | 217 | q[0] = q1 * norm; |
icyzkungz | 6:5665d427bceb | 218 | q[1] = q2 * norm; |
icyzkungz | 6:5665d427bceb | 219 | q[2] = q3 * norm; |
icyzkungz | 6:5665d427bceb | 220 | q[3] = q4 * norm; |
icyzkungz | 6:5665d427bceb | 221 | |
icyzkungz | 6:5665d427bceb | 222 | yaw = atan2(2.0f * (q[1] * q[2] + q[0] * q[3]), q[0] * q[0] + q[1] * q[1] - q[2] * q[2] - q[3] * q[3]); |
icyzkungz | 6:5665d427bceb | 223 | pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2])); |
icyzkungz | 6:5665d427bceb | 224 | roll = atan2(2.0f * (q[0] * q[1] + q[2] * q[3]), q[0] * q[0] - q[1] * q[1] - q[2] * q[2] + q[3] * q[3]); |
icyzkungz | 6:5665d427bceb | 225 | |
icyzkungz | 6:5665d427bceb | 226 | Xh = mx*cos(pitch)+my*sin(roll)*sin(pitch)-mz*cos(roll)*sin(pitch); |
icyzkungz | 6:5665d427bceb | 227 | Yh = my*cos(roll)+mz*sin(roll); |
icyzkungz | 6:5665d427bceb | 228 | |
icyzkungz | 6:5665d427bceb | 229 | yawmag = atan2(Yh,Xh)+PI; |
icyzkungz | 6:5665d427bceb | 230 | ////////////test.printf("Xh= %f Yh= %f ",Xh,Yh); |
icyzkungz | 6:5665d427bceb | 231 | //////test.printf("Yaw[mag]= %f\n\r",yawmag*180.0f/PI); |
icyzkungz | 6:5665d427bceb | 232 | //test.printf(",%f",yawmag*180.0f/PI); |
icyzkungz | 6:5665d427bceb | 233 | |
icyzkungz | 6:5665d427bceb | 234 | |
icyzkungz | 6:5665d427bceb | 235 | |
icyzkungz | 6:5665d427bceb | 236 | pitch *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 237 | yaw *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 238 | yaw += 180.0f; // Declination at Danville, California is 13 degrees 48 minutes and 47 seconds on 2014-04-04 |
icyzkungz | 6:5665d427bceb | 239 | roll *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 240 | }*/ |
icyzkungz | 6:5665d427bceb | 241 | |
icyzkungz | 6:5665d427bceb | 242 | void AHRS::MadgwickQuaternionUpdate() |
icyzkungz | 6:5665d427bceb | 243 | { |
icyzkungz | 6:5665d427bceb | 244 | float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability |
icyzkungz | 6:5665d427bceb | 245 | float norm; |
icyzkungz | 6:5665d427bceb | 246 | float hx, hy, _2bx, _2bz; |
icyzkungz | 6:5665d427bceb | 247 | float s1, s2, s3, s4; |
icyzkungz | 6:5665d427bceb | 248 | float qDot1, qDot2, qDot3, qDot4; |
icyzkungz | 6:5665d427bceb | 249 | |
icyzkungz | 6:5665d427bceb | 250 | // Auxiliary variables to avoid repeated arithmetic |
icyzkungz | 6:5665d427bceb | 251 | float _2q1mx; |
icyzkungz | 6:5665d427bceb | 252 | float _2q1my; |
icyzkungz | 6:5665d427bceb | 253 | float _2q1mz; |
icyzkungz | 6:5665d427bceb | 254 | float _2q2mx; |
icyzkungz | 6:5665d427bceb | 255 | float _4bx; |
icyzkungz | 6:5665d427bceb | 256 | float _4bz; |
icyzkungz | 6:5665d427bceb | 257 | float _2q1 = 2.0f * q1; |
icyzkungz | 6:5665d427bceb | 258 | float _2q2 = 2.0f * q2; |
icyzkungz | 6:5665d427bceb | 259 | float _2q3 = 2.0f * q3; |
icyzkungz | 6:5665d427bceb | 260 | float _2q4 = 2.0f * q4; |
icyzkungz | 6:5665d427bceb | 261 | float _2q1q3 = 2.0f * q1 * q3; |
icyzkungz | 6:5665d427bceb | 262 | float _2q3q4 = 2.0f * q3 * q4; |
icyzkungz | 6:5665d427bceb | 263 | float q1q1 = q1 * q1; |
icyzkungz | 6:5665d427bceb | 264 | float q1q2 = q1 * q2; |
icyzkungz | 6:5665d427bceb | 265 | float q1q3 = q1 * q3; |
icyzkungz | 6:5665d427bceb | 266 | float q1q4 = q1 * q4; |
icyzkungz | 6:5665d427bceb | 267 | float q2q2 = q2 * q2; |
icyzkungz | 6:5665d427bceb | 268 | float q2q3 = q2 * q3; |
icyzkungz | 6:5665d427bceb | 269 | float q2q4 = q2 * q4; |
icyzkungz | 6:5665d427bceb | 270 | float q3q3 = q3 * q3; |
icyzkungz | 6:5665d427bceb | 271 | float q3q4 = q3 * q4; |
icyzkungz | 6:5665d427bceb | 272 | float q4q4 = q4 * q4; |
icyzkungz | 6:5665d427bceb | 273 | |
icyzkungz | 6:5665d427bceb | 274 | // Normalise accelerometer measurement |
icyzkungz | 6:5665d427bceb | 275 | norm = sqrt(ax * ax + ay * ay + az * az); |
icyzkungz | 6:5665d427bceb | 276 | if (norm == 0.0f) return; // handle NaN |
icyzkungz | 6:5665d427bceb | 277 | norm = 1.0f/norm; |
icyzkungz | 6:5665d427bceb | 278 | ax *= norm; |
icyzkungz | 6:5665d427bceb | 279 | ay *= norm; |
icyzkungz | 6:5665d427bceb | 280 | az *= norm; |
icyzkungz | 6:5665d427bceb | 281 | |
icyzkungz | 6:5665d427bceb | 282 | // Normalise magnetometer measurement |
icyzkungz | 6:5665d427bceb | 283 | norm = sqrt(mx * mx + my * my + mz * mz); |
icyzkungz | 6:5665d427bceb | 284 | if (norm == 0.0f) return; // handle NaN |
icyzkungz | 6:5665d427bceb | 285 | norm = 1.0f/norm; |
icyzkungz | 6:5665d427bceb | 286 | mx *= norm; |
icyzkungz | 6:5665d427bceb | 287 | my *= norm; |
icyzkungz | 6:5665d427bceb | 288 | mz *= norm; |
icyzkungz | 6:5665d427bceb | 289 | |
icyzkungz | 6:5665d427bceb | 290 | // Reference direction of Earth's magnetic field |
icyzkungz | 6:5665d427bceb | 291 | _2q1mx = 2.0f * q1 * mx; |
icyzkungz | 6:5665d427bceb | 292 | _2q1my = 2.0f * q1 * my; |
icyzkungz | 6:5665d427bceb | 293 | _2q1mz = 2.0f * q1 * mz; |
icyzkungz | 6:5665d427bceb | 294 | _2q2mx = 2.0f * q2 * mx; |
icyzkungz | 6:5665d427bceb | 295 | hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4; |
icyzkungz | 6:5665d427bceb | 296 | hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4; |
icyzkungz | 6:5665d427bceb | 297 | _2bx = sqrt(hx * hx + hy * hy); |
icyzkungz | 6:5665d427bceb | 298 | _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4; |
icyzkungz | 6:5665d427bceb | 299 | _4bx = 2.0f * _2bx; |
icyzkungz | 6:5665d427bceb | 300 | _4bz = 2.0f * _2bz; |
icyzkungz | 6:5665d427bceb | 301 | |
icyzkungz | 6:5665d427bceb | 302 | // Gradient decent algorithm corrective step |
icyzkungz | 6:5665d427bceb | 303 | 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); |
icyzkungz | 6:5665d427bceb | 304 | 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); |
icyzkungz | 6:5665d427bceb | 305 | 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); |
icyzkungz | 6:5665d427bceb | 306 | 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); |
icyzkungz | 6:5665d427bceb | 307 | norm = sqrt(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4); // normalise step magnitude |
icyzkungz | 6:5665d427bceb | 308 | norm = 1.0f/norm; |
icyzkungz | 6:5665d427bceb | 309 | s1 *= norm; |
icyzkungz | 6:5665d427bceb | 310 | s2 *= norm; |
icyzkungz | 6:5665d427bceb | 311 | s3 *= norm; |
icyzkungz | 6:5665d427bceb | 312 | s4 *= norm; |
icyzkungz | 6:5665d427bceb | 313 | |
icyzkungz | 6:5665d427bceb | 314 | // Compute rate of change of quaternion |
icyzkungz | 6:5665d427bceb | 315 | qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1; |
icyzkungz | 6:5665d427bceb | 316 | qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2; |
icyzkungz | 6:5665d427bceb | 317 | qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3; |
icyzkungz | 6:5665d427bceb | 318 | qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4; |
icyzkungz | 6:5665d427bceb | 319 | |
icyzkungz | 6:5665d427bceb | 320 | // Integrate to yield quaternion |
icyzkungz | 6:5665d427bceb | 321 | q1 += qDot1 * deltat; |
icyzkungz | 6:5665d427bceb | 322 | q2 += qDot2 * deltat; |
icyzkungz | 6:5665d427bceb | 323 | q3 += qDot3 * deltat; |
icyzkungz | 6:5665d427bceb | 324 | q4 += qDot4 * deltat; |
icyzkungz | 6:5665d427bceb | 325 | norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion |
icyzkungz | 6:5665d427bceb | 326 | norm = 1.0f/norm; |
icyzkungz | 6:5665d427bceb | 327 | q[0] = q1 * norm; |
icyzkungz | 6:5665d427bceb | 328 | q[1] = q2 * norm; |
icyzkungz | 6:5665d427bceb | 329 | q[2] = q3 * norm; |
icyzkungz | 6:5665d427bceb | 330 | q[3] = q4 * norm; |
icyzkungz | 6:5665d427bceb | 331 | |
icyzkungz | 6:5665d427bceb | 332 | yaw = atan2(2.0f * (q[1] * q[2] + q[0] * q[3]), q[0] * q[0] + q[1] * q[1] - q[2] * q[2] - q[3] * q[3]); |
icyzkungz | 6:5665d427bceb | 333 | pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2])); |
icyzkungz | 6:5665d427bceb | 334 | roll = atan2(2.0f * (q[0] * q[1] + q[2] * q[3]), q[0] * q[0] - q[1] * q[1] - q[2] * q[2] + q[3] * q[3]); |
icyzkungz | 6:5665d427bceb | 335 | |
icyzkungz | 6:5665d427bceb | 336 | float Xh = mx*cos(pitch)+my*sin(roll)*sin(pitch)-mz*cos(roll)*sin(pitch); |
icyzkungz | 6:5665d427bceb | 337 | float Yh = my*cos(roll)+mz*sin(roll); |
icyzkungz | 6:5665d427bceb | 338 | |
icyzkungz | 6:5665d427bceb | 339 | float yawmag = atan2(Yh,Xh)+PI; |
icyzkungz | 6:5665d427bceb | 340 | //////test.printf("Xh= %f Yh= %f ",Xh,Yh); |
icyzkungz | 6:5665d427bceb | 341 | //////test.printf("Yaw[mag]= %f\n\r",yawmag*180.0f/PI); |
icyzkungz | 6:5665d427bceb | 342 | //test.printf(",%f",yawmag*180.0f/PI); |
icyzkungz | 6:5665d427bceb | 343 | |
icyzkungz | 6:5665d427bceb | 344 | |
icyzkungz | 6:5665d427bceb | 345 | |
icyzkungz | 6:5665d427bceb | 346 | pitch *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 347 | yaw *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 348 | yaw += 180.0f; // Declination at Danville, California is 13 degrees 48 minutes and 47 seconds on 2014-04-04 |
icyzkungz | 6:5665d427bceb | 349 | roll *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 350 | |
icyzkungz | 6:5665d427bceb | 351 | } |
icyzkungz | 6:5665d427bceb | 352 | |
icyzkungz | 6:5665d427bceb | 353 | |
icyzkungz | 6:5665d427bceb | 354 | |
icyzkungz | 6:5665d427bceb | 355 | // Similar to Madgwick scheme but uses proportional and integral filtering on the error between estimated reference vectors and |
icyzkungz | 6:5665d427bceb | 356 | // measured ones. |
icyzkungz | 6:5665d427bceb | 357 | void AHRS::MahonyQuaternionUpdate() |
icyzkungz | 6:5665d427bceb | 358 | { |
icyzkungz | 6:5665d427bceb | 359 | q1 = q[0]; |
icyzkungz | 6:5665d427bceb | 360 | q2 = q[1]; |
icyzkungz | 6:5665d427bceb | 361 | q3 = q[2]; |
icyzkungz | 6:5665d427bceb | 362 | q4 = q[3]; // short name local variable for readability |
icyzkungz | 6:5665d427bceb | 363 | |
icyzkungz | 6:5665d427bceb | 364 | // Auxiliary variables to avoid repeated arithmetic |
icyzkungz | 6:5665d427bceb | 365 | q1q1 = q1 * q1; |
icyzkungz | 6:5665d427bceb | 366 | q1q2 = q1 * q2; |
icyzkungz | 6:5665d427bceb | 367 | q1q3 = q1 * q3; |
icyzkungz | 6:5665d427bceb | 368 | q1q4 = q1 * q4; |
icyzkungz | 6:5665d427bceb | 369 | q2q2 = q2 * q2; |
icyzkungz | 6:5665d427bceb | 370 | q2q3 = q2 * q3; |
icyzkungz | 6:5665d427bceb | 371 | q2q4 = q2 * q4; |
icyzkungz | 6:5665d427bceb | 372 | q3q3 = q3 * q3; |
icyzkungz | 6:5665d427bceb | 373 | q3q4 = q3 * q4; |
icyzkungz | 6:5665d427bceb | 374 | q4q4 = q4 * q4; |
icyzkungz | 6:5665d427bceb | 375 | |
icyzkungz | 6:5665d427bceb | 376 | // Normalise accelerometer measurement |
icyzkungz | 6:5665d427bceb | 377 | norm = sqrt(ax * ax + ay * ay + az * az); |
icyzkungz | 6:5665d427bceb | 378 | if (norm == 0.0f) return; // handle NaN |
icyzkungz | 6:5665d427bceb | 379 | norm = 1.0f / norm; // use reciprocal for division |
icyzkungz | 6:5665d427bceb | 380 | ax *= norm; |
icyzkungz | 6:5665d427bceb | 381 | ay *= norm; |
icyzkungz | 6:5665d427bceb | 382 | az *= norm; |
icyzkungz | 6:5665d427bceb | 383 | |
icyzkungz | 6:5665d427bceb | 384 | // Normalise magnetometer measurement |
icyzkungz | 6:5665d427bceb | 385 | norm = sqrt(mx * mx + my * my + mz * mz); |
icyzkungz | 6:5665d427bceb | 386 | if (norm == 0.0f) return; // handle NaN |
icyzkungz | 6:5665d427bceb | 387 | norm = 1.0f / norm; // use reciprocal for division |
icyzkungz | 6:5665d427bceb | 388 | mx *= norm; |
icyzkungz | 6:5665d427bceb | 389 | my *= norm; |
icyzkungz | 6:5665d427bceb | 390 | mz *= norm; |
icyzkungz | 6:5665d427bceb | 391 | |
icyzkungz | 6:5665d427bceb | 392 | // Reference direction of Earth's magnetic field |
icyzkungz | 6:5665d427bceb | 393 | hx = 2.0f * mx * (0.5f - q3q3 - q4q4) + 2.0f * my * (q2q3 - q1q4) + 2.0f * mz * (q2q4 + q1q3); |
icyzkungz | 6:5665d427bceb | 394 | hy = 2.0f * mx * (q2q3 + q1q4) + 2.0f * my * (0.5f - q2q2 - q4q4) + 2.0f * mz * (q3q4 - q1q2); |
icyzkungz | 6:5665d427bceb | 395 | bx = sqrt((hx * hx) + (hy * hy)); |
icyzkungz | 6:5665d427bceb | 396 | bz = 2.0f * mx * (q2q4 - q1q3) + 2.0f * my * (q3q4 + q1q2) + 2.0f * mz * (0.5f - q2q2 - q3q3); |
icyzkungz | 6:5665d427bceb | 397 | |
icyzkungz | 6:5665d427bceb | 398 | // Estimated direction of gravity and magnetic field |
icyzkungz | 6:5665d427bceb | 399 | vx = 2.0f * (q2q4 - q1q3); |
icyzkungz | 6:5665d427bceb | 400 | vy = 2.0f * (q1q2 + q3q4); |
icyzkungz | 6:5665d427bceb | 401 | vz = q1q1 - q2q2 - q3q3 + q4q4; |
icyzkungz | 6:5665d427bceb | 402 | wx = 2.0f * bx * (0.5f - q3q3 - q4q4) + 2.0f * bz * (q2q4 - q1q3); |
icyzkungz | 6:5665d427bceb | 403 | wy = 2.0f * bx * (q2q3 - q1q4) + 2.0f * bz * (q1q2 + q3q4); |
icyzkungz | 6:5665d427bceb | 404 | wz = 2.0f * bx * (q1q3 + q2q4) + 2.0f * bz * (0.5f - q2q2 - q3q3); |
icyzkungz | 6:5665d427bceb | 405 | |
icyzkungz | 6:5665d427bceb | 406 | // Error is cross product between estimated direction and measured direction of gravity |
icyzkungz | 6:5665d427bceb | 407 | ex = (ay * vz - az * vy) + (my * wz - mz * wy); |
icyzkungz | 6:5665d427bceb | 408 | ey = (az * vx - ax * vz) + (mz * wx - mx * wz); |
icyzkungz | 6:5665d427bceb | 409 | ez = (ax * vy - ay * vx) + (mx * wy - my * wx); |
icyzkungz | 6:5665d427bceb | 410 | if (Ki > 0.0f) { |
icyzkungz | 6:5665d427bceb | 411 | eInt[0] += ex; // accumulate integral error |
icyzkungz | 6:5665d427bceb | 412 | eInt[1] += ey; |
icyzkungz | 6:5665d427bceb | 413 | eInt[2] += ez; |
icyzkungz | 6:5665d427bceb | 414 | } else { |
icyzkungz | 6:5665d427bceb | 415 | eInt[0] = 0.0f; // prevent integral wind up |
icyzkungz | 6:5665d427bceb | 416 | eInt[1] = 0.0f; |
icyzkungz | 6:5665d427bceb | 417 | eInt[2] = 0.0f; |
icyzkungz | 6:5665d427bceb | 418 | } |
icyzkungz | 6:5665d427bceb | 419 | |
icyzkungz | 6:5665d427bceb | 420 | // Apply feedback terms |
icyzkungz | 6:5665d427bceb | 421 | gx = gx + Kp * ex + Ki * eInt[0]; |
icyzkungz | 6:5665d427bceb | 422 | gy = gy + Kp * ey + Ki * eInt[1]; |
icyzkungz | 6:5665d427bceb | 423 | gz = gz + Kp * ez + Ki * eInt[2]; |
icyzkungz | 6:5665d427bceb | 424 | |
icyzkungz | 6:5665d427bceb | 425 | // Integrate rate of change of quaternion |
icyzkungz | 6:5665d427bceb | 426 | pa = q2; |
icyzkungz | 6:5665d427bceb | 427 | pb = q3; |
icyzkungz | 6:5665d427bceb | 428 | pc = q4; |
icyzkungz | 6:5665d427bceb | 429 | q1 = q1 + (-q2 * gx - q3 * gy - q4 * gz) * (0.5f * deltat); |
icyzkungz | 6:5665d427bceb | 430 | q2 = pa + (q1 * gx + pb * gz - pc * gy) * (0.5f * deltat); |
icyzkungz | 6:5665d427bceb | 431 | q3 = pb + (q1 * gy - pa * gz + pc * gx) * (0.5f * deltat); |
icyzkungz | 6:5665d427bceb | 432 | q4 = pc + (q1 * gz + pa * gy - pb * gx) * (0.5f * deltat); |
icyzkungz | 6:5665d427bceb | 433 | |
icyzkungz | 6:5665d427bceb | 434 | // Normalise quaternion |
icyzkungz | 6:5665d427bceb | 435 | norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); |
icyzkungz | 6:5665d427bceb | 436 | norm = 1.0f / norm; |
icyzkungz | 6:5665d427bceb | 437 | q[0] = q1 * norm; |
icyzkungz | 6:5665d427bceb | 438 | q[1] = q2 * norm; |
icyzkungz | 6:5665d427bceb | 439 | q[2] = q3 * norm; |
icyzkungz | 6:5665d427bceb | 440 | q[3] = q4 * norm; |
icyzkungz | 6:5665d427bceb | 441 | |
icyzkungz | 6:5665d427bceb | 442 | yaw = atan2(2.0f * (q[1] * q[2] + q[0] * q[3]), q[0] * q[0] + q[1] * q[1] - q[2] * q[2] - q[3] * q[3]); |
icyzkungz | 6:5665d427bceb | 443 | pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2])); |
icyzkungz | 6:5665d427bceb | 444 | roll = atan2(2.0f * (q[0] * q[1] + q[2] * q[3]), q[0] * q[0] - q[1] * q[1] - q[2] * q[2] + q[3] * q[3]); |
icyzkungz | 6:5665d427bceb | 445 | |
icyzkungz | 6:5665d427bceb | 446 | Xh = mx*cos(pitch)+my*sin(roll)*sin(pitch)-mz*cos(roll)*sin(pitch); |
icyzkungz | 6:5665d427bceb | 447 | Yh = my*cos(roll)+mz*sin(roll); |
icyzkungz | 6:5665d427bceb | 448 | |
icyzkungz | 6:5665d427bceb | 449 | yawmag = atan2(Yh,Xh)+PI; |
icyzkungz | 6:5665d427bceb | 450 | ////////////test.printf("Xh= %f Yh= %f ",Xh,Yh); |
icyzkungz | 6:5665d427bceb | 451 | //////test.printf("Yaw[mag]= %f\n\r",yawmag*180.0f/PI); |
icyzkungz | 6:5665d427bceb | 452 | //test.printf(",%f",yawmag*180.0f/PI); |
icyzkungz | 6:5665d427bceb | 453 | |
icyzkungz | 6:5665d427bceb | 454 | |
icyzkungz | 6:5665d427bceb | 455 | |
icyzkungz | 6:5665d427bceb | 456 | pitch *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 457 | yaw *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 458 | yaw += 180.0f; // Declination at Danville, California is 13 degrees 48 minutes and 47 seconds on 2014-04-04 |
icyzkungz | 6:5665d427bceb | 459 | roll *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 460 | } |
icyzkungz | 6:5665d427bceb | 461 | |
icyzkungz | 6:5665d427bceb | 462 | void AHRS::TimeStart() |
icyzkungz | 6:5665d427bceb | 463 | { |
icyzkungz | 6:5665d427bceb | 464 | t.start(); |
icyzkungz | 6:5665d427bceb | 465 | } |
icyzkungz | 6:5665d427bceb | 466 | |
icyzkungz | 6:5665d427bceb | 467 | void AHRS::TimeCal() |
icyzkungz | 6:5665d427bceb | 468 | { |
icyzkungz | 6:5665d427bceb | 469 | Now = t.read_us(); |
icyzkungz | 6:5665d427bceb | 470 | deltat = (float)((Now - lastUpdate)/1000000.0f) ; // set integration time by time elapsed since last filter update |
icyzkungz | 6:5665d427bceb | 471 | lastUpdate = Now; |
icyzkungz | 6:5665d427bceb | 472 | |
icyzkungz | 6:5665d427bceb | 473 | sum += deltat; |
icyzkungz | 6:5665d427bceb | 474 | sumCount++; |
icyzkungz | 6:5665d427bceb | 475 | } |
icyzkungz | 6:5665d427bceb | 476 | |
icyzkungz | 6:5665d427bceb | 477 | void AHRS::Run() |
icyzkungz | 6:5665d427bceb | 478 | { |
icyzkungz | 6:5665d427bceb | 479 | ReadRawAccGyroMag(); |
icyzkungz | 6:5665d427bceb | 480 | TimeCal(); |
icyzkungz | 6:5665d427bceb | 481 | MadgwickQuaternionUpdate(); |
icyzkungz | 6:5665d427bceb | 482 | |
icyzkungz | 6:5665d427bceb | 483 | delt_t = t.read_ms() - count; |
icyzkungz | 6:5665d427bceb | 484 | if (delt_t > 500) { // update LCD once per half-second independent of read rate |
icyzkungz | 6:5665d427bceb | 485 | |
icyzkungz | 6:5665d427bceb | 486 | /*pc.printf("ax = %f", 1000*ax); |
icyzkungz | 6:5665d427bceb | 487 | pc.printf(" ay = %f", 1000*ay); |
icyzkungz | 6:5665d427bceb | 488 | pc.printf(" az = %f mg\n\r", 1000*az); |
icyzkungz | 6:5665d427bceb | 489 | |
icyzkungz | 6:5665d427bceb | 490 | pc.printf("gx = %f", gx); |
icyzkungz | 6:5665d427bceb | 491 | pc.printf(" gy = %f", gy); |
icyzkungz | 6:5665d427bceb | 492 | pc.printf(" gz = %f deg/s\n\r", gz); |
icyzkungz | 6:5665d427bceb | 493 | |
icyzkungz | 6:5665d427bceb | 494 | pc.printf("mx = %f", mx); |
icyzkungz | 6:5665d427bceb | 495 | pc.printf(" my = %f", my); |
icyzkungz | 6:5665d427bceb | 496 | pc.printf(" mz = %f mG\n\r", mz);*/ |
icyzkungz | 6:5665d427bceb | 497 | |
icyzkungz | 6:5665d427bceb | 498 | |
icyzkungz | 6:5665d427bceb | 499 | //pc.printf("%f,%f,%f",mx,my,mz); |
icyzkungz | 6:5665d427bceb | 500 | |
icyzkungz | 6:5665d427bceb | 501 | whoami = readByte(AK8963_ADDRESS, AK8963_ST2); // Read WHO_AM_I register for MPU-9250 |
icyzkungz | 6:5665d427bceb | 502 | // pc.printf("I AM 0x%x\n\r", whoami); pc.printf("I SHOULD BE 0x10\n\r"); |
icyzkungz | 6:5665d427bceb | 503 | if(whoami == 0x14) { |
icyzkungz | 6:5665d427bceb | 504 | printf("I AM 0x%x\n\r", whoami); |
icyzkungz | 6:5665d427bceb | 505 | while(1); |
icyzkungz | 6:5665d427bceb | 506 | } |
icyzkungz | 6:5665d427bceb | 507 | |
icyzkungz | 6:5665d427bceb | 508 | |
icyzkungz | 6:5665d427bceb | 509 | readTempData(); |
icyzkungz | 6:5665d427bceb | 510 | temperature = ((float) temperature) / 333.87f + 21.0f; // Temperature in degrees Centigrade |
icyzkungz | 6:5665d427bceb | 511 | //pc.printf(" temperature = %f C\n\r", temperature); |
icyzkungz | 6:5665d427bceb | 512 | |
icyzkungz | 6:5665d427bceb | 513 | // pc.printf("q0 = %f\n\r", q[0]); |
icyzkungz | 6:5665d427bceb | 514 | // pc.printf("q1 = %f\n\r", q[1]); |
icyzkungz | 6:5665d427bceb | 515 | // pc.printf("q2 = %f\n\r", q[2]); |
icyzkungz | 6:5665d427bceb | 516 | // pc.printf("q3 = %f\n\r", q[3]); |
icyzkungz | 6:5665d427bceb | 517 | |
icyzkungz | 6:5665d427bceb | 518 | // Define output variables from updated quaternion---these are Tait-Bryan angles, commonly used in aircraft orientation. |
icyzkungz | 6:5665d427bceb | 519 | // In this coordinate system, the positive z-axis is down toward Earth. |
icyzkungz | 6:5665d427bceb | 520 | // Yaw is the angle between Sensor x-axis and Earth magnetic North (or true North if corrected for local declination, looking down on the sensor positive yaw is counterclockwise. |
icyzkungz | 6:5665d427bceb | 521 | // Pitch is angle between sensor x-axis and Earth ground plane, toward the Earth is positive, up toward the sky is negative. |
icyzkungz | 6:5665d427bceb | 522 | // Roll is angle between sensor y-axis and Earth ground plane, y-axis up is positive roll. |
icyzkungz | 6:5665d427bceb | 523 | // These arise from the definition of the homogeneous rotation matrix constructed from quaternions. |
icyzkungz | 6:5665d427bceb | 524 | // Tait-Bryan angles as well as Euler angles are non-commutative; that is, the get the correct orientation the rotations must be |
icyzkungz | 6:5665d427bceb | 525 | // applied in the correct order which for this configuration is yaw, pitch, and then roll. |
icyzkungz | 6:5665d427bceb | 526 | // For more see http://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles which has additional links. |
icyzkungz | 6:5665d427bceb | 527 | yaw = atan2(2.0f * (q[1] * q[2] + q[0] * q[3]), q[0] * q[0] + q[1] * q[1] - q[2] * q[2] - q[3] * q[3]); |
icyzkungz | 6:5665d427bceb | 528 | pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2])); |
icyzkungz | 6:5665d427bceb | 529 | roll = atan2(2.0f * (q[0] * q[1] + q[2] * q[3]), q[0] * q[0] - q[1] * q[1] - q[2] * q[2] + q[3] * q[3]); |
icyzkungz | 6:5665d427bceb | 530 | |
icyzkungz | 6:5665d427bceb | 531 | Xh = mx*cos(pitch)+my*sin(roll)*sin(pitch)-mz*cos(roll)*sin(pitch); |
icyzkungz | 6:5665d427bceb | 532 | Yh = my*cos(roll)+mz*sin(roll); |
icyzkungz | 6:5665d427bceb | 533 | |
icyzkungz | 6:5665d427bceb | 534 | yawmag = atan2(Yh,Xh)+PI; |
icyzkungz | 6:5665d427bceb | 535 | //pc.printf("Xh= %f Yh= %f ",Xh,Yh); |
icyzkungz | 6:5665d427bceb | 536 | printf("Yaw[mag]= %f\n\r",yawmag*180.0f/PI); |
icyzkungz | 6:5665d427bceb | 537 | printf(",%f",yawmag*180.0f/PI); |
icyzkungz | 6:5665d427bceb | 538 | |
icyzkungz | 6:5665d427bceb | 539 | |
icyzkungz | 6:5665d427bceb | 540 | |
icyzkungz | 6:5665d427bceb | 541 | pitch *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 542 | yaw *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 543 | yaw += 180.0f; // Declination at Danville, California is 13 degrees 48 minutes and 47 seconds on 2014-04-04 |
icyzkungz | 6:5665d427bceb | 544 | roll *= 180.0f / PI; |
icyzkungz | 6:5665d427bceb | 545 | |
icyzkungz | 6:5665d427bceb | 546 | //pc.printf(",%f,%f,%f\n",roll,pitch,yaw); |
icyzkungz | 6:5665d427bceb | 547 | printf("Yaw, Pitch, Roll: %f %f %f\n\r", yaw, pitch, roll); |
icyzkungz | 6:5665d427bceb | 548 | //pc.printf("average rate = %f\n\r", (float) sumCount/sum); |
icyzkungz | 6:5665d427bceb | 549 | // sprintf(buffer, "YPR: %f %f %f", yaw, pitch, roll); |
icyzkungz | 6:5665d427bceb | 550 | // lcd.printString(buffer, 0, 4); |
icyzkungz | 6:5665d427bceb | 551 | // sprintf(buffer, "rate = %f", (float) sumCount/sum); |
icyzkungz | 6:5665d427bceb | 552 | // lcd.printString(buffer, 0, 5); |
icyzkungz | 6:5665d427bceb | 553 | |
icyzkungz | 6:5665d427bceb | 554 | |
icyzkungz | 6:5665d427bceb | 555 | |
icyzkungz | 6:5665d427bceb | 556 | |
icyzkungz | 6:5665d427bceb | 557 | myled= !myled; |
icyzkungz | 6:5665d427bceb | 558 | count = t.read_ms(); |
icyzkungz | 6:5665d427bceb | 559 | |
icyzkungz | 6:5665d427bceb | 560 | if(count > 1<<21) { |
icyzkungz | 6:5665d427bceb | 561 | t.start(); // start the timer over again if ~30 minutes has passed |
icyzkungz | 6:5665d427bceb | 562 | count = 0; |
icyzkungz | 6:5665d427bceb | 563 | deltat= 0; |
icyzkungz | 6:5665d427bceb | 564 | lastUpdate = t.read_us(); |
icyzkungz | 6:5665d427bceb | 565 | } |
icyzkungz | 6:5665d427bceb | 566 | sum = 0; |
icyzkungz | 6:5665d427bceb | 567 | sumCount = 0; |
icyzkungz | 6:5665d427bceb | 568 | } |
icyzkungz | 6:5665d427bceb | 569 | } |
icyzkungz | 6:5665d427bceb | 570 | |
icyzkungz | 6:5665d427bceb | 571 | void AHRS::printRollPitchYaw() |
icyzkungz | 6:5665d427bceb | 572 | { |
icyzkungz | 6:5665d427bceb | 573 | //test.printf("roll : %f, pitch : %f, yaw : %f\n",roll,pitch,yaw); |
icyzkungz | 6:5665d427bceb | 574 | } |