Pascal van Baardwijk / Mbed 2 deprecated EMGfilter

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Dependencies:   HIDScope biquadFilter mbed

main.cpp@7:a928724ef731, 2016-10-27 (annotated)

Committer:
pbaardwijk
Date:
Thu Oct 27 09:57:26 2016 +0000
Revision:
7:a928724ef731
Parent:
6:da06585e106c
Child:
8:dc0858fead9f
Child:
9:81637351bbd1
Working awesome super duper EMG filter

Who changed what in which revision?

UserRevisionLine numberNew contents of line
pbaardwijk 0:ae0bec143f2d 1 #include "mbed.h"
pbaardwijk 0:ae0bec143f2d 2 #include "BiQuad.h"
pbaardwijk 0:ae0bec143f2d 3 #include "HIDScope.h"
pbaardwijk 0:ae0bec143f2d 4 //Enum with states
pbaardwijk 0:ae0bec143f2d 5 enum states {STATE_DEFAULT , STATE_CALIBRATION, STATE_RUN};
pbaardwijk 0:ae0bec143f2d 6
pbaardwijk 0:ae0bec143f2d 7 //Variable called 'state'
pbaardwijk 0:ae0bec143f2d 8 states state = STATE_DEFAULT;
pbaardwijk 0:ae0bec143f2d 9
pbaardwijk 0:ae0bec143f2d 10 //Creating two scope channels
pbaardwijk 7:a928724ef731 11 HIDScope scope(4);
pbaardwijk 6:da06585e106c 12
pbaardwijk 0:ae0bec143f2d 13 //Notch filter
pbaardwijk 0:ae0bec143f2d 14 BiQuadChain notch_50;
pbaardwijk 7:a928724ef731 15 BiQuad bq3( 0.98116526140, 0.00000000044, 0.98116526140, 0.00000000043, 0.95391787621);
pbaardwijk 7:a928724ef731 16 BiQuad bq4( 0.97224232015, 0.00000000043, 0.97224232015, -0.04036799459, 0.97670000725);
pbaardwijk 7:a928724ef731 17 BiQuad bq5( 1.00000000000, 0.00000000044, 1.00000000000, 0.04036799547, 0.9767000072);
pbaardwijk 0:ae0bec143f2d 18
pbaardwijk 0:ae0bec143f2d 19 //High pass filter
pbaardwijk 0:ae0bec143f2d 20 BiQuadChain high_pass;
pbaardwijk 7:a928724ef731 21 BiQuad bq6( 0.80254782780,-1.60509565560, 0.80254782780, -1.58011656361, 0.63006219630);
pbaardwijk 7:a928724ef731 22 BiQuad bq7( 0.90006571973,-1.80013143945, 0.900065719734, -1.77213098592, 0.8281459694);
pbaardwijk 7:a928724ef731 23 //BiQuad bq8( 0.92490714701,-1.84981429401, 0.92490714701, -1.90032503529, 0.9352152620);
pbaardwijk 0:ae0bec143f2d 24
pbaardwijk 5:02b3550e1ff0 25 //Low pass filter
pbaardwijk 5:02b3550e1ff0 26 BiQuadChain low_pass;
pbaardwijk 7:a928724ef731 27 BiQuad bq9( 0.00801840797, 0.01603681594, 0.00801840797,-1.65212256130, 0.68416767240);
pbaardwijk 7:a928724ef731 28 BiQuad bq10( 0.00836524486, 0.01673048973, 0.00836524486,-1.72511837232, 0.75857933411);
pbaardwijk 7:a928724ef731 29 BiQuad bq11( 0.00905039996, 0.01810079992, 0.00905039996,-1.86807725180, 0.9043110909);
pbaardwijk 0:ae0bec143f2d 30 //Ticker
pbaardwijk 0:ae0bec143f2d 31 Ticker emgSampleTicker;
pbaardwijk 0:ae0bec143f2d 32
pbaardwijk 0:ae0bec143f2d 33 //Timeout to change state after 5 seconds
pbaardwijk 0:ae0bec143f2d 34 Timeout change_state;
pbaardwijk 0:ae0bec143f2d 35
pbaardwijk 1:7fb4a74d33ff 36 //Timeout to change state after 15 seconds
pbaardwijk 0:ae0bec143f2d 37 Timeout change_state2;
pbaardwijk 0:ae0bec143f2d 38
pbaardwijk 1:7fb4a74d33ff 39 //LED
pbaardwijk 1:7fb4a74d33ff 40 DigitalOut led(LED_RED);
pbaardwijk 1:7fb4a74d33ff 41
pbaardwijk 0:ae0bec143f2d 42 //Emg input
pbaardwijk 0:ae0bec143f2d 43 AnalogIn emg0( A0 );
pbaardwijk 0:ae0bec143f2d 44 AnalogIn emg1( A1 );
pbaardwijk 0:ae0bec143f2d 45 AnalogIn emg2( A2 );
pbaardwijk 0:ae0bec143f2d 46
pbaardwijk 0:ae0bec143f2d 47 bool go_emgSample;
pbaardwijk 0:ae0bec143f2d 48 bool go_find_minmax;
pbaardwijk 0:ae0bec143f2d 49 double emg_sample[3];
pbaardwijk 6:da06585e106c 50 double emg_low_passed_200[3];
pbaardwijk 0:ae0bec143f2d 51 double emg_notch[3];
pbaardwijk 0:ae0bec143f2d 52 double emg_high_passed[3];
pbaardwijk 5:02b3550e1ff0 53 double emg_low_passed[3];
pbaardwijk 0:ae0bec143f2d 54 double min_emg[3];
pbaardwijk 0:ae0bec143f2d 55 double max_emg[3];
pbaardwijk 0:ae0bec143f2d 56
pbaardwijk 7:a928724ef731 57 const int n = 100;
pbaardwijk 0:ae0bec143f2d 58 int counter = 0;
pbaardwijk 0:ae0bec143f2d 59 double RMSArray0[n] = {0};
pbaardwijk 0:ae0bec143f2d 60 double RMSArray1[n] = {0};
pbaardwijk 0:ae0bec143f2d 61 double RMSArray2[n] = {0};
pbaardwijk 0:ae0bec143f2d 62 double RMS0;
pbaardwijk 0:ae0bec143f2d 63 double RMS1;
pbaardwijk 0:ae0bec143f2d 64 double RMS2;
pbaardwijk 0:ae0bec143f2d 65 double SumRMS0;
pbaardwijk 0:ae0bec143f2d 66 double SumRMS1;
pbaardwijk 0:ae0bec143f2d 67 double SumRMS2;
pbaardwijk 0:ae0bec143f2d 68
pbaardwijk 0:ae0bec143f2d 69 double input_force0;
pbaardwijk 0:ae0bec143f2d 70 double input_force1;
pbaardwijk 0:ae0bec143f2d 71 double input_force2;
pbaardwijk 0:ae0bec143f2d 72
pbaardwijk 0:ae0bec143f2d 73 //count for emg min max
pbaardwijk 0:ae0bec143f2d 74 int start_calibration = 0;
pbaardwijk 0:ae0bec143f2d 75
pbaardwijk 0:ae0bec143f2d 76 void emgSample() {
pbaardwijk 0:ae0bec143f2d 77 go_emgSample = true;
pbaardwijk 0:ae0bec143f2d 78 }
pbaardwijk 0:ae0bec143f2d 79
pbaardwijk 0:ae0bec143f2d 80 void calibrate() {
pbaardwijk 0:ae0bec143f2d 81 state = STATE_CALIBRATION;
pbaardwijk 1:7fb4a74d33ff 82 led.write(0);
pbaardwijk 0:ae0bec143f2d 83 }
pbaardwijk 0:ae0bec143f2d 84
pbaardwijk 0:ae0bec143f2d 85 void run() {
pbaardwijk 0:ae0bec143f2d 86 state = STATE_RUN;
pbaardwijk 1:7fb4a74d33ff 87 led.write(1);
pbaardwijk 0:ae0bec143f2d 88 }
pbaardwijk 0:ae0bec143f2d 89
pbaardwijk 0:ae0bec143f2d 90 void EMG_filter();
pbaardwijk 0:ae0bec143f2d 91
pbaardwijk 0:ae0bec143f2d 92 int main() {
pbaardwijk 0:ae0bec143f2d 93 //combine biquads in biquad chains for notch/high- low-pass filters
pbaardwijk 6:da06585e106c 94 notch_50.add( &bq3 ).add( &bq4 ).add( &bq5 );
pbaardwijk 7:a928724ef731 95 high_pass.add( &bq6 ).add( &bq7 );
pbaardwijk 6:da06585e106c 96 low_pass.add( &bq9 ).add( &bq10 ).add( &bq11 );
pbaardwijk 1:7fb4a74d33ff 97 led.write(1);
pbaardwijk 0:ae0bec143f2d 98
pbaardwijk 0:ae0bec143f2d 99 change_state.attach( &calibrate,5);
pbaardwijk 1:7fb4a74d33ff 100 change_state2.attach( &run,15);
pbaardwijk 7:a928724ef731 101 emgSampleTicker.attach( &emgSample, 0.005); //200Hz
pbaardwijk 0:ae0bec143f2d 102 while( true ){
pbaardwijk 0:ae0bec143f2d 103 if(go_emgSample == true){
pbaardwijk 0:ae0bec143f2d 104 EMG_filter();
pbaardwijk 0:ae0bec143f2d 105 }
pbaardwijk 0:ae0bec143f2d 106 }
pbaardwijk 0:ae0bec143f2d 107 }
pbaardwijk 0:ae0bec143f2d 108
pbaardwijk 0:ae0bec143f2d 109
pbaardwijk 0:ae0bec143f2d 110 void EMG_filter() {
pbaardwijk 0:ae0bec143f2d 111 if(go_emgSample == true){
pbaardwijk 0:ae0bec143f2d 112 //read the emg signal
pbaardwijk 0:ae0bec143f2d 113 emg_sample[0] = emg0.read();
pbaardwijk 0:ae0bec143f2d 114 emg_sample[1] = emg1.read();
pbaardwijk 0:ae0bec143f2d 115 emg_sample[2] = emg2.read();
pbaardwijk 0:ae0bec143f2d 116
pbaardwijk 7:a928724ef731 117 //filter out the 50Hz components with a notch filter
pbaardwijk 7:a928724ef731 118 emg_notch[0] = notch_50.step(emg_sample[0]);
pbaardwijk 0:ae0bec143f2d 119
pbaardwijk 7:a928724ef731 120 //high pass the signal (removing motion artifacts and offset)
pbaardwijk 7:a928724ef731 121 emg_high_passed[0] = high_pass.step(emg_notch[0]);
pbaardwijk 5:02b3550e1ff0 122
pbaardwijk 7:a928724ef731 123 //low pass the rectified emg signal
pbaardwijk 7:a928724ef731 124 emg_low_passed[0] = low_pass.step(fabs(emg_high_passed[0]));
pbaardwijk 0:ae0bec143f2d 125
pbaardwijk 0:ae0bec143f2d 126 //Calculating RMS
pbaardwijk 0:ae0bec143f2d 127 SumRMS0 -= pow(RMSArray0[counter],2);
pbaardwijk 0:ae0bec143f2d 128 SumRMS1 -= pow(RMSArray1[counter],2);
pbaardwijk 0:ae0bec143f2d 129 SumRMS2 -= pow(RMSArray2[counter],2);
pbaardwijk 0:ae0bec143f2d 130
pbaardwijk 0:ae0bec143f2d 131 RMSArray0[counter] = emg_high_passed[0];
pbaardwijk 0:ae0bec143f2d 132 RMSArray1[counter] = emg_high_passed[1];
pbaardwijk 0:ae0bec143f2d 133 RMSArray2[counter] = emg_high_passed[2];
pbaardwijk 0:ae0bec143f2d 134
pbaardwijk 0:ae0bec143f2d 135 SumRMS0 += pow(RMSArray0[counter],2);
pbaardwijk 0:ae0bec143f2d 136 SumRMS1 += pow(RMSArray1[counter],2);
pbaardwijk 0:ae0bec143f2d 137 SumRMS2 += pow(RMSArray2[counter],2);
pbaardwijk 0:ae0bec143f2d 138
pbaardwijk 0:ae0bec143f2d 139 counter++;
pbaardwijk 0:ae0bec143f2d 140 if (counter == n){
pbaardwijk 0:ae0bec143f2d 141 counter = 0;
pbaardwijk 0:ae0bec143f2d 142 }
pbaardwijk 0:ae0bec143f2d 143
pbaardwijk 0:ae0bec143f2d 144 RMS0 = sqrt(SumRMS0/n);
pbaardwijk 0:ae0bec143f2d 145 RMS1 = sqrt(SumRMS1/n);
pbaardwijk 0:ae0bec143f2d 146 RMS2 = sqrt(SumRMS2/n);
pbaardwijk 0:ae0bec143f2d 147
pbaardwijk 0:ae0bec143f2d 148 //Calculating min value and max value of emg signal
pbaardwijk 0:ae0bec143f2d 149 if(state == STATE_CALIBRATION)
pbaardwijk 0:ae0bec143f2d 150 {
pbaardwijk 0:ae0bec143f2d 151 if (start_calibration == 0) {
pbaardwijk 0:ae0bec143f2d 152 min_emg[0] = RMS0;
pbaardwijk 0:ae0bec143f2d 153 max_emg[0] = RMS0;
pbaardwijk 0:ae0bec143f2d 154 min_emg[1] = RMS1;
pbaardwijk 0:ae0bec143f2d 155 max_emg[1] = RMS1;
pbaardwijk 0:ae0bec143f2d 156 min_emg[2] = RMS2;
pbaardwijk 0:ae0bec143f2d 157 max_emg[2] = RMS2;
pbaardwijk 0:ae0bec143f2d 158 start_calibration++;
pbaardwijk 0:ae0bec143f2d 159 }
pbaardwijk 0:ae0bec143f2d 160 else {
pbaardwijk 0:ae0bec143f2d 161 //finding min and max of emg0
pbaardwijk 0:ae0bec143f2d 162 if (RMS0 < min_emg[0]) {
pbaardwijk 0:ae0bec143f2d 163 min_emg[0] = RMS0;
pbaardwijk 0:ae0bec143f2d 164 }
pbaardwijk 0:ae0bec143f2d 165 else if (RMS0 > max_emg[0]) {
pbaardwijk 0:ae0bec143f2d 166 max_emg[0] = RMS0;
pbaardwijk 0:ae0bec143f2d 167 }
pbaardwijk 0:ae0bec143f2d 168
pbaardwijk 0:ae0bec143f2d 169 //finding min and max of emg1
pbaardwijk 0:ae0bec143f2d 170 if (RMS1 < min_emg[1]) {
pbaardwijk 0:ae0bec143f2d 171 min_emg[1] = RMS1;
pbaardwijk 0:ae0bec143f2d 172 }
pbaardwijk 0:ae0bec143f2d 173 else if (RMS1 > max_emg[1]) {
pbaardwijk 0:ae0bec143f2d 174 max_emg[1] = RMS1;
pbaardwijk 0:ae0bec143f2d 175 }
pbaardwijk 0:ae0bec143f2d 176
pbaardwijk 0:ae0bec143f2d 177 //finding min and max of emg2
pbaardwijk 0:ae0bec143f2d 178 if (RMS2 < min_emg[2]) {
pbaardwijk 0:ae0bec143f2d 179 min_emg[2] = RMS2;
pbaardwijk 0:ae0bec143f2d 180 }
pbaardwijk 0:ae0bec143f2d 181 else if (RMS2 > max_emg[2]) {
pbaardwijk 0:ae0bec143f2d 182 max_emg[2] = RMS2;
pbaardwijk 0:ae0bec143f2d 183 }
pbaardwijk 0:ae0bec143f2d 184 }
pbaardwijk 0:ae0bec143f2d 185 }
pbaardwijk 0:ae0bec143f2d 186
pbaardwijk 0:ae0bec143f2d 187 //calculating input_forces for controller
pbaardwijk 0:ae0bec143f2d 188 input_force0 = (RMS0 - min_emg[0])/(max_emg[0]-min_emg[0]);
pbaardwijk 0:ae0bec143f2d 189 input_force1 = (RMS1 - min_emg[1])/(max_emg[1]-min_emg[1]);
pbaardwijk 0:ae0bec143f2d 190 input_force2 = (RMS2 - min_emg[2])/(max_emg[2]-min_emg[2]);
pbaardwijk 0:ae0bec143f2d 191
pbaardwijk 0:ae0bec143f2d 192 //Send scope data
pbaardwijk 0:ae0bec143f2d 193 scope.set(0,emg_sample[0]);
pbaardwijk 7:a928724ef731 194 scope.set(1,emg_notch[0]);
pbaardwijk 7:a928724ef731 195 scope.set(2,emg_high_passed[0]);
pbaardwijk 7:a928724ef731 196 scope.set(3,emg_low_passed[0]);
pbaardwijk 7:a928724ef731 197 //scope.set(2,emg_low_passed[0]);
pbaardwijk 0:ae0bec143f2d 198 //scope.set(3,input_force2);
pbaardwijk 0:ae0bec143f2d 199 scope.send();
pbaardwijk 0:ae0bec143f2d 200
pbaardwijk 0:ae0bec143f2d 201 go_emgSample = false;
pbaardwijk 0:ae0bec143f2d 202 }
pbaardwijk 0:ae0bec143f2d 203 }
pbaardwijk 0:ae0bec143f2d 204