PID Controller
Dependencies: HIDScope MODSERIAL PinDetect QEI biquadFilter
Diff: pidControl.cpp
- Revision:
- 2:53d2f9b8fed1
- Parent:
- 1:fe23126b0389
- Child:
- 4:a722452d8fd1
diff -r fe23126b0389 -r 53d2f9b8fed1 pidControl.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/pidControl.cpp Tue Oct 20 08:04:38 2015 +0000 @@ -0,0 +1,213 @@ +#include "mbed.h" +#include "QEI.h" +#include "HIDScope.h" +#include "MODSERIAL.h" +#include "PinDetect.h" +#include "pidControl.h" +#include "biquadFilter.h" + +Serial pc(USBTX, USBRX); + +PinDetect stop(SW2); +PinDetect start(SW3); +AnalogIn pot1(m1_pot); +AnalogIn pot2(m2_pot); + +// PWM Speed Control: +DigitalOut dir1(m1_dir); +PwmOut pwm1(m1_pwm); +DigitalOut dir2(m2_dir); +PwmOut pwm2(m2_pwm); + +QEI enc1(m1_enc_a, m1_enc_b, NC, 1); +QEI enc2(m2_enc_a, m2_enc_b, NC, 1); + +Ticker potTicker; +Ticker motorTicker; + +Ticker graphTicker; +//HIDScope grapher(4); + +float currentRotation1 = 0, currentRotation2 = 0; +float desiredRotation1 = 0, desiredRotation2 = 0; +double error1 = 0, error2 = 0; + +double m1_error_integral = 0, m2_error_integral = 0; +double m1_error_derivative = 0, m2_error_derivative = 0; +biquadFilter m1_filter(m1_f_a1, m1_f_a2, m1_f_b0, m1_f_b1, m1_f_b2); +biquadFilter m2_filter(m2_f_a1, m2_f_a2, m2_f_b0, m2_f_b1, m2_f_b2); + +bool shutup = true; +bool go_pot = false; +bool go_motor = false; +bool go_graph = false; + +float getPotRad(AnalogIn pot) +{ + return pot.read() * 4.0f - 2.0f; +} + +float toRadians(int pulses) +{ + int remaining = pulses;// % sigPerRev; + float percent = (float) remaining / (float) sigPerRev; + return percent * 2.0f; +} + +void readPot() +{ + go_pot = true; +} + +void getMotorRotation() +{ + go_motor = true; +} + +void stopMotors() +{ + shutup = true; +} + +void startMotors() +{ + shutup = false; +} + +void sendGraph() +{ + go_graph = true; +} + +double p_control(double error, double kp) +{ + return kp * error; +} + +double pi_control(double error, double kp, double ki, double ts, double &error_integral) +{ + error_integral = error_integral + ts * error; + double result = kp * error + ki * error_integral; + return result; +} + +double pid_control(double error, double kp, double ki, double ts, double &error_integral, + double kd, double previous_error, double &error_derivative, biquadFilter filter) +{ + error_integral = error_integral + ts * error; + error_derivative = (error - previous_error) / ts; + // error_derivative = filter.step(error_derivative); + + double result = kp * error + ki * error_integral + kd * error_derivative; + return result; +} + +int getPDirection(double control, int motor) +{ + if (control >= 0) + return (motor == 1)?1:0; + else + return (motor == 1)?0:1; +} + +void initialize() +{ + pc.printf("Initializing...\r\n"); + + // Set the shutup and start buttons + stop.mode(PullUp); + stop.attach_deasserted(&stopMotors); + stop.setSampleFrequency(); + start.mode(PullUp); + start.attach_deasserted(&startMotors); + start.setSampleFrequency(); + + pc.printf("Buttons done\r\n"); + + // Set proper baudrate + // pc.baud(115200); + + // Reset encoders + enc1.reset(); + enc2.reset(); + pc.printf("Encoders reset\r\n"); + + // Start tickers + potTicker.attach(&readPot, tickRate); + motorTicker.attach(&getMotorRotation, tickRate); + graphTicker.attach(&sendGraph, graphTickRate); + pc.printf("Tickers attached\r\n"); + + pc.printf("Initialized\r\n"); +} + +int main() +{ + pc.printf("Started\r\n"); + initialize(); + + while (true) { + if (shutup) { + pwm1 = 0; + pwm2 = 0; + } else { + if (go_pot) { + desiredRotation1 = getPotRad(pot1); + desiredRotation2 = getPotRad(pot2); + + go_pot = false; + } + + if (go_motor) { + currentRotation1 = toRadians(enc1.getPulses()); + currentRotation2 = toRadians(enc2.getPulses()); + + pc.printf("PULSE: %i | CUR ROT: %f | ERR: %f | DES ROT: %f\r\n",enc2.getPulses(),currentRotation2, error2,desiredRotation2); + + double previous_error1 = error1; + double previous_error2 = error2; + + error1 = desiredRotation1 - currentRotation1; + error2 = desiredRotation2 - currentRotation2; + // P control + // double control1 = p_control(error1, motor1_kp); + // double control2 = p_control(error2, motor2_kp); + + // PI control + //double control1 = pi_control(error1, motor1_kp, motor1_ki, tickRate, m1_error_integral); + // double control2 = pi_control(error2, motor2_kp, motor2_ki, tickRate, m2_error_integral); + + // PID control + double control1 = pid_control(error1, motor1_kp, motor1_ki, tickRate, m1_error_integral, motor1_kd, previous_error1, m1_error_derivative, m1_filter); + double control2 = pid_control(error2, motor2_kp, motor2_ki, tickRate, m2_error_integral, motor2_kd, previous_error2, m2_error_derivative, m2_filter); + + int d1 = getPDirection(control1,1); + int d2 = getPDirection(control2,2); + float speed1 = fabs(control1); + float speed2 = fabs(control2); + + if (speed1 < 0.1f) speed1 = 0.0f; + if (speed2 < 0.1f) speed2 = 0.0f; + dir1 = d1; + dir2 = d2; + pwm1 = speed1; + pwm2 = speed2; + pc.printf("SPEED: %f | DIR: %i\r\n",speed2,d2); + + go_motor = false; + } + + /*if (go_graph) { + pc.printf("Trying to send graph\r\n"); + pc.printf("Desired Rotation: %f %f\r\n", desiredRotation1, desiredRotation2); + pc.printf("Rotation: %f %f\r\n", currentRotation1, desiredRotation2); + grapher.set(0, desiredRotation1); + grapher.set(1, currentRotation1); + grapher.set(2, desiredRotation2); + grapher.set(3, currentRotation2); + grapher.send(); + go_graph = false; + }*/ + } + } +}