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Dependencies: Encoder HIDScope mbed-dsp mbed
main.cpp@4:1a53b06eeb7f, 2014-09-29 (annotated)
- Committer:
- vsluiter
- Date:
- Mon Sep 29 21:07:58 2014 +0000
- Revision:
- 4:1a53b06eeb7f
- Parent:
- 2:5f5b229b004d
- Child:
- 5:06381e54b94a
Updated Encoder;
Who changed what in which revision?
| User | Revision | Line number | New contents of line | 
|---|---|---|---|
| vsluiter | 0:c9e647421e54 | 1 | #include "mbed.h" | 
| vsluiter | 0:c9e647421e54 | 2 | #include "encoder.h" | 
| vsluiter | 0:c9e647421e54 | 3 | #include "MODSERIAL.h" | 
| vsluiter | 0:c9e647421e54 | 4 | |
| vsluiter | 4:1a53b06eeb7f | 5 | #define K_P .01 | 
| vsluiter | 4:1a53b06eeb7f | 6 | //0.007//0.0184997836671646 //0.015 | 
| vsluiter | 4:1a53b06eeb7f | 7 | #define K_I 0.00 | 
| vsluiter | 4:1a53b06eeb7f | 8 | //.000824387821287097 //0 | 
| vsluiter | 4:1a53b06eeb7f | 9 | #define K_D .05 | 
| vsluiter | 4:1a53b06eeb7f | 10 | //0.01//.0972091946803081 //0.077 | 
| vsluiter | 1:5ac85aad9da4 | 11 | |
| vsluiter | 4:1a53b06eeb7f | 12 | #define POT_AVG 50 | 
| vsluiter | 0:c9e647421e54 | 13 | void coerce(float * in, float min, float max); | 
| vsluiter | 0:c9e647421e54 | 14 | float pid(float setpoint, float measurement); | 
| vsluiter | 1:5ac85aad9da4 | 15 | AnalogIn potmeter(PTC2); | 
| vsluiter | 0:c9e647421e54 | 16 | volatile bool looptimerflag; | 
| vsluiter | 1:5ac85aad9da4 | 17 | float potsamples[POT_AVG]; | 
| vsluiter | 0:c9e647421e54 | 18 | |
| vsluiter | 0:c9e647421e54 | 19 | void setlooptimerflag(void) | 
| vsluiter | 0:c9e647421e54 | 20 | { | 
| vsluiter | 0:c9e647421e54 | 21 | looptimerflag = true; | 
| vsluiter | 0:c9e647421e54 | 22 | } | 
| vsluiter | 0:c9e647421e54 | 23 | |
| vsluiter | 1:5ac85aad9da4 | 24 | void potAverager(void) | 
| vsluiter | 1:5ac85aad9da4 | 25 | { | 
| vsluiter | 1:5ac85aad9da4 | 26 | |
| vsluiter | 1:5ac85aad9da4 | 27 | static uint16_t sample_index = 0; | 
| vsluiter | 1:5ac85aad9da4 | 28 | float voltage = potmeter.read()-.5; | 
| vsluiter | 1:5ac85aad9da4 | 29 | |
| vsluiter | 1:5ac85aad9da4 | 30 | potsamples[sample_index] = voltage; | 
| vsluiter | 4:1a53b06eeb7f | 31 | |
| vsluiter | 1:5ac85aad9da4 | 32 | sample_index++; | 
| vsluiter | 1:5ac85aad9da4 | 33 | if(sample_index >= POT_AVG) | 
| vsluiter | 1:5ac85aad9da4 | 34 | sample_index = 0; | 
| vsluiter | 1:5ac85aad9da4 | 35 | } | 
| vsluiter | 1:5ac85aad9da4 | 36 | |
| vsluiter | 4:1a53b06eeb7f | 37 | void bubblesort(float arr[], int size) | 
| vsluiter | 4:1a53b06eeb7f | 38 | { | 
| vsluiter | 4:1a53b06eeb7f | 39 | int i,j; | 
| vsluiter | 4:1a53b06eeb7f | 40 | float temp; | 
| vsluiter | 4:1a53b06eeb7f | 41 | for ( i = 0 ; i <= (size/2)+1 ; i++ ) | 
| vsluiter | 4:1a53b06eeb7f | 42 | { | 
| vsluiter | 4:1a53b06eeb7f | 43 | for ( j = 0 ; j <= (size/2)+1 - i ; j++ ) | 
| vsluiter | 4:1a53b06eeb7f | 44 | { | 
| vsluiter | 4:1a53b06eeb7f | 45 | if ( arr[j] > arr[j + 1] ) | 
| vsluiter | 4:1a53b06eeb7f | 46 | { | 
| vsluiter | 4:1a53b06eeb7f | 47 | temp = arr[j] ; | 
| vsluiter | 4:1a53b06eeb7f | 48 | arr[j] = arr[j + 1] ; | 
| vsluiter | 4:1a53b06eeb7f | 49 | arr[j + 1] = temp ; | 
| vsluiter | 4:1a53b06eeb7f | 50 | } | 
| vsluiter | 4:1a53b06eeb7f | 51 | } | 
| vsluiter | 4:1a53b06eeb7f | 52 | } | 
| vsluiter | 4:1a53b06eeb7f | 53 | } | 
| vsluiter | 4:1a53b06eeb7f | 54 | |
| vsluiter | 4:1a53b06eeb7f | 55 | void quicksort(float own_array[], int low, int high) | 
| vsluiter | 4:1a53b06eeb7f | 56 | { | 
| vsluiter | 4:1a53b06eeb7f | 57 | int i = low; | 
| vsluiter | 4:1a53b06eeb7f | 58 | int j = high; | 
| vsluiter | 4:1a53b06eeb7f | 59 | int y = 0; | 
| vsluiter | 4:1a53b06eeb7f | 60 | /* compare value */ | 
| vsluiter | 4:1a53b06eeb7f | 61 | int z = own_array[(low + high) / 2]; | 
| vsluiter | 4:1a53b06eeb7f | 62 | /* partition */ | 
| vsluiter | 4:1a53b06eeb7f | 63 | do { | 
| vsluiter | 4:1a53b06eeb7f | 64 | /* find member above ... */ | 
| vsluiter | 4:1a53b06eeb7f | 65 | while(own_array[i] < z) i++; | 
| vsluiter | 4:1a53b06eeb7f | 66 | |
| vsluiter | 4:1a53b06eeb7f | 67 | /* find element below ... */ | 
| vsluiter | 4:1a53b06eeb7f | 68 | while(own_array[j] > z) j--; | 
| vsluiter | 4:1a53b06eeb7f | 69 | |
| vsluiter | 4:1a53b06eeb7f | 70 | if(i <= j) { | 
| vsluiter | 4:1a53b06eeb7f | 71 | /* swap two elements */ | 
| vsluiter | 4:1a53b06eeb7f | 72 | y = own_array[i]; | 
| vsluiter | 4:1a53b06eeb7f | 73 | own_array[i] = own_array[j]; | 
| vsluiter | 4:1a53b06eeb7f | 74 | own_array[j] = y; | 
| vsluiter | 4:1a53b06eeb7f | 75 | i++; | 
| vsluiter | 4:1a53b06eeb7f | 76 | j--; | 
| vsluiter | 4:1a53b06eeb7f | 77 | } | 
| vsluiter | 4:1a53b06eeb7f | 78 | } while(i <= j); | 
| vsluiter | 4:1a53b06eeb7f | 79 | |
| vsluiter | 4:1a53b06eeb7f | 80 | /* recurse */ | 
| vsluiter | 4:1a53b06eeb7f | 81 | if(low <= j) | 
| vsluiter | 4:1a53b06eeb7f | 82 | quicksort(own_array, low, j); | 
| vsluiter | 4:1a53b06eeb7f | 83 | |
| vsluiter | 4:1a53b06eeb7f | 84 | if(i <= high) | 
| vsluiter | 4:1a53b06eeb7f | 85 | quicksort(own_array, i, high); | 
| vsluiter | 4:1a53b06eeb7f | 86 | } | 
| vsluiter | 4:1a53b06eeb7f | 87 | |
| vsluiter | 1:5ac85aad9da4 | 88 | float getpotAverage(void) | 
| vsluiter | 1:5ac85aad9da4 | 89 | { | 
| vsluiter | 4:1a53b06eeb7f | 90 | //float own_array[POT_AVG]; | 
| vsluiter | 4:1a53b06eeb7f | 91 | //memcpy(own_array, potsamples, sizeof(own_array)); | 
| vsluiter | 4:1a53b06eeb7f | 92 | //bubblesort(own_array, POT_AVG-1); | 
| vsluiter | 4:1a53b06eeb7f | 93 | //return own_array[POT_AVG/2]; | 
| vsluiter | 4:1a53b06eeb7f | 94 | uint16_t valuecounter; | 
| vsluiter | 4:1a53b06eeb7f | 95 | float sum = 0; | 
| vsluiter | 4:1a53b06eeb7f | 96 | for(valuecounter = 0 ; valuecounter < POT_AVG ; valuecounter++) | 
| vsluiter | 4:1a53b06eeb7f | 97 | { | 
| vsluiter | 4:1a53b06eeb7f | 98 | sum += potsamples[valuecounter]; | 
| vsluiter | 4:1a53b06eeb7f | 99 | } | 
| vsluiter | 1:5ac85aad9da4 | 100 | return sum / (POT_AVG*1.); | 
| vsluiter | 1:5ac85aad9da4 | 101 | } | 
| vsluiter | 1:5ac85aad9da4 | 102 | |
| vsluiter | 4:1a53b06eeb7f | 103 | int main() | 
| vsluiter | 4:1a53b06eeb7f | 104 | { | 
| vsluiter | 0:c9e647421e54 | 105 | Encoder motor1(PTD0,PTC9); | 
| vsluiter | 1:5ac85aad9da4 | 106 | Ticker potaverage; | 
| vsluiter | 0:c9e647421e54 | 107 | MODSERIAL pc(USBTX,USBRX); | 
| vsluiter | 0:c9e647421e54 | 108 | PwmOut pwm_motor(PTA12); | 
| vsluiter | 0:c9e647421e54 | 109 | DigitalOut motordir(PTD3); | 
| vsluiter | 1:5ac85aad9da4 | 110 | potaverage.attach(potAverager,0.002); | 
| vsluiter | 4:1a53b06eeb7f | 111 | pc.baud(921600); | 
| vsluiter | 0:c9e647421e54 | 112 | Ticker looptimer; | 
| vsluiter | 4:1a53b06eeb7f | 113 | looptimer.attach(setlooptimerflag,0.01); | 
| vsluiter | 4:1a53b06eeb7f | 114 | pc.printf("bla"); | 
| vsluiter | 0:c9e647421e54 | 115 | while(1) { | 
| vsluiter | 1:5ac85aad9da4 | 116 | float setpoint; | 
| vsluiter | 0:c9e647421e54 | 117 | float new_pwm; | 
| vsluiter | 0:c9e647421e54 | 118 | while(!looptimerflag); | 
| vsluiter | 0:c9e647421e54 | 119 | looptimerflag = false; | 
| vsluiter | 1:5ac85aad9da4 | 120 | setpoint = (getpotAverage())*2000; | 
| vsluiter | 2:5f5b229b004d | 121 | //new_pwm = (setpoint - motor1.getPosition())*.001; | 
| vsluiter | 2:5f5b229b004d | 122 | new_pwm = pid(setpoint, motor1.getPosition()); | 
| vsluiter | 0:c9e647421e54 | 123 | coerce(&new_pwm, -1,1); | 
| vsluiter | 4:1a53b06eeb7f | 124 | pc.printf("%f %f %f 0\n", setpoint/2000.+0.5, motor1.getPosition()/2000.+.5,new_pwm/2.+0.5); | 
| vsluiter | 0:c9e647421e54 | 125 | if(new_pwm > 0) | 
| vsluiter | 0:c9e647421e54 | 126 | motordir = 1; | 
| vsluiter | 0:c9e647421e54 | 127 | else | 
| vsluiter | 4:1a53b06eeb7f | 128 | motordir = 0; | 
| vsluiter | 0:c9e647421e54 | 129 | pwm_motor.write(abs(new_pwm)); | 
| vsluiter | 0:c9e647421e54 | 130 | } | 
| vsluiter | 0:c9e647421e54 | 131 | } | 
| vsluiter | 0:c9e647421e54 | 132 | |
| vsluiter | 1:5ac85aad9da4 | 133 | |
| vsluiter | 1:5ac85aad9da4 | 134 | //coerces value 'in' to min or max when exceeding those values | 
| vsluiter | 1:5ac85aad9da4 | 135 | //if you'd like to understand the statement below take a google for | 
| vsluiter | 1:5ac85aad9da4 | 136 | //'ternary operators'. | 
| vsluiter | 0:c9e647421e54 | 137 | void coerce(float * in, float min, float max) | 
| vsluiter | 0:c9e647421e54 | 138 | { | 
| vsluiter | 4:1a53b06eeb7f | 139 | *in > min ? *in < max? : *in = max: *in = min; | 
| vsluiter | 0:c9e647421e54 | 140 | } | 
| vsluiter | 0:c9e647421e54 | 141 | |
| vsluiter | 0:c9e647421e54 | 142 | |
| vsluiter | 0:c9e647421e54 | 143 | float pid(float setpoint, float measurement) | 
| vsluiter | 0:c9e647421e54 | 144 | { | 
| vsluiter | 4:1a53b06eeb7f | 145 | float error; | 
| vsluiter | 4:1a53b06eeb7f | 146 | static float prev_error = 0; | 
| vsluiter | 4:1a53b06eeb7f | 147 | float out_p = 0; | 
| vsluiter | 4:1a53b06eeb7f | 148 | static float out_i = 0; | 
| vsluiter | 4:1a53b06eeb7f | 149 | float out_d = 0; | 
| vsluiter | 4:1a53b06eeb7f | 150 | error = setpoint-measurement; | 
| vsluiter | 4:1a53b06eeb7f | 151 | out_p = error*K_P; | 
| vsluiter | 4:1a53b06eeb7f | 152 | out_i += error*K_I; | 
| vsluiter | 4:1a53b06eeb7f | 153 | out_d = (error-prev_error)*K_D; | 
| vsluiter | 4:1a53b06eeb7f | 154 | coerce(&out_i,-0.5,0.5); | 
| vsluiter | 4:1a53b06eeb7f | 155 | prev_error = error; | 
| vsluiter | 4:1a53b06eeb7f | 156 | return out_p + out_i + out_d; | 
| vsluiter | 0:c9e647421e54 | 157 | } | 
| vsluiter | 0:c9e647421e54 | 158 |