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Dependencies: mbed
WheelControl/Wheel.h@10:acf5cb8d58d5, 2019-04-28 (annotated)
- Committer:
- mazdo25
- Date:
- Sun Apr 28 18:27:46 2019 +0000
- Revision:
- 10:acf5cb8d58d5
- Parent:
- 9:cefa177c1353
- Child:
- 11:78c645fb76cd
Brakes arent working;
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
mazdo25 | 5:f1613df66ceb | 1 | class Wheel |
mazdo25 | 5:f1613df66ceb | 2 | { |
mazdo25 | 5:f1613df66ceb | 3 | private: |
mazdo25 | 5:f1613df66ceb | 4 | |
mazdo25 | 5:f1613df66ceb | 5 | float distance; //distance traversed by wheel |
mazdo25 | 5:f1613df66ceb | 6 | float angularVelocity; |
mazdo25 | 10:acf5cb8d58d5 | 7 | int br; |
mazdo25 | 5:f1613df66ceb | 8 | |
mazdo25 | 10:acf5cb8d58d5 | 9 | float const static gain = 1.1f; //closed loop gain, (amount to amplify the difference) you have to tune this value |
mazdo25 | 5:f1613df66ceb | 10 | //but make sure its less than 1.5 otherwise you'll have a really sensitive motor |
mazdo25 | 5:f1613df66ceb | 11 | |
mazdo25 | 5:f1613df66ceb | 12 | PwmOut Mtr; //connect this pin to the motor driveboard pwm |
mazdo25 | 5:f1613df66ceb | 13 | DigitalOut direction; //connected to the direction pin of motor drive board |
mazdo25 | 5:f1613df66ceb | 14 | DigitalOut polarity; //connected to the bipolar of motor drive board. 0 = unipolar 1 = bipolar |
mazdo25 | 5:f1613df66ceb | 15 | |
mazdo25 | 5:f1613df66ceb | 16 | Ticker updater; |
mazdo25 | 5:f1613df66ceb | 17 | |
mazdo25 | 5:f1613df66ceb | 18 | Encoder* enc; |
mazdo25 | 5:f1613df66ceb | 19 | |
mazdo25 | 5:f1613df66ceb | 20 | PID controller; |
mazdo25 | 5:f1613df66ceb | 21 | |
mazdo25 | 5:f1613df66ceb | 22 | public: |
mazdo25 | 5:f1613df66ceb | 23 | |
mazdo25 | 8:5ed6685f6edd | 24 | float maxAngularVel; |
mazdo25 | 8:5ed6685f6edd | 25 | float minAngularVel; |
mazdo25 | 5:f1613df66ceb | 26 | |
mazdo25 | 5:f1613df66ceb | 27 | float static const wheelDiameter = 0.18; //used in calculation of Linear velocity i.e never |
mazdo25 | 5:f1613df66ceb | 28 | |
mazdo25 | 10:acf5cb8d58d5 | 29 | Wheel (Encoder* E, PinName M, PinName D, PinName Mode) : Mtr(M), direction(D), polarity(Mode), controller(gain,4.0f,0.00002f,0.0003f) |
mazdo25 | 5:f1613df66ceb | 30 | { |
mazdo25 | 5:f1613df66ceb | 31 | maxAngularVel = 0.0f; |
mazdo25 | 5:f1613df66ceb | 32 | enc = E; |
mazdo25 | 5:f1613df66ceb | 33 | polarity = 0; |
mazdo25 | 5:f1613df66ceb | 34 | direction = 0; |
mazdo25 | 5:f1613df66ceb | 35 | distance = 0; |
mazdo25 | 5:f1613df66ceb | 36 | Mtr.period_us(100); //frequency of 5KHz determine this constant value based on switching losses+frequency losses |
mazdo25 | 5:f1613df66ceb | 37 | //higher freq -> more switching losses lower freq -> more "capacitive losses" need to find a balance |
mazdo25 | 5:f1613df66ceb | 38 | Mtr.write(1); //start off on the turned off state |
mazdo25 | 5:f1613df66ceb | 39 | |
mazdo25 | 5:f1613df66ceb | 40 | updater.detach(); |
mazdo25 | 5:f1613df66ceb | 41 | |
mazdo25 | 5:f1613df66ceb | 42 | float *maxAVptr = &maxAngularVel; |
mazdo25 | 5:f1613df66ceb | 43 | float *minAVPtr = &minAngularVel; |
mazdo25 | 5:f1613df66ceb | 44 | controller.assignLimitAddress(maxAVptr,minAVPtr); |
mazdo25 | 5:f1613df66ceb | 45 | } |
mazdo25 | 5:f1613df66ceb | 46 | |
mazdo25 | 5:f1613df66ceb | 47 | void calculateAngularVelocity() //returns a float value which is the angular velocity of the WHEEL |
mazdo25 | 5:f1613df66ceb | 48 | { |
mazdo25 | 5:f1613df66ceb | 49 | float eTR = enc->encoderTickRate(); |
mazdo25 | 5:f1613df66ceb | 50 | angularVelocity = (eTR/256.0f)*2.0f*(float)PI; |
mazdo25 | 5:f1613df66ceb | 51 | } |
mazdo25 | 5:f1613df66ceb | 52 | |
mazdo25 | 5:f1613df66ceb | 53 | void setFrequency(int freq) //if you want to adjust the frequency |
mazdo25 | 5:f1613df66ceb | 54 | { |
mazdo25 | 5:f1613df66ceb | 55 | Mtr.period(1/freq); |
mazdo25 | 5:f1613df66ceb | 56 | } |
mazdo25 | 5:f1613df66ceb | 57 | |
mazdo25 | 5:f1613df66ceb | 58 | float returnAngularVelocity() //as it says |
mazdo25 | 5:f1613df66ceb | 59 | { |
mazdo25 | 5:f1613df66ceb | 60 | return angularVelocity; |
mazdo25 | 5:f1613df66ceb | 61 | } |
mazdo25 | 5:f1613df66ceb | 62 | |
mazdo25 | 5:f1613df66ceb | 63 | //only called once during initialization to calculate max angular velocity |
mazdo25 | 5:f1613df66ceb | 64 | //dir = direction, do opposite for each wheel just so your buggy doesn't move FORWARD but rather rotates |
mazdo25 | 5:f1613df66ceb | 65 | void init(int dir) |
mazdo25 | 5:f1613df66ceb | 66 | { |
mazdo25 | 5:f1613df66ceb | 67 | enc->startTimer(); |
mazdo25 | 5:f1613df66ceb | 68 | Mtr.write(0); //max speed |
mazdo25 | 5:f1613df66ceb | 69 | angularVelocity = 10.0f; |
mazdo25 | 5:f1613df66ceb | 70 | if (dir == 0) {direction = 0;} else {direction = 1;} |
mazdo25 | 10:acf5cb8d58d5 | 71 | updater.attach(callback(this, &Wheel::init2),0.6f); |
mazdo25 | 5:f1613df66ceb | 72 | } |
mazdo25 | 5:f1613df66ceb | 73 | |
mazdo25 | 5:f1613df66ceb | 74 | void init2(void) //used as a temporarily wait command for the wheel to spin to max |
mazdo25 | 5:f1613df66ceb | 75 | { |
mazdo25 | 6:477382219bcf | 76 | enc->startTimer(); |
mazdo25 | 5:f1613df66ceb | 77 | calculateAngularVelocity(); |
mazdo25 | 9:cefa177c1353 | 78 | maxAngularVel = 75.0f; |
mazdo25 | 5:f1613df66ceb | 79 | minAngularVel = -1.0f*maxAngularVel; |
mazdo25 | 5:f1613df66ceb | 80 | controller.setSetPoint(0.0f); |
mazdo25 | 5:f1613df66ceb | 81 | updater.attach(callback(this, &Wheel::wheelUpdates),0.0005f); |
mazdo25 | 5:f1613df66ceb | 82 | } |
mazdo25 | 5:f1613df66ceb | 83 | |
mazdo25 | 5:f1613df66ceb | 84 | void startController() |
mazdo25 | 5:f1613df66ceb | 85 | { |
mazdo25 | 5:f1613df66ceb | 86 | updater.attach(callback(this, &Wheel::wheelUpdates),0.01f); |
mazdo25 | 5:f1613df66ceb | 87 | } |
mazdo25 | 5:f1613df66ceb | 88 | |
mazdo25 | 5:f1613df66ceb | 89 | void stopController() |
mazdo25 | 5:f1613df66ceb | 90 | { |
mazdo25 | 5:f1613df66ceb | 91 | updater.detach(); |
mazdo25 | 5:f1613df66ceb | 92 | } |
mazdo25 | 5:f1613df66ceb | 93 | |
mazdo25 | 5:f1613df66ceb | 94 | void wheelUpdates(void) //sampling rate the ticker is attached I.E the wheel speed is updated everytime this function is called |
mazdo25 | 5:f1613df66ceb | 95 | { |
mazdo25 | 10:acf5cb8d58d5 | 96 | if (br == 0) { |
mazdo25 | 5:f1613df66ceb | 97 | calculateAngularVelocity(); |
mazdo25 | 8:5ed6685f6edd | 98 | //distance += angularVelocity*(wheelDiameter/2)*0.0005f; |
mazdo25 | 5:f1613df66ceb | 99 | float temp2 = controller.compute(angularVelocity); //another temporary value to store the computed angular velocity |
mazdo25 | 5:f1613df66ceb | 100 | if (temp2 < 0) {direction = 0;} else {direction = 1;} //change direction according to the computed value |
mazdo25 | 5:f1613df66ceb | 101 | Mtr.write((1.0f - abs(temp2))); //write the value as a pwm |
mazdo25 | 10:acf5cb8d58d5 | 102 | } |
mazdo25 | 10:acf5cb8d58d5 | 103 | else |
mazdo25 | 10:acf5cb8d58d5 | 104 | { |
mazdo25 | 10:acf5cb8d58d5 | 105 | return; |
mazdo25 | 10:acf5cb8d58d5 | 106 | } |
mazdo25 | 5:f1613df66ceb | 107 | } |
mazdo25 | 5:f1613df66ceb | 108 | |
mazdo25 | 5:f1613df66ceb | 109 | void adjustAngularVelocity(float W) // W = angular velocity you want, obviously putting a |w| value that is > max angular velocity will set dutcy cycle to max |
mazdo25 | 5:f1613df66ceb | 110 | { |
mazdo25 | 5:f1613df66ceb | 111 | controller.setSetPoint(W); |
mazdo25 | 5:f1613df66ceb | 112 | }; |
mazdo25 | 5:f1613df66ceb | 113 | |
mazdo25 | 5:f1613df66ceb | 114 | float getDistance(void) |
mazdo25 | 5:f1613df66ceb | 115 | { |
mazdo25 | 5:f1613df66ceb | 116 | return distance; //distance traversed by wheel |
mazdo25 | 5:f1613df66ceb | 117 | } |
mazdo25 | 5:f1613df66ceb | 118 | |
mazdo25 | 8:5ed6685f6edd | 119 | void stop() |
mazdo25 | 8:5ed6685f6edd | 120 | { |
mazdo25 | 8:5ed6685f6edd | 121 | controller.setSetPoint(0); |
mazdo25 | 8:5ed6685f6edd | 122 | } |
mazdo25 | 8:5ed6685f6edd | 123 | |
mazdo25 | 5:f1613df66ceb | 124 | float returnMaxAngularVel(void) |
mazdo25 | 5:f1613df66ceb | 125 | { |
mazdo25 | 5:f1613df66ceb | 126 | return maxAngularVel; |
mazdo25 | 5:f1613df66ceb | 127 | } |
mazdo25 | 5:f1613df66ceb | 128 | |
mazdo25 | 5:f1613df66ceb | 129 | float* returnMaxAVptr() |
mazdo25 | 5:f1613df66ceb | 130 | { |
mazdo25 | 5:f1613df66ceb | 131 | float *tempPTR = &maxAngularVel; |
mazdo25 | 5:f1613df66ceb | 132 | return tempPTR; |
mazdo25 | 5:f1613df66ceb | 133 | } |
mazdo25 | 5:f1613df66ceb | 134 | |
mazdo25 | 5:f1613df66ceb | 135 | float* returnMinAVptr() |
mazdo25 | 5:f1613df66ceb | 136 | { |
mazdo25 | 5:f1613df66ceb | 137 | float *tempPTR = &minAngularVel; |
mazdo25 | 5:f1613df66ceb | 138 | return tempPTR; |
mazdo25 | 5:f1613df66ceb | 139 | } |
mazdo25 | 5:f1613df66ceb | 140 | |
mazdo25 | 10:acf5cb8d58d5 | 141 | void setBR (int p) |
mazdo25 | 10:acf5cb8d58d5 | 142 | { |
mazdo25 | 10:acf5cb8d58d5 | 143 | br = p; |
mazdo25 | 10:acf5cb8d58d5 | 144 | } |
mazdo25 | 10:acf5cb8d58d5 | 145 | |
mazdo25 | 10:acf5cb8d58d5 | 146 | void brake() |
mazdo25 | 10:acf5cb8d58d5 | 147 | { |
mazdo25 | 10:acf5cb8d58d5 | 148 | direction = 0; |
mazdo25 | 10:acf5cb8d58d5 | 149 | Mtr.write(0); |
mazdo25 | 10:acf5cb8d58d5 | 150 | } |
mazdo25 | 10:acf5cb8d58d5 | 151 | |
mazdo25 | 5:f1613df66ceb | 152 | }; |