![](/media/cache/img/default_profile.jpg.50x50_q85.jpg)
Control up to two motors using filtered EMG signals and a PID controller
Dependencies: FastPWM HIDScope MODSERIAL QEI Matrix biquadFilter controller errorFetch mbed motorConfig refGen MatrixMath inverseKinematics
Fork of Minor_test_serial by
main.cpp@23:917179f72762, 2017-10-06 (annotated)
- Committer:
- tvlogman
- Date:
- Fri Oct 06 12:03:26 2017 +0000
- Revision:
- 23:917179f72762
- Parent:
- 22:2e473e9798c0
- Child:
- 24:672abc3f02b7
Fixed the I-action bit: now I action is based on the position error multiplied by Ts added to the previous I error instead of the Ts multiplied by total I error.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
vsluiter | 0:c8f15874531b | 1 | #include "mbed.h" |
vsluiter | 0:c8f15874531b | 2 | #include "MODSERIAL.h" |
tvlogman | 8:0067469c3389 | 3 | #include "HIDScope.h" |
tvlogman | 9:5f0e796c9489 | 4 | #include "QEI.h" |
tvlogman | 15:b76b8cff4d8f | 5 | #include "FastPWM.h" |
tvlogman | 15:b76b8cff4d8f | 6 | |
tvlogman | 15:b76b8cff4d8f | 7 | enum robotStates {KILLED, ACTIVE}; |
tvlogman | 15:b76b8cff4d8f | 8 | robotStates currentState = KILLED; |
tvlogman | 8:0067469c3389 | 9 | |
tvlogman | 12:0462757e1ed2 | 10 | QEI Encoder(D12,D13,NC,64, QEI::X4_ENCODING); |
tvlogman | 10:e23cbcdde7e3 | 11 | MODSERIAL pc(USBTX, USBRX); |
tvlogman | 8:0067469c3389 | 12 | |
tvlogman | 14:664870b5d153 | 13 | // Defining outputs |
tvlogman | 22:2e473e9798c0 | 14 | |
tvlogman | 22:2e473e9798c0 | 15 | // Leds can be used to indicate status |
tvlogman | 22:2e473e9798c0 | 16 | DigitalOut ledG(LED_GREEN); |
tvlogman | 22:2e473e9798c0 | 17 | DigitalOut ledR(LED_RED); |
tvlogman | 22:2e473e9798c0 | 18 | DigitalOut ledB(LED_BLUE); |
tvlogman | 22:2e473e9798c0 | 19 | |
tvlogman | 13:83e3672b24ee | 20 | DigitalOut motor1_direction(D4); |
tvlogman | 13:83e3672b24ee | 21 | PwmOut motor1_pwm(D5); |
tvlogman | 14:664870b5d153 | 22 | |
tvlogman | 14:664870b5d153 | 23 | // Defining inputs |
tvlogman | 14:664870b5d153 | 24 | InterruptIn sw2(SW2); |
tvlogman | 15:b76b8cff4d8f | 25 | InterruptIn sw3(SW3); |
tvlogman | 16:27430afe663e | 26 | InterruptIn button1(D2); |
tvlogman | 21:d266d1e503ce | 27 | AnalogIn pot1(A0); |
tvlogman | 21:d266d1e503ce | 28 | AnalogIn pot2(A1); |
tvlogman | 15:b76b8cff4d8f | 29 | |
tvlogman | 16:27430afe663e | 30 | // PWM settings |
tvlogman | 16:27430afe663e | 31 | float pwmPeriod = 1.0/5000.0; |
tvlogman | 16:27430afe663e | 32 | int frequency_pwm = 10000; //10kHz PWM |
tvlogman | 14:664870b5d153 | 33 | |
tvlogman | 16:27430afe663e | 34 | volatile float x; |
tvlogman | 16:27430afe663e | 35 | volatile float x_prev =0; |
tvlogman | 16:27430afe663e | 36 | volatile float y; // filtered 'output' of ReadAnalogInAndFilter |
tvlogman | 14:664870b5d153 | 37 | |
tvlogman | 17:616ce7bc1f96 | 38 | // Initializing encoder |
tvlogman | 10:e23cbcdde7e3 | 39 | Ticker encoderTicker; |
tvlogman | 19:f08b5cd2b7ce | 40 | Ticker controllerTicker; |
tvlogman | 10:e23cbcdde7e3 | 41 | volatile int counts = 0; |
tvlogman | 12:0462757e1ed2 | 42 | volatile float revs = 0.00; |
tvlogman | 7:1bffab95fc5f | 43 | |
tvlogman | 19:f08b5cd2b7ce | 44 | // MOTOR CONTROL PART |
tvlogman | 20:4ce3fb543a45 | 45 | bool m1_direction = false; |
tvlogman | 23:917179f72762 | 46 | int posRevRange = 2; // describes the ends of the position range in complete motor output shaft revolutions in both directions |
tvlogman | 21:d266d1e503ce | 47 | const float maxAngle = 2*3.14*posRevRange; // max angle in radians |
tvlogman | 22:2e473e9798c0 | 48 | const float Ts = 0.1; |
tvlogman | 20:4ce3fb543a45 | 49 | |
tvlogman | 21:d266d1e503ce | 50 | // Function getReferencePosition returns reference angle within range |
tvlogman | 21:d266d1e503ce | 51 | float getReferencePosition(){ |
tvlogman | 19:f08b5cd2b7ce | 52 | double r; |
tvlogman | 20:4ce3fb543a45 | 53 | if(m1_direction == false){ |
tvlogman | 19:f08b5cd2b7ce | 54 | // Clockwise rotation yields positive reference |
tvlogman | 21:d266d1e503ce | 55 | r = maxAngle*pot1.read(); |
tvlogman | 19:f08b5cd2b7ce | 56 | } |
tvlogman | 20:4ce3fb543a45 | 57 | if(m1_direction == true){ |
tvlogman | 19:f08b5cd2b7ce | 58 | // Counterclockwise rotation yields negative reference |
tvlogman | 21:d266d1e503ce | 59 | r = -1*maxAngle*pot1.read(); |
tvlogman | 19:f08b5cd2b7ce | 60 | } |
tvlogman | 19:f08b5cd2b7ce | 61 | return r; |
tvlogman | 19:f08b5cd2b7ce | 62 | } |
tvlogman | 19:f08b5cd2b7ce | 63 | |
tvlogman | 22:2e473e9798c0 | 64 | // Initializing position and integral errors |
tvlogman | 22:2e473e9798c0 | 65 | float posError = 0; |
tvlogman | 22:2e473e9798c0 | 66 | float integralError = 0; |
tvlogman | 22:2e473e9798c0 | 67 | float totalError = posError + integralError; |
tvlogman | 22:2e473e9798c0 | 68 | |
tvlogman | 21:d266d1e503ce | 69 | // readEncoder reads counts and revs and logs results to serial window |
tvlogman | 22:2e473e9798c0 | 70 | void getError(float &posError, float &integralError){ |
tvlogman | 21:d266d1e503ce | 71 | counts = Encoder.getPulses(); |
tvlogman | 21:d266d1e503ce | 72 | double motor1Position = 2*3.14*(counts/(131*64.0f)); |
tvlogman | 21:d266d1e503ce | 73 | pc.printf("%0.2f revolutions \r\n", motor1Position); |
tvlogman | 22:2e473e9798c0 | 74 | posError = getReferencePosition() - motor1Position; |
tvlogman | 22:2e473e9798c0 | 75 | |
tvlogman | 23:917179f72762 | 76 | integralError = integralError + Ts*posError; |
tvlogman | 22:2e473e9798c0 | 77 | totalError = posError + integralError; |
tvlogman | 22:2e473e9798c0 | 78 | pc.printf("Error is %0.2f \r \n", totalError); |
tvlogman | 21:d266d1e503ce | 79 | } |
tvlogman | 21:d266d1e503ce | 80 | |
tvlogman | 21:d266d1e503ce | 81 | // motorController sets a motorValue based on the position error. Sign indicates direction and magnitude indicates speed. Right now this is a simple feedforward |
tvlogman | 22:2e473e9798c0 | 82 | float motorController(float posError, float integralError){ |
tvlogman | 21:d266d1e503ce | 83 | float k_p = 5*pot2.read(); // use potmeter 2 to adjust k_p within range 0 to 1 |
tvlogman | 23:917179f72762 | 84 | float k_i = 0.001; // How do I pick a reasonable value for k_i? |
tvlogman | 22:2e473e9798c0 | 85 | double motorValue = (posError*k_p)/maxAngle + 0.35 + k_i*integralError; // motorValue is the normalized voltage applied to motor magnitude pin between -1 and 1 added 0.35 as motorvalue of 0.35 does nothing |
tvlogman | 19:f08b5cd2b7ce | 86 | return motorValue; |
tvlogman | 10:e23cbcdde7e3 | 87 | } |
tvlogman | 14:664870b5d153 | 88 | |
tvlogman | 19:f08b5cd2b7ce | 89 | // setMotor1 sets the direction and magnitude pins of motor1 depending on the given motorValue. Negative motorValue means clockwise rotation |
tvlogman | 19:f08b5cd2b7ce | 90 | void setMotor1(float motorValue){ |
tvlogman | 19:f08b5cd2b7ce | 91 | switch(currentState){ |
tvlogman | 19:f08b5cd2b7ce | 92 | case KILLED: |
tvlogman | 19:f08b5cd2b7ce | 93 | motor1_pwm.write(0.0); |
tvlogman | 22:2e473e9798c0 | 94 | ledR = 0; |
tvlogman | 22:2e473e9798c0 | 95 | ledG = 1; |
tvlogman | 22:2e473e9798c0 | 96 | ledB = 1; |
tvlogman | 19:f08b5cd2b7ce | 97 | break; |
tvlogman | 19:f08b5cd2b7ce | 98 | case ACTIVE: |
tvlogman | 19:f08b5cd2b7ce | 99 | // Set motor direction |
tvlogman | 19:f08b5cd2b7ce | 100 | if (motorValue >=0){ |
tvlogman | 19:f08b5cd2b7ce | 101 | motor1_direction = 0; |
tvlogman | 19:f08b5cd2b7ce | 102 | } |
tvlogman | 19:f08b5cd2b7ce | 103 | else { |
tvlogman | 19:f08b5cd2b7ce | 104 | motor1_direction = 1; |
tvlogman | 19:f08b5cd2b7ce | 105 | } |
tvlogman | 19:f08b5cd2b7ce | 106 | // Set motor speed |
tvlogman | 19:f08b5cd2b7ce | 107 | if (fabs(motorValue)>1){ |
tvlogman | 19:f08b5cd2b7ce | 108 | motor1_pwm = 1; |
tvlogman | 19:f08b5cd2b7ce | 109 | } |
tvlogman | 19:f08b5cd2b7ce | 110 | else { |
tvlogman | 19:f08b5cd2b7ce | 111 | motor1_pwm.write(fabs(motorValue)); |
tvlogman | 22:2e473e9798c0 | 112 | } |
tvlogman | 22:2e473e9798c0 | 113 | ledR = 1; |
tvlogman | 22:2e473e9798c0 | 114 | ledG = 1; |
tvlogman | 22:2e473e9798c0 | 115 | ledB = 0; |
tvlogman | 19:f08b5cd2b7ce | 116 | break; |
tvlogman | 19:f08b5cd2b7ce | 117 | } |
tvlogman | 19:f08b5cd2b7ce | 118 | } |
tvlogman | 19:f08b5cd2b7ce | 119 | |
tvlogman | 19:f08b5cd2b7ce | 120 | void measureAndControl(){ |
tvlogman | 22:2e473e9798c0 | 121 | getError(posError, integralError); |
tvlogman | 22:2e473e9798c0 | 122 | float motorValue = motorController(posError, integralError); |
tvlogman | 21:d266d1e503ce | 123 | pc.printf("Position error is %.2f \r \n", posError); |
tvlogman | 22:2e473e9798c0 | 124 | pc.printf("Total error is %.2f \r \n", totalError); |
tvlogman | 22:2e473e9798c0 | 125 | pc.printf("Integral error is %2f", integralError); |
tvlogman | 22:2e473e9798c0 | 126 | //pc.printf("Motorvalue is %.2f \r \n", motorValue); |
tvlogman | 22:2e473e9798c0 | 127 | //pc.printf("Motor direction is %d \r \n", motor1_direction); |
tvlogman | 19:f08b5cd2b7ce | 128 | setMotor1(motorValue); |
tvlogman | 19:f08b5cd2b7ce | 129 | } |
tvlogman | 19:f08b5cd2b7ce | 130 | |
tvlogman | 14:664870b5d153 | 131 | void killSwitch(){ |
tvlogman | 15:b76b8cff4d8f | 132 | pc.printf("Motors turned off"); |
tvlogman | 15:b76b8cff4d8f | 133 | currentState = KILLED; |
tvlogman | 14:664870b5d153 | 134 | } |
tvlogman | 14:664870b5d153 | 135 | |
tvlogman | 15:b76b8cff4d8f | 136 | void turnMotorsOn(){ |
tvlogman | 15:b76b8cff4d8f | 137 | pc.printf("Motors turned on"); |
tvlogman | 15:b76b8cff4d8f | 138 | currentState = ACTIVE; |
tvlogman | 15:b76b8cff4d8f | 139 | } |
tvlogman | 15:b76b8cff4d8f | 140 | |
tvlogman | 15:b76b8cff4d8f | 141 | |
tvlogman | 14:664870b5d153 | 142 | void M1switchDirection(){ |
tvlogman | 20:4ce3fb543a45 | 143 | m1_direction = !m1_direction; |
tvlogman | 22:2e473e9798c0 | 144 | pc.printf("Switched direction!"); |
tvlogman | 14:664870b5d153 | 145 | } |
vsluiter | 0:c8f15874531b | 146 | |
tvlogman | 21:d266d1e503ce | 147 | |
tvlogman | 19:f08b5cd2b7ce | 148 | |
vsluiter | 0:c8f15874531b | 149 | int main() |
tvlogman | 10:e23cbcdde7e3 | 150 | { |
tvlogman | 19:f08b5cd2b7ce | 151 | pc.printf("Main function"); |
tvlogman | 20:4ce3fb543a45 | 152 | motor1_direction = 0; // False = clockwise rotation |
tvlogman | 13:83e3672b24ee | 153 | motor1_pwm.period(pwmPeriod);//T=1/f |
tvlogman | 14:664870b5d153 | 154 | sw2.fall(&killSwitch); |
tvlogman | 15:b76b8cff4d8f | 155 | sw3.fall(&turnMotorsOn); |
tvlogman | 16:27430afe663e | 156 | button1.rise(&M1switchDirection); |
vsluiter | 0:c8f15874531b | 157 | pc.baud(115200); |
tvlogman | 22:2e473e9798c0 | 158 | controllerTicker.attach(measureAndControl, Ts); |
tvlogman | 15:b76b8cff4d8f | 159 | |
tvlogman | 19:f08b5cd2b7ce | 160 | pc.printf("Encoder ticker attached and baudrate set"); |
vsluiter | 0:c8f15874531b | 161 | } |
tvlogman | 7:1bffab95fc5f | 162 |