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Feedforward controller
Dependencies: MODSERIAL QEI mbed
Fork of Tut5_motor_controller by
main.cpp@4:983b50758735, 2017-10-06 (annotated)
- Committer:
- Arnoud113
- Date:
- Fri Oct 06 09:05:35 2017 +0000
- Revision:
- 4:983b50758735
- Parent:
- 3:cc3766838777
- Child:
- 5:6c16e9335262
shde;
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
Arnoud113 | 0:1816743ba8ba | 1 | #include "mbed.h" |
Arnoud113 | 0:1816743ba8ba | 2 | #include "QEI.h" |
Arnoud113 | 0:1816743ba8ba | 3 | #include "MODSERIAL.h" |
Arnoud113 | 0:1816743ba8ba | 4 | #include "math.h" |
Arnoud113 | 0:1816743ba8ba | 5 | |
Arnoud113 | 0:1816743ba8ba | 6 | |
Arnoud113 | 0:1816743ba8ba | 7 | |
Arnoud113 | 0:1816743ba8ba | 8 | DigitalOut gpo(D0); |
Arnoud113 | 3:cc3766838777 | 9 | DigitalOut ledb(LED_BLUE); |
Arnoud113 | 3:cc3766838777 | 10 | DigitalOut ledr(LED_RED); |
Arnoud113 | 3:cc3766838777 | 11 | DigitalOut ledg(LED_GREEN); |
Arnoud113 | 1:659489c32e75 | 12 | DigitalOut motor1DC(D7); |
Arnoud113 | 2:abd40da4a5e2 | 13 | PwmOut motor1PWM(D6); |
Arnoud113 | 0:1816743ba8ba | 14 | DigitalOut motor2DC(D4); |
Arnoud113 | 2:abd40da4a5e2 | 15 | PwmOut motor2PWM(D5); |
Arnoud113 | 0:1816743ba8ba | 16 | |
Arnoud113 | 3:cc3766838777 | 17 | AnalogIn potMeterIn1(A0); |
Arnoud113 | 4:983b50758735 | 18 | AnalogIn potMeterIn2(A1); |
Arnoud113 | 3:cc3766838777 | 19 | |
Arnoud113 | 0:1816743ba8ba | 20 | DigitalIn button1(D11); |
Arnoud113 | 0:1816743ba8ba | 21 | |
Arnoud113 | 0:1816743ba8ba | 22 | MODSERIAL pc(USBTX,USBRX); |
Arnoud113 | 4:983b50758735 | 23 | QEI Encoder(D12,D13,NC,32); |
Arnoud113 | 3:cc3766838777 | 24 | Ticker controller; |
Arnoud113 | 1:659489c32e75 | 25 | |
Arnoud113 | 0:1816743ba8ba | 26 | |
Arnoud113 | 0:1816743ba8ba | 27 | float GetReferenceVelocity() |
Arnoud113 | 0:1816743ba8ba | 28 | { |
Arnoud113 | 0:1816743ba8ba | 29 | // Returns reference velocity in rad/s. |
Arnoud113 | 0:1816743ba8ba | 30 | // Positive value means clockwise rotation. |
Arnoud113 | 0:1816743ba8ba | 31 | |
Arnoud113 | 0:1816743ba8ba | 32 | const float maxVelocity=8.4; // in rad/s of course! |
Arnoud113 | 0:1816743ba8ba | 33 | |
Arnoud113 | 0:1816743ba8ba | 34 | float referenceVelocity; // in rad/s |
Arnoud113 | 0:1816743ba8ba | 35 | |
Arnoud113 | 0:1816743ba8ba | 36 | if (button1) { |
Arnoud113 | 0:1816743ba8ba | 37 | // Clockwise rotation |
Arnoud113 | 3:cc3766838777 | 38 | referenceVelocity = potMeterIn1 * maxVelocity; |
Arnoud113 | 3:cc3766838777 | 39 | ledr = 1; |
Arnoud113 | 3:cc3766838777 | 40 | ledb = 0; |
Arnoud113 | 0:1816743ba8ba | 41 | } |
Arnoud113 | 0:1816743ba8ba | 42 | else { |
Arnoud113 | 0:1816743ba8ba | 43 | // Counterclockwise rotation |
Arnoud113 | 3:cc3766838777 | 44 | referenceVelocity = -1*potMeterIn1 * maxVelocity; |
Arnoud113 | 3:cc3766838777 | 45 | ledb = 1; |
Arnoud113 | 3:cc3766838777 | 46 | ledr = 0; |
Arnoud113 | 0:1816743ba8ba | 47 | } |
Arnoud113 | 0:1816743ba8ba | 48 | return referenceVelocity; |
Arnoud113 | 0:1816743ba8ba | 49 | } |
Arnoud113 | 0:1816743ba8ba | 50 | |
Arnoud113 | 0:1816743ba8ba | 51 | |
Arnoud113 | 0:1816743ba8ba | 52 | float FeedForwardControl(float &referenceVelocity) |
Arnoud113 | 0:1816743ba8ba | 53 | { |
Arnoud113 | 0:1816743ba8ba | 54 | // very simple linear feed-forward control |
Arnoud113 | 0:1816743ba8ba | 55 | const float MotorGain=8.4; // unit: (rad/s) / PWM |
Arnoud113 | 0:1816743ba8ba | 56 | float motorValue = referenceVelocity / MotorGain; |
Arnoud113 | 0:1816743ba8ba | 57 | return motorValue; |
Arnoud113 | 0:1816743ba8ba | 58 | } |
Arnoud113 | 0:1816743ba8ba | 59 | |
Arnoud113 | 4:983b50758735 | 60 | float GetReferencePosition() |
Arnoud113 | 4:983b50758735 | 61 | { |
Arnoud113 | 4:983b50758735 | 62 | int potmultiplier = 4200; // constant to multiply the pot 2 value with to get a reference position |
Arnoud113 | 4:983b50758735 | 63 | |
Arnoud113 | 4:983b50758735 | 64 | float referencePosition; |
Arnoud113 | 4:983b50758735 | 65 | referencePosition = potMeterIn2 * potmultiplier; |
Arnoud113 | 4:983b50758735 | 66 | return referencePosition; |
Arnoud113 | 4:983b50758735 | 67 | } |
Arnoud113 | 4:983b50758735 | 68 | |
Arnoud113 | 0:1816743ba8ba | 69 | void SetMotor1(float motorValue) |
Arnoud113 | 0:1816743ba8ba | 70 | { |
Arnoud113 | 0:1816743ba8ba | 71 | // Given -1<=motorValue<=1, this sets the PWM and direction |
Arnoud113 | 0:1816743ba8ba | 72 | // bits for motor 1. Positive value makes motor rotating |
Arnoud113 | 0:1816743ba8ba | 73 | // clockwise. motorValues outside range are truncated to |
Arnoud113 | 0:1816743ba8ba | 74 | // within range |
Arnoud113 | 1:659489c32e75 | 75 | if (motorValue >=0) motor1DC= 1; |
Arnoud113 | 0:1816743ba8ba | 76 | else motor1DC=0; |
Arnoud113 | 0:1816743ba8ba | 77 | if (fabs(motorValue)>1) motor1PWM = 1; |
Arnoud113 | 0:1816743ba8ba | 78 | else motor1PWM = fabs(motorValue); |
Arnoud113 | 0:1816743ba8ba | 79 | } |
Arnoud113 | 0:1816743ba8ba | 80 | |
Arnoud113 | 1:659489c32e75 | 81 | void MeasureAndControl(void) |
Arnoud113 | 1:659489c32e75 | 82 | { |
Arnoud113 | 1:659489c32e75 | 83 | float referenceVelocity = GetReferenceVelocity(); |
Arnoud113 | 4:983b50758735 | 84 | int referencePosition = GetReferencePosition(); |
Arnoud113 | 4:983b50758735 | 85 | int counts = Encoder.getPulses(); |
Arnoud113 | 4:983b50758735 | 86 | |
Arnoud113 | 4:983b50758735 | 87 | |
Arnoud113 | 4:983b50758735 | 88 | |
Arnoud113 | 4:983b50758735 | 89 | if(counts < referencePosition) |
Arnoud113 | 4:983b50758735 | 90 | { |
Arnoud113 | 4:983b50758735 | 91 | float motorValue = FeedForwardControl(referenceVelocity); |
Arnoud113 | 4:983b50758735 | 92 | SetMotor1(motorValue); |
Arnoud113 | 4:983b50758735 | 93 | } |
Arnoud113 | 4:983b50758735 | 94 | else |
Arnoud113 | 4:983b50758735 | 95 | { |
Arnoud113 | 4:983b50758735 | 96 | int b = -1; |
Arnoud113 | 4:983b50758735 | 97 | float motorValue = b * FeedForwardControl(referenceVelocity); |
Arnoud113 | 4:983b50758735 | 98 | SetMotor1(motorValue); |
Arnoud113 | 4:983b50758735 | 99 | } |
Arnoud113 | 4:983b50758735 | 100 | |
Arnoud113 | 1:659489c32e75 | 101 | } |
Arnoud113 | 1:659489c32e75 | 102 | |
Arnoud113 | 3:cc3766838777 | 103 | |
Arnoud113 | 3:cc3766838777 | 104 | |
Arnoud113 | 0:1816743ba8ba | 105 | int main() |
Arnoud113 | 0:1816743ba8ba | 106 | { |
Arnoud113 | 0:1816743ba8ba | 107 | pc.baud(115200); |
Arnoud113 | 2:abd40da4a5e2 | 108 | QEI Encoder(D12,D13,NC,32); |
Arnoud113 | 3:cc3766838777 | 109 | |
Arnoud113 | 3:cc3766838777 | 110 | ledr = 1; |
Arnoud113 | 3:cc3766838777 | 111 | ledb = 1; |
Arnoud113 | 3:cc3766838777 | 112 | ledg = 1; |
Arnoud113 | 0:1816743ba8ba | 113 | |
Arnoud113 | 2:abd40da4a5e2 | 114 | controller.attach(&MeasureAndControl, 0.1); |
Arnoud113 | 3:cc3766838777 | 115 | |
Arnoud113 | 1:659489c32e75 | 116 | while(1) |
Arnoud113 | 3:cc3766838777 | 117 | { |
Arnoud113 | 2:abd40da4a5e2 | 118 | int counts = Encoder.getPulses(); |
Arnoud113 | 2:abd40da4a5e2 | 119 | float rV = GetReferenceVelocity(); |
Arnoud113 | 2:abd40da4a5e2 | 120 | float mV = FeedForwardControl(rV); |
Arnoud113 | 4:983b50758735 | 121 | int rP = GetReferencePosition(); |
Arnoud113 | 2:abd40da4a5e2 | 122 | |
Arnoud113 | 4:983b50758735 | 123 | pc.printf("\r reference velocity: %f. Reference Position: %i Motor Value is: %f number of counts: %i\n",mV,rP,rV,counts); |
Arnoud113 | 2:abd40da4a5e2 | 124 | } |
Arnoud113 | 2:abd40da4a5e2 | 125 | |
Arnoud113 | 0:1816743ba8ba | 126 | } |
Arnoud113 | 0:1816743ba8ba | 127 | |
Arnoud113 | 0:1816743ba8ba | 128 |