No.9 Robotics / Mbed 2 deprecated Robotics_Servo_control

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Dependencies:   mbed

Fork of Robotics_Lab_Servo by LDSC_Robotics

main.cpp@3:71a807b38a3e, 2016-03-10 (annotated)

Committer:
dg0704
Date:
Thu Mar 10 06:22:25 2016 +0000
Revision:
3:71a807b38a3e
Parent:
2:a3c64321e9c2
Child:
4:facfa2ac9a59
add Kp and Ki;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
YCTung 0:564d77fcaa70 1 /*LAB_SERVO*/
YCTung 0:564d77fcaa70 2 #include "mbed.h"
YCTung 0:564d77fcaa70 3
YCTung 0:564d77fcaa70 4 //The number will be compiled as type "double" in default
YCTung 0:564d77fcaa70 5 //Add a "f" after the number can make it compiled as type "float"
YCTung 1:3b6c9baa7d0c 6 #define Ts 0.01f //period of timer1 (s)
YCTung 2:a3c64321e9c2 7 #define Kp 0.053f
YCTung 2:a3c64321e9c2 8 #define Ki 0.013f
YCTung 0:564d77fcaa70 9
YCTung 0:564d77fcaa70 10 PwmOut servo(A0);
dg0704 3:71a807b38a3e 11 PwmOut pwm1(PA_8);
dg0704 3:71a807b38a3e 12 PwmOut pwm1n(PB_13);
YCTung 0:564d77fcaa70 13
YCTung 0:564d77fcaa70 14 AnalogIn adc(A2);//Temporary usage
YCTung 0:564d77fcaa70 15
YCTung 0:564d77fcaa70 16 //LED1 = D13 = PA_5 (LED on Nucleo board)
YCTung 0:564d77fcaa70 17 DigitalOut led1(LED1);
YCTung 0:564d77fcaa70 18 DigitalOut led2(D12);
YCTung 0:564d77fcaa70 19
YCTung 0:564d77fcaa70 20 Ticker timer1;
YCTung 1:3b6c9baa7d0c 21 void timer1_interrupt(void);
YCTung 0:564d77fcaa70 22
YCTung 1:3b6c9baa7d0c 23 void init_TIMER(void);
YCTung 0:564d77fcaa70 24 void init_IO(void);
YCTung 0:564d77fcaa70 25 void init_PWM(void);
YCTung 1:3b6c9baa7d0c 26 void flash(void);
YCTung 0:564d77fcaa70 27
YCTung 1:3b6c9baa7d0c 28 //Variable(s) for PI controller
YCTung 2:a3c64321e9c2 29 float angle_ref = 0.0; //unit in degree(s), range +-90 degrees
YCTung 2:a3c64321e9c2 30 float angle_read= 0.0;
YCTung 2:a3c64321e9c2 31 float angle_check;
YCTung 0:564d77fcaa70 32 float err = 0.0;
YCTung 0:564d77fcaa70 33 float ierr = 0.0;
YCTung 0:564d77fcaa70 34 float PI_out = 0.0;
YCTung 0:564d77fcaa70 35 float pwm1_duty = 0.5;
dg0704 3:71a807b38a3e 36 float kp = 0.025;
dg0704 3:71a807b38a3e 37 float ki = 0.025;
YCTung 0:564d77fcaa70 38
YCTung 1:3b6c9baa7d0c 39 int main (void)
YCTung 1:3b6c9baa7d0c 40 {
YCTung 1:3b6c9baa7d0c 41 init_IO();
YCTung 1:3b6c9baa7d0c 42 init_PWM();
YCTung 1:3b6c9baa7d0c 43 init_TIMER();
YCTung 1:3b6c9baa7d0c 44 while(1)
YCTung 1:3b6c9baa7d0c 45 {
YCTung 1:3b6c9baa7d0c 46 ;
YCTung 1:3b6c9baa7d0c 47 }
YCTung 1:3b6c9baa7d0c 48 }
YCTung 1:3b6c9baa7d0c 49
YCTung 0:564d77fcaa70 50 void timer1_interrupt(void)
YCTung 0:564d77fcaa70 51 {
YCTung 2:a3c64321e9c2 52 angle_read = (adc.read() - 0.45f) / 0.48f * 180.0f; //0.21 ~ 0.69 respect to -90 ~ +90 degree
YCTung 2:a3c64321e9c2 53 angle_check = angle_read;
YCTung 0:564d77fcaa70 54
YCTung 1:3b6c9baa7d0c 55 //////code for PI control//////
dg0704 3:71a807b38a3e 56 err = angle_ref - angle_read;
dg0704 3:71a807b38a3e 57 ierr = 0.01f/(err-1);
dg0704 3:71a807b38a3e 58 PI_out = kp*err+ki*ierr;
YCTung 2:a3c64321e9c2 59
YCTung 0:564d77fcaa70 60 ////////////
YCTung 0:564d77fcaa70 61 if(PI_out >= 0.5f)PI_out = 0.5;
YCTung 0:564d77fcaa70 62 else if(PI_out <= -0.5f)PI_out = -0.5;
YCTung 0:564d77fcaa70 63 pwm1_duty = PI_out + 0.5f;
YCTung 2:a3c64321e9c2 64 if(angle_check > 100.0f || angle_check < -100.0f)pwm1_duty = 0.5;
YCTung 0:564d77fcaa70 65 pwm1.write(pwm1_duty);
dg0704 3:71a807b38a3e 66 TIM1->CCER |= 0x4; //enable ch1 complementary output
dg0704 3:71a807b38a3e 67
YCTung 0:564d77fcaa70 68 }
YCTung 0:564d77fcaa70 69
YCTung 0:564d77fcaa70 70 void init_TIMER(void)
YCTung 0:564d77fcaa70 71 {
YCTung 0:564d77fcaa70 72 timer1.attach_us(&timer1_interrupt, 10000);//10ms interrupt period (100 Hz)
YCTung 0:564d77fcaa70 73 }
YCTung 0:564d77fcaa70 74
YCTung 0:564d77fcaa70 75 void init_IO(void)
YCTung 0:564d77fcaa70 76 {
YCTung 0:564d77fcaa70 77 led1 = 0;
YCTung 0:564d77fcaa70 78 led2 = 1;
YCTung 0:564d77fcaa70 79 }
YCTung 0:564d77fcaa70 80
YCTung 0:564d77fcaa70 81 void init_PWM(void)
YCTung 0:564d77fcaa70 82 {
YCTung 0:564d77fcaa70 83 pwm1.period_us(50);
YCTung 0:564d77fcaa70 84 pwm1.write(0.5);
YCTung 0:564d77fcaa70 85 TIM1->CCER |= 0x4;
YCTung 0:564d77fcaa70 86 }
YCTung 0:564d77fcaa70 87
YCTung 0:564d77fcaa70 88 void flash(void)
YCTung 0:564d77fcaa70 89 {
YCTung 0:564d77fcaa70 90 led1 = !led1;
YCTung 0:564d77fcaa70 91 }