
PID controller test code
Dependencies: mbed Encoder HIDScope
main.cpp@2:323606a75d64, 2015-10-13 (annotated)
- Committer:
- S1lverEagle
- Date:
- Tue Oct 13 13:42:53 2015 +0000
- Revision:
- 2:323606a75d64
- Parent:
- 1:64ec36ba6e76
- Child:
- 3:c4c2d42cedd4
Motor werkt, code niet
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
S1lverEagle | 1:64ec36ba6e76 | 1 | #include "mbed.h" |
S1lverEagle | 1:64ec36ba6e76 | 2 | #include "encoder.h" |
S1lverEagle | 0:88e83d97a0ee | 3 | |
S1lverEagle | 0:88e83d97a0ee | 4 | Ticker control_ticker; |
S1lverEagle | 2:323606a75d64 | 5 | PwmOut pwm_motor1(D5); //onderste motor |
S1lverEagle | 2:323606a75d64 | 6 | DigitalOut dir_motor1(D4); |
S1lverEagle | 0:88e83d97a0ee | 7 | AnalogIn potmeter1(A4); |
S1lverEagle | 1:64ec36ba6e76 | 8 | Encoder encoder1(D13,D12,true); |
S1lverEagle | 1:64ec36ba6e76 | 9 | double pos_1; |
S1lverEagle | 0:88e83d97a0ee | 10 | |
S1lverEagle | 0:88e83d97a0ee | 11 | // Sample time (motor1−timestep) |
S1lverEagle | 0:88e83d97a0ee | 12 | const double m1_Ts = 0.01; |
S1lverEagle | 0:88e83d97a0ee | 13 | // Controller gains (motor1−Kp,−Ki,...) |
S1lverEagle | 0:88e83d97a0ee | 14 | const double m1_Kp = 2.5, m1_Ki = 1.0, m1_Kd = 0.5; |
S1lverEagle | 0:88e83d97a0ee | 15 | double m1_err_int = 0, m1_prev_err = 0; |
S1lverEagle | 0:88e83d97a0ee | 16 | // Derivative filter coeicients (motor1−filter−b0,−b1,...) |
S1lverEagle | 0:88e83d97a0ee | 17 | const double m1_f_a1 = 1.0, m1_f_a2 = 2.0, m1_f_b0 = 1.0, m1_f_b1 = 3.0, m1_f_b2 = 4.0; |
S1lverEagle | 0:88e83d97a0ee | 18 | // Filter variables (motor1−filter−v1,−v2) |
S1lverEagle | 0:88e83d97a0ee | 19 | double m1_f_v1 = 0, m1_f_v2 = 0; |
S1lverEagle | 0:88e83d97a0ee | 20 | |
S1lverEagle | 0:88e83d97a0ee | 21 | // Biquad filter (See slide 14) |
S1lverEagle | 0:88e83d97a0ee | 22 | double biquad( double u, double &v1, double &v2, const double a1, const double a2, |
S1lverEagle | 0:88e83d97a0ee | 23 | const double b0, const double b1, const double b2 ) |
S1lverEagle | 0:88e83d97a0ee | 24 | { |
S1lverEagle | 1:64ec36ba6e76 | 25 | double v = u - a1*v1 - a2*v2; |
S1lverEagle | 1:64ec36ba6e76 | 26 | double y = b0*v + b1*v1 + b2*v2; |
S1lverEagle | 0:88e83d97a0ee | 27 | v2 = v1; |
S1lverEagle | 0:88e83d97a0ee | 28 | v1 = v; |
S1lverEagle | 0:88e83d97a0ee | 29 | return y; |
S1lverEagle | 0:88e83d97a0ee | 30 | } |
S1lverEagle | 0:88e83d97a0ee | 31 | |
S1lverEagle | 0:88e83d97a0ee | 32 | // Reusable PID controller with filter |
S1lverEagle | 1:64ec36ba6e76 | 33 | double PID( double e, const double Kp, const double Ki, const double Kd, double Ts, double &e_int, double &e_prev, double &f_v1, double &f_v2, const double f_a1, const double f_a2, const double f_b0, const double f_b1, const double f_b2) |
S1lverEagle | 0:88e83d97a0ee | 34 | { |
S1lverEagle | 0:88e83d97a0ee | 35 | // Derivative |
S1lverEagle | 1:64ec36ba6e76 | 36 | double e_der = (e - e_prev)/Ts; |
S1lverEagle | 0:88e83d97a0ee | 37 | e_der = biquad( e_der, f_v1, f_v2, f_a1, f_a2, f_b0, f_b1, f_b2 ); |
S1lverEagle | 0:88e83d97a0ee | 38 | e_prev = e; |
S1lverEagle | 0:88e83d97a0ee | 39 | // Integral |
S1lverEagle | 1:64ec36ba6e76 | 40 | e_int = e_int + Ts * e; |
S1lverEagle | 0:88e83d97a0ee | 41 | // PID |
S1lverEagle | 1:64ec36ba6e76 | 42 | return Kp * e + Ki * e_int + Kd * e_der; |
S1lverEagle | 0:88e83d97a0ee | 43 | } |
S1lverEagle | 0:88e83d97a0ee | 44 | |
S1lverEagle | 0:88e83d97a0ee | 45 | void m1_Controller() |
S1lverEagle | 0:88e83d97a0ee | 46 | { |
S1lverEagle | 0:88e83d97a0ee | 47 | double reference = potmeter1.read(); |
S1lverEagle | 1:64ec36ba6e76 | 48 | double position = 0.002991*encoder1.getPosition(); // Don’t use magic numbers! |
S1lverEagle | 1:64ec36ba6e76 | 49 | pos_1 = PID( reference - position, m1_Kp, m1_Ki, m1_Kd, m1_Ts, m1_err_int, m1_prev_err, m1_f_v1, m1_f_v2, m1_f_a1, m1_f_a2, m1_f_b0, m1_f_b1, m1_f_b2 ); |
S1lverEagle | 1:64ec36ba6e76 | 50 | if(pos_1 > 0) |
S1lverEagle | 0:88e83d97a0ee | 51 | dir_motor1 = 0; |
S1lverEagle | 0:88e83d97a0ee | 52 | else |
S1lverEagle | 0:88e83d97a0ee | 53 | dir_motor1 = 1; |
S1lverEagle | 0:88e83d97a0ee | 54 | |
S1lverEagle | 1:64ec36ba6e76 | 55 | pwm_motor1.write(abs(pos_1)); |
S1lverEagle | 0:88e83d97a0ee | 56 | } // Attach this function to a Ticker |
S1lverEagle | 0:88e83d97a0ee | 57 | |
S1lverEagle | 0:88e83d97a0ee | 58 | int main() |
S1lverEagle | 0:88e83d97a0ee | 59 | { |
S1lverEagle | 2:323606a75d64 | 60 | control_ticker.attach(&m1_Controller, 0.01); |
S1lverEagle | 2:323606a75d64 | 61 | |
S1lverEagle | 2:323606a75d64 | 62 | while(1){} |
S1lverEagle | 0:88e83d97a0ee | 63 | } |