Diff: main.cpp

Revision:

0:e647f6de3d26

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Fri Mar 06 15:03:57 2020 +0000
@@ -0,0 +1,505 @@
+//==================================================
+//Auto pilot(prototype2)
+//
+//MPU board: mbed LPC1768
+//Multiplexer TC74HC157AP
+//Accelerometer +Gyro sensor : GY-521
+//2019/11/17 A.Toda
+//==================================================
+#include "mbed.h"
+#include "MPU6050.h"
+#include "SDFileSystem.h"
+
+#include "Vector.h"
+#include "Matrix.h"
+#include "Vector_Matrix_operator.h"
+
+#include "math.h"
+
+//==================================================
+#define RAD_TO_DEG          57.2957795f             // 180 / π
+#define MAX_MEAN_COUNTER 500
+
+#define ACC_X -1.205178682//offset of x-axi accelerometer
+#define ACC_Y -0.141728488//offset of y-axi accelerometer
+#define ACC_Z -0.339272785//offset of z-axi accelerometer
+
+#define ACC_GAIN_X 1.0
+#define ACC_GAIN_Y 0.995906146
+#define ACC_GAIN_Z 1.017766039
+
+#define THRESHOLD_PWM 0.0015
+#define M_A_PWM 0.0017
+#define SERVO_PERIOD  0.020
+
+#define PITCH_TARGET 0.0
+
+/*
+8/2/2020でのゲイン
+#define P_P_GAIN 3.0
+#define P_I_GAIN 0.5
+#define P_D_GAIN 1.0
+*/
+
+#define OFFSET_PWM_ELE 0.0015
+#define MAX_PWM_ELE 0.00175
+#define MIN_PWM_ELE 0.00125
+
+#define LPF_ELE_K 0.110//この値が小さいとローパスフィルタが強くなる 0.050は小さすぎる
+                        //0.200は動きが機敏過ぎる。
+//==================================================
+
+//Port Setting
+SDFileSystem sd(p5, p6, p7, p8, "sd");//pins for sd slot 
+MPU6050 mpu(p9, p10);  //Accelerometer + Gyro
+                        //(SDA,SCLK)
+DigitalIn logging_terminater(p16);
+InterruptIn reading_port(p18); 
+DigitalOut mux_switch(p19);
+PwmOut ELE(p21);
+
+Serial pc(USBTX, USBRX);    //UART
+
+//Pointer of sd card
+FILE *fp;
+
+//==================================================
+//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;
+
+double dev  =0.0;
+double i_dev=0.0;
+double d_dev=0.0;
+
+double old_i_dev=0.0;
+//==================================================
+//Atitude data
+//==================================================
+double roll_and_pitch_acc[2];//atitude from acceleromter
+double roll_and_pitch[2];//atitude from gyro and acceleromter
+
+/*--------------------------行列、ベクトル-----------------------------*/
+Matrix rate_angle_matrix(4,4);//角速度行列 クォータニオンの更新に使う
+Vector quaternion(4),pre_quaternion(4),dump_1(4);;//クォータニオン
+/*-------------------------------------------------------------------*/
+
+//==================================================
+//Timer valiables
+//==================================================
+Timer ch_time;//timer for calculate pulse width
+Timer passed_time;//timer for calculate atitude
+
+double measured_pre_pulse=0.0;
+double measured_pulse=0.0;
+
+double time_new;
+double time_old;
+
+double pulse_width_ele,deflection_ele,old_deflection_ele;
+
+//=================================================
+//PID Gain
+//==================================================
+float P_P_GAIN,P_I_GAIN,P_D_GAIN;
+int P_GAIN,I_GAIN,D_GAIN;
+
+//=================================================
+//エレベータの舵角
+//=================================================
+double pitch_command;
+
+//=================================================
+//手動か自動かのインジケータ0なら手動、1なら自動
+//=================================================
+int m_a_indicater;
+//=================================================
+//Functions for rising and falind edge interrution
+//=================================================
+//rise edge
+void rising_edge(){
+    ch_time.reset();//reset timer counter
+    measured_pre_pulse=ch_time.read();
+    
+}
+
+//falling edge
+void falling_edge(){
+    
+    measured_pre_pulse=(ch_time.read()-measured_pre_pulse);
+    //pc.printf("The pulse width=%f\r\n",measured_pre_pulse);
+    if(measured_pre_pulse>M_A_PWM){
+        mux_switch=1;
+        m_a_indicater=1;//set indicater as auto
+        }else{
+            mux_switch=0;
+            m_a_indicater=0;//set indicater as manual
+            }
+}
+
+//terminate logging
+void end_of_log(){
+     //flipper.detach();
+     fclose(fp);//close "Atitude_angles.csv"
+     pc.printf("Logging was terminated.");
+     
+    }
+//==================================================
+//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[2]*=(-1.0);
+    
+    ac[0]=(ac[0]-ACC_X)/ACC_GAIN_X;
+    ac[1]=(ac[1]-ACC_Y)/ACC_GAIN_Y;
+    ac[2]=(ac[2]-ACC_Z)/ACC_GAIN_Z;
+            
+    //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] = 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
+    
+    return;
+}
+
+//quaternion to euler
+void quaternion_to_euler(Vector& qua,double *roll_and_pitch ){
+    
+    double q0=double (qua.GetComp(1));
+    double q1=double (qua.GetComp(2));
+    double q2=double (qua.GetComp(3));
+    double q3=double (qua.GetComp(4));
+    
+    roll_and_pitch[0]=atan((q2*q3+q0*q1)/(q0*q0-q1*q1-q2*q2+q3*q3)) ;//roll
+    roll_and_pitch[1]=-asin(2*(q1*q3-q0*q2));
+    
+    return;
+    }
+
+//quaternion to euler
+void euler_to_quaternion(Vector& qua,double *roll_and_pitch ){
+    
+    double roll_rad_2=(roll_and_pitch[0]/57.3)/2.0;
+    double pitch_rad_2=(roll_and_pitch[1]/57.3)/2.0;
+    double yaw_rad_2=0.0;
+    
+    float q0= cos(roll_rad_2)*cos(pitch_rad_2)*cos(yaw_rad_2)
+                +sin(roll_rad_2)*sin(pitch_rad_2)*sin(yaw_rad_2);
+                
+    float q1= sin(roll_rad_2)*cos(pitch_rad_2)*cos(yaw_rad_2)
+                -cos(roll_rad_2)*sin(pitch_rad_2)*sin(yaw_rad_2);
+                
+    float q2= cos(roll_rad_2)*sin(pitch_rad_2)*cos(yaw_rad_2)
+                +sin(roll_rad_2)*cos(pitch_rad_2)*sin(yaw_rad_2);
+
+    float q3= cos(roll_rad_2)*cos(pitch_rad_2)*sin(yaw_rad_2)
+                -sin(roll_rad_2)*sin(pitch_rad_2)*cos(yaw_rad_2);
+
+    //クォータニオン行列の作成（クォータニオンの演算に用いる）
+    float quaternion_elements[4]={q0,q1,q2,q3}; 
+    qua.SetComps(quaternion_elements);
+    
+    
+    return;
+    }
+
+//atitude calculation
+void atitude_update(){
+    
+    //慣性センサの計測
+    aquisition_sensor_values(acc,gyro);
+    //角速度行列の作成（クォータニオンの演算に用いる）
+    float rate_angles[16]={0.0,-float(gyro[0]),-float(gyro[1]),-float(gyro[2])
+                          ,float(gyro[0]),0.0,float(gyro[2]),-float(gyro[1])
+                          ,float(gyro[1]),-float(gyro[2]),0.0,float(gyro[0])
+                          ,float(gyro[0]),float(gyro[1]),-float(gyro[2]),0.0}; 
+                          
+    rate_angle_matrix.SetComps(rate_angles);
+    //クォータニオンの演算
+    //pc.printf("クォータニオンの演算\r\n");
+    float coefficents=0.5*(time_new-time_old);
+    float coefficents_elements[16]={coefficents,0.0,0.0,0.0
+                                      ,0.0,coefficents,0.0,0.0
+                                      ,0.0,0.0,coefficents,0.0
+                                      ,0.0,0.0,0.0,coefficents};
+    Vector coefficents_vector(4);
+    coefficents_vector.SetComps(coefficents_elements);
+    
+    dump_1=rate_angle_matrix*coefficents_vector;
+    quaternion=dump_1+pre_quaternion;
+    
+    //正規化
+    //pc.printf("正規化\r\n");
+    quaternion=quaternion.Normalize();
+    //クォータニオンからオイラー角への変換
+    quaternion_to_euler(quaternion,roll_and_pitch_acc );
+    
+    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];
+        
+        }else{}
+    //補正したオイラー角をクォータニオンへ変換
+    euler_to_quaternion(pre_quaternion,roll_and_pitch_acc );
+    
+    //microSDに記録する
+    //経過時間,ロール角,ピッチ角,操縦方式,慣性センサの値
+    fprintf(fp, "%f,%f,%f,%d,%f,%f,%f,%f,%f,%f\r\n"
+        ,time_new,roll_and_pitch[0],roll_and_pitch[1],m_a_indicater,gyro[0],gyro[1],acc[0],acc[1],acc[2],pitch_command);
+    
+    return;
+
+}
+
+//elevation commnad to PWM
+double elevation_to_PWM(double elevation_command){
+    
+    /*
+    PWM信号0.25msが舵角の16.45度に相当する.
+    */
+    
+    double PWM_pitch = (elevation_command*1.519)/100000+ OFFSET_PWM_ELE;
+    //double PWM_pitch = ( ((elevation_command)*6.0/1000.0)/1000.0  )+ OFFSET_PWM_ELE;
+    
+    /*PWMコマンドの上限と下限の設定*/
+    if(PWM_pitch>MAX_PWM_ELE){
+        PWM_pitch=MAX_PWM_ELE;
+        
+        }else if(PWM_pitch<MIN_PWM_ELE){
+            PWM_pitch=MIN_PWM_ELE;
+            }
+    
+    return PWM_pitch;
+    
+    }
+
+double deflection_of_ele(double pitch){
+    
+    double add_deflection=((pitch-PITCH_TARGET)*6.0/1000.0)/1000.0;
+    
+    return add_deflection;
+    }
+
+//PID controller
+double pitch_PID_controller(double pitch,double target,double gyro_pitch){
+    
+    dev=target-pitch;
+    
+    //アンチワインドアップ
+    i_dev=old_i_dev+dev*(time_new-time_old);
+    if(i_dev>=25.0){
+        i_dev=25.0;
+    }else if(i_dev<=-25.0){
+        i_dev=-25.0;
+    }
+    //アンチワインドアップ終わり
+            
+    old_i_dev=i_dev;
+    
+    d_dev=-gyro_pitch;
+    
+    pitch_command = double(P_P_GAIN*dev+P_I_GAIN*i_dev+P_D_GAIN*d_dev);
+    
+    double pwm_command = elevation_to_PWM(pitch_command);//pwm信号に変換
+    
+    return pwm_command;
+
+    }
+
+//LPF
+
+double LPF_pitch(double c_com,double old_com){
+    
+    double lpf_output=(1-LPF_ELE_K)*old_com+LPF_ELE_K*c_com;
+    
+    return lpf_output;
+    }
+
+//==================================================
+//Main
+//==================================================
+int main() {
+
+    wait(5.0);
+    
+    //UART initialization
+    pc.baud(115200);
+    
+    //define servo period
+    ELE.period(SERVO_PERIOD);  // servo requires a 20ms period
+    pulse_width_ele=0.0015;
+    
+    //timer starts
+    ch_time.start();
+    passed_time.start();
+    
+    time_old=0.0;
+    
+    //declare interrupitons
+    reading_port.rise(rising_edge);
+    reading_port.fall(falling_edge);
+    
+    /*
+    mux_switch=0;//set circit as manual mode
+    m_a_indicater=0;//set indicater as manual
+    */
+    
+    //gyro and accelerometer initialization
+    offset_calculation_for_gyro();
+    
+    //determine initilal atitude
+    aquisition_sensor_values(acc,gyro);
+    atitude_estimation_from_accelerometer(acc,roll_and_pitch);
+    euler_to_quaternion(pre_quaternion,roll_and_pitch);
+    
+    threshold_acc_ini=sqrt(acc[0]*acc[0]+acc[1]*acc[1]+acc[2]*acc[2]);
+    
+    /*
+    PIDゲインをsdカードのテキストファイルから読み取る
+    int型しか読みとれないので、希望する値の10倍をテキストファイルに書き込んでいる。
+    Pゲインを3.0,Iゲインを0.5,Dゲインを1.0とする場合
+    
+    30,5,10
+    
+    のようにテキストデータをsdカードに用意する。  
+    */
+    //open PID gain file in sd card 
+    FILE*ga = fopen("/sd/Gain_data.txt", "r");
+    if(ga == NULL) {
+        error("Could not open file for write\n");
+    }
+    
+    while (!feof(ga)) {
+        int n = fscanf(ga, "%d,%d,%d",&P_GAIN, &I_GAIN, &D_GAIN);
+        
+        if(n!= 3){
+            error("Could not read 3 elements");
+            }
+    }
+    
+    P_P_GAIN=P_GAIN/10.0;
+    P_I_GAIN=I_GAIN/10.0;
+    P_D_GAIN=D_GAIN/10.0;
+    
+    fclose(ga);
+    
+    //create folder(sd) in sd card
+    mkdir("/sd", 0777);
+    //create "Atitude_angles.csv" in folder(sd)
+    fp = fopen("/sd/Atitude_angles.csv", "a");//ファイルがある場合は追加で書き込み
+        
+    if(fp == NULL) {
+        error("Could not open file for write\n");
+    }
+    
+    //Logging starts
+    pc.printf("Logging starts.");
+    
+    //write PID gain on sd card 
+    fprintf(fp,"%f,%f,%f\r\n",P_P_GAIN,P_I_GAIN,P_D_GAIN);
+    
+    //while
+    while(1){
+         
+         if(logging_terminater==1){
+             end_of_log();
+             }else{}
+         
+         time_new=passed_time.read();
+         
+         atitude_update();
+        
+         time_old=time_new;
+         
+         /*
+         ここから先でサーボの操舵角を姿勢角に応じて変化させる。関数pitch_PID_controller
+         はpitch角とpitch角速度に応じてサーボのパルス幅を返す関数である。
+         */
+         
+         deflection_ele = pitch_PID_controller(roll_and_pitch[1],PITCH_TARGET,gyro[1]);
+         
+         //LPF
+         deflection_ele = LPF_pitch(deflection_ele,old_deflection_ele);
+         old_deflection_ele = deflection_ele;
+         
+         //servo output
+         ELE.pulsewidth(deflection_ele);
+         
+         //PCにつないでデバッグを行う際に表示する
+         pc.printf("%f,%f,%f,%f,%d\r\n",time_new,deflection_ele,roll_and_pitch[0],roll_and_pitch[1],m_a_indicater);
+         
+         wait(0.002);
+        
+    }//while ends
+    
+}//main ends
\ No newline at end of file