TrekkingPhoenix / Mbed 2 deprecated TrekkingControllerV1-4_WinterChallenge20

Ironcup Mar 2020

Dependencies:   mbed mbed-rtos MotionSensor EthernetInterface

main.cpp@0:88faaa1afb83, 2016-04-11 (annotated)

Committer:
drelliak
Date:
Mon Apr 11 05:20:40 2016 +0000
Revision:
0:88faaa1afb83
Child:
1:3f923c2862c9
Trekking Controller

Who changed what in which revision?

UserRevisionLine numberNew contents of line
drelliak 0:88faaa1afb83 1 #include "FXAS21002.h"
drelliak 0:88faaa1afb83 2 #include "FXOS8700Q.h"
drelliak 0:88faaa1afb83 3 #include "mbed.h"
drelliak 0:88faaa1afb83 4 #include "CarPWM.h"
drelliak 0:88faaa1afb83 5 #include "receiver.h"
drelliak 0:88faaa1afb83 6
drelliak 0:88faaa1afb83 7
drelliak 0:88faaa1afb83 8 #define PI 3.141592653589793238462
drelliak 0:88faaa1afb83 9 #define Ts 0.02 // Seconds
drelliak 0:88faaa1afb83 10 #define INITIAL_P 0.452531214933414
drelliak 0:88faaa1afb83 11 #define INITIAL_I 5.45748932024049
drelliak 0:88faaa1afb83 12 #define INITIAL_D 0.000233453623255507
drelliak 0:88faaa1afb83 13 #define INITIAL_N 51.0605584484153
drelliak 0:88faaa1afb83 14 #define GYRO_OFFSET 0.0152
drelliak 0:88faaa1afb83 15 #define END_THRESH 4
drelliak 0:88faaa1afb83 16 #define START_THRESH 10
drelliak 0:88faaa1afb83 17 #define MINIMUM_VELOCITY 15
drelliak 0:88faaa1afb83 18 Serial ser(USBTX, USBRX); // Initialize Serial port
drelliak 0:88faaa1afb83 19 PwmOut motor(PTD1); // Motor connected to pin PTD1
drelliak 0:88faaa1afb83 20 PwmOut servo(PTD3); // Servo connected to pin PTD3
drelliak 0:88faaa1afb83 21
drelliak 0:88faaa1afb83 22 FXOS8700Q_mag mag(PTE25,PTE24,FXOS8700CQ_SLAVE_ADDR1);
drelliak 0:88faaa1afb83 23 FXAS21002 gyro(PTE25,PTE24);
drelliak 0:88faaa1afb83 24
drelliak 0:88faaa1afb83 25
drelliak 0:88faaa1afb83 26
drelliak 0:88faaa1afb83 27 // PID controller parameters and functions
drelliak 0:88faaa1afb83 28 float e[2], u, up[1],ui[2], ud[2]; // The vector coeficient means a time delay, for exemple e[a] = e(k-a) -> z^(-a)e(k)
drelliak 0:88faaa1afb83 29 float P, I, D, N, reference = 0;
drelliak 0:88faaa1afb83 30 void controlAnglePID(float P, float I, float D, float N);
drelliak 0:88faaa1afb83 31 void initializeController();
drelliak 0:88faaa1afb83 32
drelliak 0:88faaa1afb83 33 // Gyroscope variables and functions
drelliak 0:88faaa1afb83 34 float gyro_data[3], gyro_angle;
drelliak 0:88faaa1afb83 35 Timer t;
drelliak 0:88faaa1afb83 36 void processGyroAngle();
drelliak 0:88faaa1afb83 37 void startGyro();
drelliak 0:88faaa1afb83 38 void stopGyro();
drelliak 0:88faaa1afb83 39
drelliak 0:88faaa1afb83 40 // Magnetometer variables and functions
drelliak 0:88faaa1afb83 41 float max_x, max_y, min_x, min_y,x,y;
drelliak 0:88faaa1afb83 42 MotionSensorDataUnits mag_data;
drelliak 0:88faaa1afb83 43 float processMagAngle();
drelliak 0:88faaa1afb83 44 void magCal();
drelliak 0:88faaa1afb83 45
drelliak 0:88faaa1afb83 46 // State variables
drelliak 0:88faaa1afb83 47 float sensor, velocity;
drelliak 0:88faaa1afb83 48 void readProtocol();
drelliak 0:88faaa1afb83 49 void brakeMotor();
drelliak 0:88faaa1afb83 50 // Test functions
drelliak 0:88faaa1afb83 51 void debug();
drelliak 0:88faaa1afb83 52
drelliak 0:88faaa1afb83 53 int main(){
drelliak 0:88faaa1afb83 54 // Initializing serial communication
drelliak 0:88faaa1afb83 55 ser.baud(9600);
drelliak 0:88faaa1afb83 56 ser.format(8, SerialBase::None, 1);
drelliak 0:88faaa1afb83 57 // Initializing controller
drelliak 0:88faaa1afb83 58 printf("Initializing controller....\r\n\r\n");
drelliak 0:88faaa1afb83 59 initializeController();
drelliak 0:88faaa1afb83 60 printf("Controller Initialized. \r\n");
drelliak 0:88faaa1afb83 61 // Calibrating magnetometer and setting the initial position
drelliak 0:88faaa1afb83 62 magCal();
drelliak 0:88faaa1afb83 63 gyro_angle = processMagAngle();
drelliak 0:88faaa1afb83 64 // Start moving the robot and integrating the gyroscope
drelliak 0:88faaa1afb83 65 velocity = MINIMUM_VELOCITY;
drelliak 0:88faaa1afb83 66 setMotorPWM(velocity,motor);
drelliak 0:88faaa1afb83 67 startGyro();
drelliak 0:88faaa1afb83 68 // main loop
drelliak 0:88faaa1afb83 69 while (true){
drelliak 0:88faaa1afb83 70 processGyroAngle();
drelliak 0:88faaa1afb83 71 controlAnglePID(P,I,D,N);
drelliak 0:88faaa1afb83 72 //debug();
drelliak 0:88faaa1afb83 73 if(t.read_us() < Ts*1000000)
drelliak 0:88faaa1afb83 74 wait_us(Ts*1000000 - t.read_us());
drelliak 0:88faaa1afb83 75 if(ser.readable())
drelliak 0:88faaa1afb83 76 readProtocol();
drelliak 0:88faaa1afb83 77 }
drelliak 0:88faaa1afb83 78 }
drelliak 0:88faaa1afb83 79
drelliak 0:88faaa1afb83 80 void readProtocol(){
drelliak 0:88faaa1afb83 81 char msg = ser.getc();
drelliak 0:88faaa1afb83 82 switch(msg)
drelliak 0:88faaa1afb83 83 {
drelliak 0:88faaa1afb83 84 case NONE:
drelliak 0:88faaa1afb83 85 //ser.printf("sending red signal to led\r\n");
drelliak 0:88faaa1afb83 86 return;
drelliak 0:88faaa1afb83 87 break;
drelliak 0:88faaa1afb83 88 case BRAKE:
drelliak 0:88faaa1afb83 89 //ser.printf("sending green signal to led\r\n");
drelliak 0:88faaa1afb83 90 brakeMotor();
drelliak 0:88faaa1afb83 91 break;
drelliak 0:88faaa1afb83 92 case ANG_RST:
drelliak 0:88faaa1afb83 93 //ser.printf("sending blue signal to led\r\n");
drelliak 0:88faaa1afb83 94 stopGyro();
drelliak 0:88faaa1afb83 95 gyro_angle = 0;
drelliak 0:88faaa1afb83 96 startGyro();
drelliak 0:88faaa1afb83 97 return;
drelliak 0:88faaa1afb83 98 break;
drelliak 0:88faaa1afb83 99 case ANG_REF:
drelliak 0:88faaa1afb83 100 reference = get_ang_ref(ser);
drelliak 0:88faaa1afb83 101 break;
drelliak 0:88faaa1afb83 102 case GND_SPEED:
drelliak 0:88faaa1afb83 103 velocity = get_gnd_speed(ser);
drelliak 0:88faaa1afb83 104 setMotorPWM(velocity,motor);
drelliak 0:88faaa1afb83 105 break;
drelliak 0:88faaa1afb83 106 case PID_PARAMS:
drelliak 0:88faaa1afb83 107 ser.putc('p');
drelliak 0:88faaa1afb83 108 get_pid_params(ser, &P, &I, &D, &N);
drelliak 0:88faaa1afb83 109 break;
drelliak 0:88faaa1afb83 110 default:
drelliak 0:88faaa1afb83 111 // ser.flush();
drelliak 0:88faaa1afb83 112
drelliak 0:88faaa1afb83 113 }
drelliak 0:88faaa1afb83 114 }
drelliak 0:88faaa1afb83 115 /* Initialize the controller parameter P, I, D and N with the initial values and set the error and input to 0. */
drelliak 0:88faaa1afb83 116 void initializeController(){
drelliak 0:88faaa1afb83 117 for(int i =0; i<2; i++){
drelliak 0:88faaa1afb83 118 e[i] = 0;
drelliak 0:88faaa1afb83 119 ui[i] = 0;
drelliak 0:88faaa1afb83 120 ud[i] = 0;
drelliak 0:88faaa1afb83 121 }
drelliak 0:88faaa1afb83 122 P= INITIAL_P;
drelliak 0:88faaa1afb83 123 I= INITIAL_I;
drelliak 0:88faaa1afb83 124 D= INITIAL_D;
drelliak 0:88faaa1afb83 125 N= INITIAL_N;
drelliak 0:88faaa1afb83 126 }
drelliak 0:88faaa1afb83 127
drelliak 0:88faaa1afb83 128 /* Start the Gyroscope timer and set the initial configuration */
drelliak 0:88faaa1afb83 129 void startGyro(){
drelliak 0:88faaa1afb83 130 gyro.gyro_config();
drelliak 0:88faaa1afb83 131 t.start();
drelliak 0:88faaa1afb83 132 }
drelliak 0:88faaa1afb83 133
drelliak 0:88faaa1afb83 134 /* Stop and reset the Gyroscope */
drelliak 0:88faaa1afb83 135 void stopGyro(){
drelliak 0:88faaa1afb83 136 t.stop();
drelliak 0:88faaa1afb83 137 t.reset();
drelliak 0:88faaa1afb83 138 gyro_angle = 0;
drelliak 0:88faaa1afb83 139 }
drelliak 0:88faaa1afb83 140
drelliak 0:88faaa1afb83 141 /* Integrate the Gyroscope to get the angular position (Deegre/seconds) */
drelliak 0:88faaa1afb83 142 void processGyroAngle(){
drelliak 0:88faaa1afb83 143 gyro.acquire_gyro_data_dps(gyro_data);
drelliak 0:88faaa1afb83 144 t.stop();
drelliak 0:88faaa1afb83 145 gyro_angle = gyro_angle + (gyro_data[2] + GYRO_OFFSET)*(double)(t.read_us())/1000000;
drelliak 0:88faaa1afb83 146 t.reset();
drelliak 0:88faaa1afb83 147 t.start();
drelliak 0:88faaa1afb83 148 sensor = gyro_angle;
drelliak 0:88faaa1afb83 149 if(sensor > 180)
drelliak 0:88faaa1afb83 150 sensor = sensor - 360;
drelliak 0:88faaa1afb83 151 if(sensor < -180)
drelliak 0:88faaa1afb83 152 sensor = sensor + 360;
drelliak 0:88faaa1afb83 153 }
drelliak 0:88faaa1afb83 154
drelliak 0:88faaa1afb83 155 /* PID controller for angular position */
drelliak 0:88faaa1afb83 156 void controlAnglePID(float P, float I, float D, float N){
drelliak 0:88faaa1afb83 157 /* Getting error */
drelliak 0:88faaa1afb83 158 e[1] = e[0];
drelliak 0:88faaa1afb83 159 e[0] = reference - (sensor*PI/180);
drelliak 0:88faaa1afb83 160 if(e[0] > PI)
drelliak 0:88faaa1afb83 161 e[0]= e[0] - 2*PI;
drelliak 0:88faaa1afb83 162 if(e[0] < -PI)
drelliak 0:88faaa1afb83 163 e[0] = e[0] + 2*PI;
drelliak 0:88faaa1afb83 164 /* Proportinal Part */
drelliak 0:88faaa1afb83 165 up[0] = e[0]*P;
drelliak 0:88faaa1afb83 166 /* Integral Part */
drelliak 0:88faaa1afb83 167 ui[1] = ui[0];
drelliak 0:88faaa1afb83 168 if(abs(u) < PI/8){
drelliak 0:88faaa1afb83 169 ui[0] = (P*I*Ts)*e[1] + ui[1];
drelliak 0:88faaa1afb83 170 }
drelliak 0:88faaa1afb83 171 else if(u > 0)
drelliak 0:88faaa1afb83 172 ui[0] = PI/8 - up[0];
drelliak 0:88faaa1afb83 173 else if(u < 0)
drelliak 0:88faaa1afb83 174 ui[0] = -PI/8 - up[0];
drelliak 0:88faaa1afb83 175 /* Derivative Part */
drelliak 0:88faaa1afb83 176 ud[1] = ud[0];
drelliak 0:88faaa1afb83 177 ud[0] = P*D*N*(e[0] - e[1]) - ud[1]*(N*Ts -1);
drelliak 0:88faaa1afb83 178 /** Controller **/
drelliak 0:88faaa1afb83 179 u = up[0] + ud[0] + ui[0];
drelliak 0:88faaa1afb83 180 setServoPWM(u*100/(PI/8), servo);
drelliak 0:88faaa1afb83 181 }
drelliak 0:88faaa1afb83 182 /* Brake function, braking while the gyroscope is still integrating will cause considerably error in the measurement. */
drelliak 0:88faaa1afb83 183 void brakeMotor(){
drelliak 0:88faaa1afb83 184 if(velocity > 0)
drelliak 0:88faaa1afb83 185 setMotorPWM(-30, motor);
drelliak 0:88faaa1afb83 186 else if(velocity < 0)
drelliak 0:88faaa1afb83 187 setMotorPWM(30, motor);
drelliak 0:88faaa1afb83 188 wait(0.5);
drelliak 0:88faaa1afb83 189 setMotorPWM(0,motor);
drelliak 0:88faaa1afb83 190 }
drelliak 0:88faaa1afb83 191 /* Debug functions that prints the sensor and control inputs values. Since it's time consuming it should not be used */
drelliak 0:88faaa1afb83 192 /* in the main loop or the controller performance may be affected. */
drelliak 0:88faaa1afb83 193 void debug(){
drelliak 0:88faaa1afb83 194 //printf("ERROR: %f Up: %f Ui: %f Ud: %f U: %f \r\n", e[0]*180/3.1415, up[0]*100/(3.1415/8), ui[0]*100/(3.1415/8), ud[0]*100/(3.1415/8),u*100/(3.1415/8));
drelliak 0:88faaa1afb83 195 //printf("Erro: %f Sensor: %f Magnetometer: %f \r\n",e[0]*180/PI,sensor,processMagAngle(0)*180/PI);
drelliak 0:88faaa1afb83 196 printf(" %f \r\n",sensor);
drelliak 0:88faaa1afb83 197 }
drelliak 0:88faaa1afb83 198
drelliak 0:88faaa1afb83 199 /* Function to normalize the magnetometer reading */
drelliak 0:88faaa1afb83 200 void magCal(){
drelliak 0:88faaa1afb83 201 printf("Starting Calibration");
drelliak 0:88faaa1afb83 202 mag.enable();
drelliak 0:88faaa1afb83 203 wait(0.01);
drelliak 0:88faaa1afb83 204 mag.getAxis(mag_data);
drelliak 0:88faaa1afb83 205 float x0 = max_x = min_y = mag_data.x;
drelliak 0:88faaa1afb83 206 float y0 = max_y = min_y = mag_data.y;
drelliak 0:88faaa1afb83 207 bool began = false;
drelliak 0:88faaa1afb83 208 while(!(began && abs(mag_data.x - x0) < END_THRESH && abs(mag_data.y - y0) < END_THRESH)){
drelliak 0:88faaa1afb83 209 mag.getAxis(mag_data);
drelliak 0:88faaa1afb83 210 if(mag_data.x > max_x)
drelliak 0:88faaa1afb83 211 max_x = mag_data.x;
drelliak 0:88faaa1afb83 212 if(mag_data.y > max_y)
drelliak 0:88faaa1afb83 213 max_y = mag_data.y;
drelliak 0:88faaa1afb83 214 if(mag_data.y < min_y)
drelliak 0:88faaa1afb83 215 min_y = mag_data.y;
drelliak 0:88faaa1afb83 216 if(mag_data.x < min_x)
drelliak 0:88faaa1afb83 217 min_x = mag_data.x;
drelliak 0:88faaa1afb83 218 if(abs(mag_data.x-x0)>START_THRESH && abs(mag_data.y-y0) > START_THRESH)
drelliak 0:88faaa1afb83 219 began = true;
drelliak 0:88faaa1afb83 220 printf("began: %d X-X0: %f , Y-Y0: %f \n\r", began, abs(mag_data.x-x0),abs(mag_data.y-y0));
drelliak 0:88faaa1afb83 221 }
drelliak 0:88faaa1afb83 222 printf("Calibration Completed: X_MAX = %f , Y_MAX = %f , X_MIN = %f and Y_MIN = %f \n\r",max_x,max_y,min_x,min_y);
drelliak 0:88faaa1afb83 223 }
drelliak 0:88faaa1afb83 224
drelliak 0:88faaa1afb83 225 /* Function to transform the magnetometer reading in angle(rad/s).*/
drelliak 0:88faaa1afb83 226 float processMagAngle(){
drelliak 0:88faaa1afb83 227 mag.getAxis(mag_data);
drelliak 0:88faaa1afb83 228 x = 2*(mag_data.x-min_x)/float(max_x-min_x) - 1;
drelliak 0:88faaa1afb83 229 y = 2*(mag_data.y-min_y)/float(max_y-min_y) - 1;
drelliak 0:88faaa1afb83 230 return atan2(y,x);
drelliak 0:88faaa1afb83 231 }