hige dura
/
IMU
main.cpp
- Committer:
- higedura
- Date:
- 2012-02-15
- Revision:
- 2:78c3d0598819
- Parent:
- 1:aca0c191fb1c
- Child:
- 3:9f3e1a43f68f
File content as of revision 2:78c3d0598819:
// IMU for Sparkfun 9DOF Sensor Stick #include "ADXL345_I2C.h" #include "ITG3200.h" #include "HMC5883L.h" DigitalOut led1(LED1); DigitalOut led2(LED2); DigitalOut led3(LED3); DigitalOut led4(LED4); ADXL345_I2C accelerometer(p9, p10); ITG3200 gyro(p9, p10); HMC5883L compass(p9, p10); Serial pc(USBTX, USBRX); #define pi 3.14159265 #define N 3 #define N_LWMA 10 double* RK4( double, double[N], double[N] ); double* func( double[N], double[N] ); double* LWMA( double[N] ); double* EKF_predict( double[N], double[N] ); double* EKF_correct( double[N], double[N], double[N] ); // 0 1 2 // [ accXn-1 accXn-2 ... ] 0 // zBuf = [ accYn-1 accYn-2 ... ] 1 // [ accZn-1 accZn-2 ... ] 2 double z_buf[N][N_LWMA] = {0}; // For LWMA double P[N][N] = {{1,0,0},{0,1,0},{0,0,1}}; // For EKF int main(){ pc.baud(921600); // loop int correct_loop = 0; int calib_loop = 1000; double dt = 0.01; double t = 0; int bit_acc[N] = {0}; // Buffer of the accelerometer int get_mag[N] = {0}; // Buffer of the compass // For calibration routine double calib_acc[N] = {0}; double calib_gyro_buf[N] = {0}; double calib_gyro[N] = {0}; double compass_basis_buf[N] = {0}; double compass_basis_rad = 0; // For getting data double acc[N] = {0}; double gyro_deg[N] = {0}; double gyro_rad[N] = {0}; int mag[N] = {0}; // For measurement algorithm double ang_acc[2] = {0}; double ang_deg[N] = {0}; double ang_rad[N] = {0}; double zLWMA[N] = {0}; double compass_rad = 0; double compass_deg = 0; for( int i=0;i<N_LWMA;i++ ){ z_buf[2][i] = 1; } double* p_ang_RK4; double* p_ang_EKF; double* p_zLWMA_buf; // *** Setting up accelerometer *** // These are here to test whether any of the initialization fails. It will print the failure. if(accelerometer.setPowerControl(0x00)){ pc.printf("didn't intitialize power control\n\r"); return 0; } // Full resolution, +/-16g, 4mg/LSB. wait(.001); if(accelerometer.setDataFormatControl(0x0B)){ pc.printf("didn't set data format\n\r"); return 0; } wait(.001); // 3.2kHz data rate. if(accelerometer.setDataRate(ADXL345_3200HZ)){ pc.printf("didn't set data rate\n\r"); return 0; } wait(.001); if(accelerometer.setPowerControl(MeasurementMode)) { pc.printf("didn't set the power control to measurement\n\r"); return 0; } // *** Setting up accelerometer *** // *** Setting up gyro *** gyro.setLpBandwidth(LPFBW_42HZ); // *** Setting up compass *** compass.setDefault(); // Wait some time for all sensors (Need at least 5ms) wait(0.1); // *** Calibration routine *** pc.printf("\n\rDont touch!! Calibrating now ...\n\r"); led1 = 1; for( int i=0;i<calib_loop;i++ ){ accelerometer.getOutput(bit_acc); compass.readData(get_mag); calib_gyro_buf[0] = gyro.getGyroX(); calib_gyro_buf[1] = gyro.getGyroY(); calib_gyro_buf[2] = gyro.getGyroZ(); for( int j=0;j<N;j++ ){ calib_acc[j] += (int16_t)bit_acc[j]; calib_gyro[j] += calib_gyro_buf[j]; compass_basis_buf[j] += (int16_t)get_mag[j]; } if( i>calib_loop*3/4 ){ led4 = 1; }else if( i>calib_loop/2 ){ led3 = 1; }else if( i>calib_loop/4 ){ led2 = 1; } } for( int i=0;i<N;i++ ){ calib_acc[i] = calib_acc[i]/calib_loop; calib_gyro[i] = calib_gyro[i]/calib_loop; compass_basis_buf[i] = compass_basis_buf[i]/calib_loop; } compass_basis_rad = compass_basis_buf[1]/compass_basis_buf[0]; compass_basis_rad = atan(compass_basis_rad); led1 = 0; led2 = 0; led3 = 0; led4 = 0; pc.printf("accX accY accZ gyroX gyroY gyroZ yaw_basis\n\r"); pc.printf("%f, %f, %f, %f, %f, %f, %f\n\r",calib_acc[0],calib_acc[1],calib_acc[2],calib_gyro[0],calib_gyro[1],calib_gyro[2],compass_basis_rad*180/pi); for( int i=0;i<3;i++ ){ wait(0.5); led1 = 1; led2 = 1; led3 = 1; led4 = 1; wait(0.5); led1 = 0; led2 = 0; led3 = 0; led4 = 0; } // *** Calibration routine *** pc.printf("Starting IMU unit \n\r"); pc.printf(" Time AccX AccY AccZ GyroX GyroY GyroZ MagX MagY MagZ\n\r"); while(1){ // Updating accelerometer and compass accelerometer.getOutput(bit_acc); compass.readData(get_mag); // Transfering units (Acc[g], Gyro[deg/s], Compass[Ga]) acc[0] = ((int16_t)bit_acc[0]-calib_acc[0])*0.004; acc[1] = ((int16_t)bit_acc[1]-calib_acc[1])*0.004; acc[2] = ((int16_t)bit_acc[2]-calib_acc[2])*0.004+1; for( int i=0;i<N;i++ ){ gyro_deg[i] = (gyro.getGyroX()-calib_gyro[i])/14.375; } for( int i=0;i<N;i++ ){ mag[0] = (int16_t)get_mag[0]; } // Low pass filter for acc //for( int i=0;i<N;i++ ){ if( -0.05<acc[i] && acc[i]<0.05 ){ acc[i] = 0; } } for( int i=0;i<N;i++ ){ if( acc[i]<-2 ){ acc[i] = -2; } } for( int i=0;i<N;i++ ){ if( acc[i]>2 ){ acc[i] = 2; } } // Low pass filter for gyro for( int i=0;i<N;i++ ){ if( -0.5<gyro_deg[i] && gyro_deg[i]<0.5 ){ gyro_deg[i] = 0; } } for( int i=0;i<N;i++ ){ gyro_rad[i] = gyro_deg[i]*pi/180; } // Compass yaw compass_rad = (double)mag[1]/mag[0]; compass_rad = atan(compass_rad); //compass_rad = compass_rad-compass_basis_rad; compass_deg = compass_rad*180/pi; // LWMA (Observation) p_zLWMA_buf = LWMA(acc); for( int i=0;i<N;i++ ){ zLWMA[i] = *p_zLWMA_buf; p_zLWMA_buf = p_zLWMA_buf+1; } // LWMA angle if( zLWMA[2]>0.98 ){ for( int i=0;i<2;i++ ){ ang_acc[i] = 0; } }else{ ang_acc[0] = asin(-zLWMA[1])*180/pi; ang_acc[1] = asin(zLWMA[0])*180/pi; } // RK4 (Prediction) p_ang_RK4 = RK4(dt,ang_rad,gyro_rad); for( int i=0;i<N;i++ ){ ang_rad[i] = *p_ang_RK4; p_ang_RK4 = p_ang_RK4+1; } // EKF (Correction) EKF_predict(ang_rad,gyro_rad); correct_loop++; if (correct_loop>=3){ p_ang_EKF = EKF_correct(ang_rad,gyro_rad,zLWMA); for ( int i=0;i<N;i++ ){ ang_deg[i] = *p_ang_EKF; p_ang_EKF = p_ang_EKF+1; } correct_loop = 0; } for( int i=0;i<N;i++ ){ ang_deg[i] = ang_rad[i]*180/pi; } //pc.printf("%7.2f, %7.3f, %7.3f, %7.3f, %7.1f, %7.1f, %7.1f, %5d, %5d, %5d\n\r", t, acc[0], acc[1], acc[2], gyro_deg[0], gyro_deg[1], gyro_deg[2], mag[0], mag[1], mag[2]); //pc.printf("%7.2f, %7.3f, %7.3f, %7.3f, %7.1f, %7.1f, %7.1f\n\r", t, acc[0], acc[1], acc[2], gyro_deg[0], gyro_deg[1], gyro_deg[2]); //pc.printf("%7.2f, %7.1f, %7.1f, %7.1f, %7.1f, %7.1f, %7.1f\n\r", t, gyro_deg[0], gyro_deg[1], gyro_deg[2], ang_deg[0], ang_deg[1], ang_deg[2]); //pc.printf("%7.2f, %7.3f, %7.3f, %7.3f, %7.3f, %7.3f, %7.3f\n\r", t, acc[0], acc[1], acc[2], zLWMA[0], zLWMA[1], zLWMA[2]); //pc.printf("%7.2f, %7.3f, %7.3f, %7.3f, %7.3f, %7.3f\n\r", t, zLWMA[0], zLWMA[1], zLWMA[2], ang_acc[0], ang_acc[1]); //pc.printf("%d, %d, %f\n\r",mag[0], mag[1], compass_deg); pc.printf("%7.2f, %7.3f, %7.3f, %7.1f, %7.1f, %7.1f\n\r", t, ang_acc[0], ang_acc[1], ang_deg[0], ang_deg[1], ang_deg[2]); wait(dt); t += dt; } } double* EKF_predict( double y[N], double x[N] ){ // x = F * x; // P = F * P * F' + G * Q * G'; double Q[N][N] = { {0.1, 0, 0}, {0, 0.1, 0}, {0, 0, 0.1} }; double Fjac[N][N] = {{x[1]*cos(y[0])*tan(y[1])-x[2]*sin(y[0])*tan(y[1]), x[1]*sin(y[0])/(cos(y[1])*cos(y[1]))+x[2]*cos(y[0])/(cos(y[1])*cos(y[1])), 0}, {-x[1]*sin(y[0])-x[2]*cos(y[0]), 0, 0}, {x[1]*cos(y[0])/cos(y[1])-x[2]*sin(y[0])/cos(y[1]), x[1]*sin(y[0])*sin(y[1])/(cos(y[1])*cos(y[1]))+x[2]*cos(y[0])*sin(y[1])/(cos(y[1])*cos(y[1])), 0}}; double Fjac_t[N][N] = {{x[1]*cos(y[0])*tan(y[1])-x[2]*sin(y[0])*tan(y[1]), -x[1]*sin(y[0])-x[2]*cos(y[0]), x[1]*cos(y[0])/cos(y[1])-x[2]*sin(y[0])/cos(y[1])}, {x[1]*sin(y[0])/(cos(y[1])*cos(y[1]))+x[2]*cos(y[0])/(cos(y[1])*cos(y[1])), 0, x[1]*sin(y[0])*sin(y[1])/(cos(y[1])*cos(y[1]))+x[2]*cos(y[0])*sin(y[1])/(cos(y[1])*cos(y[1]))}, {0, 0, 0}}; double Gjac[N][N] = {{1, sin(y[0])*tan(y[1]), cos(y[0])*tan(y[1])}, {0, cos(y[0]), -sin(y[0])}, {0, sin(y[0])/cos(y[1]), cos(y[0])/cos(y[1])}}; double Gjac_t[N][N] = {{1, 0, 0}, {sin(y[0])*tan(y[1]), cos(y[0]), sin(y[0])/cos(y[1])}, {cos(y[0])*tan(y[1]), -sin(y[0]), cos(y[0])/cos(y[1])}}; double FPF[N][N] = {0}; double GQG[N][N] = {0}; double FP[N][N] = {0}; double GQ[N][N] = {0}; for( int i=0;i<N;i++ ){ for( int j=0;j<N;j++ ){ for( int k=0;k<N;k++ ){ FP[i][j] += Fjac[i][k]*P[k][j]; GQ[i][j] += Gjac[i][k]*Q[k][j]; } } } for( int i=0;i<N;i++ ){ for( int j=0;j<N;j++ ){ for( int k=0;k<N;k++ ){ FPF[i][j] += FP[i][k]*Fjac_t[k][j]; GQG[i][j] += GQ[i][k]*Gjac_t[k][j]; } } } for( int i=0;i<N;i++ ){ for( int j=0;j<N;j++ ){ P[i][j] = FPF[i][j]+GQG[i][j]; } } return 0; } double* EKF_correct( double y[N], double x[N], double z[N] ){ // K = P * H' / ( H * P * H' + R ) // x = x + K * ( yobs(t) - H * x ) // P = P - K * H * P double R[N][N] = { {0.15, 0, 0}, {0, 0.15, 0}, {0, 0, 0.15} }; double Hjac[N][N] = {{0, cos(y[1]), 0}, {cos(y[0]), 0, 0}, {-sin(y[0])*cos(y[1]), -cos(y[0])*sin(y[1]), 0}}; double Hjac_t[N][N] = {{0, cos(y[0]), -sin(y[0])*cos(y[1])}, {cos(y[1]), 0, -cos(y[0])*sin(y[1])}, {0, 0, 0}}; double K[N][N] = {0}; // Kalman gain double K_deno[N][N] = {0}; // Denominator of the kalman gain double det_K_deno_inv = 0; double K_deno_inv[N][N] = {0}; double HPH[N][N] = {0}; double HP[N][N] = {0}; double PH[N][N] = {0}; double KHP[N][N] = {0}; double Hx[N] = {0}; double z_Hx[N] = {0}; double Kz_Hx[N] = {0}; double* py = y; // Kalman gain for( int i=0;i<N;i++ ){ for( int j=0;j<N;j++ ){ for( int k=0;k<N;k++ ){ HP[i][j] += Hjac[i][k]*P[k][j]; PH[i][j] += P[i][k]*Hjac_t[k][j]; } } } for( int i=0;i<N;i++ ){ for( int j=0;j<N;j++ ){ for( int k=0;k<N;k++ ){ HPH[i][j] += HP[i][k]*Hjac_t[k][j]; } } } for( int i=0;i<N;i++ ){ for( int j=0;j<N;j++ ){ K_deno[i][j] = HPH[i][j]+R[i][j]; } } // Inverce det_K_deno_inv = K_deno[0][0]*K_deno[1][1]*K_deno[2][2]+K_deno[1][0]*K_deno[2][1]*K_deno[0][2]+K_deno[2][0]*K_deno[0][1]*K_deno[1][2]-K_deno[0][0]*K_deno[2][1]*K_deno[1][2]-K_deno[2][0]*K_deno[1][1]*K_deno[0][2]-K_deno[1][0]*K_deno[0][1]*K_deno[2][2]; K_deno_inv[0][0] = (K_deno[1][1]*K_deno[2][2]-K_deno[1][2]*K_deno[2][1])/det_K_deno_inv; K_deno_inv[0][1] = (K_deno[0][2]*K_deno[2][1]-K_deno[0][1]*K_deno[2][2])/det_K_deno_inv; K_deno_inv[0][2] = (K_deno[0][1]*K_deno[1][2]-K_deno[0][2]*K_deno[1][1])/det_K_deno_inv; K_deno_inv[1][0] = (K_deno[1][2]*K_deno[2][0]-K_deno[1][0]*K_deno[2][2])/det_K_deno_inv; K_deno_inv[1][1] = (K_deno[0][0]*K_deno[2][2]-K_deno[0][2]*K_deno[2][0])/det_K_deno_inv; K_deno_inv[1][2] = (K_deno[0][2]*K_deno[1][0]-K_deno[0][0]*K_deno[1][2])/det_K_deno_inv; K_deno_inv[2][0] = (K_deno[1][0]*K_deno[2][1]-K_deno[1][1]*K_deno[2][0])/det_K_deno_inv; K_deno_inv[2][1] = (K_deno[0][1]*K_deno[2][0]-K_deno[0][0]*K_deno[2][1])/det_K_deno_inv; K_deno_inv[2][2] = (K_deno[0][0]*K_deno[1][1]-K_deno[0][1]*K_deno[1][0])/det_K_deno_inv; for( int i=0;i<N;i++ ){ for( int j=0;j<N;j++ ){ for( int k=0;k<N;k++ ){ K[i][j] += PH[i][k]*K_deno_inv[k][j]; } } } // Filtering for( int i=0;i<N;i++ ){ for( int j=0;j<N;j++ ){ Hx[i] += Hjac[i][j]*y[j]; } } for( int i=0;i<N;i++ ){ z_Hx[i] = z[i]-Hx[i]; } for( int i=0;i<N;i++ ){ for( int j=0;j<N;j++ ){ Kz_Hx[i] += K[i][j]*z_Hx[j]; } } for( int i=0;i<N;i++ ){ y[i] = y[i]+Kz_Hx[i]; } // Covarience for( int i=0;i<N;i++ ){ for( int j=0;j<N;j++ ){ for( int k=0;k<N;k++ ){ KHP[i][j] += K[i][k]*HP[k][j]; } } } for( int i=0;i<N;i++ ){ for( int j=0;j<N;j++ ){ P[i][j] = P[i][j]-KHP[i][j]; } } return py; } double* LWMA( double z[N] ){ double zLWMA[N] = {0}; double zLWMA_num[N] = {0}; double zLWMA_den = 0; double* pzLWMA = zLWMA; // �n�� for( int i=1;i<N_LWMA;i++ ){ for( int j=0;j<N;j++ ){ z_buf[j][N_LWMA-i] = z_buf[j][N_LWMA-i-1]; } } for( int i=0;i<N;i++ ){ z_buf[i][0] = z[i]; } // �v�Z���[�v for( int i=0;i<N_LWMA;i++ ){ for( int j=0;j<N;j++ ){ zLWMA_num[j] += (N_LWMA-i)*z_buf[j][i]; } zLWMA_den += N_LWMA-i; } for( int i=0;i<N;i++ ){ zLWMA[i] = zLWMA_num[i]/zLWMA_den; } return pzLWMA; } double* RK4( double dt, double y[N], double x[N] ){ double yBuf[N] = {0}; double k[N][4] = {0}; double* p_y = y; double* pk1; double* pk2; double* pk3; double* pk4; for( int i=0;i<N;i++){ yBuf[i] = y[i]; } pk1 = func (yBuf,x); for( int i=0;i<N;i++ ){ k[i][0] = *pk1; pk1 = pk1+1; } for( int i=0;i<N;i++){ yBuf[i] = y[i]+0.5*dt*k[i][1]; } pk2 = func (yBuf,x); for( int i=0;i<N;i++ ){ k[i][1] = *pk2; pk2 = pk2+1; } for( int i=0;i<N;i++){ yBuf[i] = y[i]+0.5*dt*k[i][2]; } pk3 = func (yBuf,x); for( int i=0;i<N;i++ ){ k[i][2] = *pk3; pk3 = pk3+1; } for( int i=0;i<N;i++){ yBuf[i] = y[i]+dt*k[i][3]; } pk4 = func (yBuf,x); for( int i=0;i<N;i++ ){ k[i][3] = *pk4; pk4 = pk4+1; } for( int i=0;i<N;i++){ y[i] = y[i]+dt*(k[i][0]+2.0*k[i][1]+2.0*k[i][2]+k[i][3])/6.0; } return p_y; } double* func( double y[N], double x[N] ){ double f[N] = {0}; double* p_f = f; f[0] = x[0]+x[1]*sin(y[0])*tan(y[1])+x[2]*cos(y[0])*tan(y[1]); f[1] = x[1]*cos(y[0])-x[2]*sin(y[0]); f[2] = x[1]*sin(y[0])/cos(y[1])+x[2]*cos(y[0])/cos(y[1]); return p_f; }