ドローン用計測制御基板の作り方 vol.1 ハードウェア編 p.16掲載 相補フィルタによる姿勢角推定
Dependencies: mbed MPU6050_alter
main.cpp
- Committer:
- Joeatsumi
- Date:
- 2019-12-30
- Revision:
- 0:06770dc62477
File content as of revision 0:06770dc62477:
//================================================== //Atitude estimation (compensated filter) //MPU board: mbed LPC1768 //Accelerometer +Gyro sensor : GY-521 //2019/10/11 A.Toda //================================================== #include "mbed.h" #include "MPU6050.h" //================================================== #define RAD_TO_DEG 57.2957795f // 180 / π #define MAX_MEAN_COUNTER 100 #define ACC_X 1.3//offset of x-axi accelerometer //================================================== //Timer interrupt Ticker flipper; //Port Setting MPU6050 mpu(p9, p10); //Accelerometer + Gyro //(SDA,SCLK) Serial pc(USBTX, USBRX); //UART //================================================== //Accelerometer and gyro data //================================================== double acc[3]; //variables for accelerometer double gyro[3]; //variables for gyro double offset_gyro_x=0.0; double offset_gyro_y=0.0; double sum_gyro_x=0.0; double sum_gyro_y=0.0; double threshold_acc,threshold_acc_ini; //================================================== //Atitude data //================================================== double roll_and_pitch_acc[2];//atitude from acceleromter double roll_and_pitch[2];//atitude from gyro and acceleromter //================================================== //Gyro and accelerometer functions //================================================== //get data void aquisition_sensor_values(double *a,double *g){ float ac[3],gy[3]; mpu.getAccelero(ac);//get acceleration (Accelerometer) //x_axis acc[0] //y_axis acc[1] //z_axis acc[2] mpu.getGyro(gy); //get rate of angle(Gyro) //x_axis gyro[0] //y_axis gyro[1] //z_axis gyro[2] //Invertion for direction of Accelerometer axis ac[0]*=(-1.0); ac[0]+=ACC_X; ac[2]*=(-1.0); //Unit convertion of rate of angle(radian to degree) gy[0]*=RAD_TO_DEG; gy[0]*=(-1.0); gy[1]*=RAD_TO_DEG; gy[2]*=RAD_TO_DEG; gy[2]*=(-1.0); for(int i=0;i<3;i++){ a[i]=double(ac[i]); g[i]=double(gy[i]); } g[0]-=offset_gyro_x;//offset rejection g[1]-=offset_gyro_y;//offset rejection return; } //calculate offset of gyro void offset_calculation_for_gyro(){ //Accelerometer and gyro setting mpu.setAcceleroRange(0);//acceleration range is +-2G mpu.setGyroRange(1);//gyro rate is +-500degree per second(dps) //calculate offset of gyro for(int mean_counter=0; mean_counter<MAX_MEAN_COUNTER ;mean_counter++){ aquisition_sensor_values(acc,gyro); sum_gyro_x+=gyro[0]; sum_gyro_y+=gyro[1]; wait(0.01); } offset_gyro_x=sum_gyro_x/MAX_MEAN_COUNTER; offset_gyro_y=sum_gyro_y/MAX_MEAN_COUNTER; return; } //atitude calculation from acceleromter void atitude_estimation_from_accelerometer(double *a,double *roll_and_pitch){ //roll_and_pitch[0] = atan2(a[1], a[2])*RAD_TO_DEG;//roll roll_and_pitch[0] = atan(a[1]/a[2])*RAD_TO_DEG;//roll //roll_and_pitch[1] = atan(a[0]/sqrt( a[1]*a[1]+a[2]*a[2] ) )*RAD_TO_DEG;//pitch roll_and_pitch[1] = atan2(a[0],sqrt( a[1]*a[1]+a[2]*a[2] ) )*RAD_TO_DEG;//pitch return; } //atitude calculation void atitude_update(){ aquisition_sensor_values(acc,gyro); roll_and_pitch[0]+=gyro[0]*0.01; roll_and_pitch[1]+=gyro[1]*0.01; threshold_acc=sqrt(acc[0]*acc[0]+acc[1]*acc[1]+acc[2]*acc[2]); if((threshold_acc>=0.9*threshold_acc_ini) &&(threshold_acc<=1.1*threshold_acc_ini)){ atitude_estimation_from_accelerometer(acc,roll_and_pitch_acc); roll_and_pitch[0] = 0.98*roll_and_pitch[0] + 0.02*roll_and_pitch_acc[0]; //roll_and_pitch[1] = 0.98*roll_and_pitch[1] + 0.02*roll_and_pitch_acc[1]; roll_and_pitch[1] = roll_and_pitch_acc[1]; }else{} pc.printf("roll=%f pitch=%f\r\n",roll_and_pitch[0],roll_and_pitch[1]); return; } //================================================== //Main //================================================== int main() { //UART initialization pc.baud(115200); //gyro and accelerometer initialization offset_calculation_for_gyro(); //identify initilal atitude aquisition_sensor_values(acc,gyro); atitude_estimation_from_accelerometer(acc,roll_and_pitch); threshold_acc_ini=sqrt(acc[0]*acc[0]+acc[1]*acc[1]+acc[2]*acc[2]); //Ticker flipper.attach(&atitude_update, 0.01); //while while(1) { wait(0.01); } }