Gerlinde van de Haar / Mbed 2 deprecated EMG_converter_code

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Dependencies:   HIDScope MODSERIAL QEI biquadFilter mbed

Fork of EMG_converter_code by K K

main.cpp@2:83659da3e5fe, 2015-10-26 (annotated)

Committer:
Technical_Muffin
Date:
Mon Oct 26 13:22:32 2015 +0000
Revision:
2:83659da3e5fe
Parent:
1:9913e3886643
Child:
3:a69f041108d4
pre-commit before just testing the emg read without normalising the values

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Technical_Muffin 0:1883d922ada8 1 #include "mbed.h"
Technical_Muffin 0:1883d922ada8 2 #include "HIDScope.h"
Technical_Muffin 0:1883d922ada8 3 #include "biquadFilter.h" // Require the HIDScope library
Technical_Muffin 0:1883d922ada8 4
Technical_Muffin 0:1883d922ada8 5 //Define objects
Technical_Muffin 0:1883d922ada8 6 AnalogIn emg(A0); //Analog of EMG input
Technical_Muffin 0:1883d922ada8 7 Ticker sample_timer;
Technical_Muffin 0:1883d922ada8 8 HIDScope scope(2); // Instantize a 2-channel HIDScope object
Technical_Muffin 2:83659da3e5fe 9 DigitalIn button1(PTA4);//test button for starting motor 1
Technical_Muffin 2:83659da3e5fe 10 DigitalOut led1(LED_RED);
Technical_Muffin 0:1883d922ada8 11 /*The biquad filters required to transform the EMG signal into an usable signal*/
Technical_Muffin 0:1883d922ada8 12 biquadFilter filterhigh1(-1.1430, 0.4128, 0.6389, -1.2779, 0.6389);
Technical_Muffin 0:1883d922ada8 13 biquadFilter filterlow1(1.9556, 0.9565, 0.9780, 1.9561, 0.9780);
Technical_Muffin 0:1883d922ada8 14 biquadFilter notch(-1.1978e-16, 0.9561, 0.9780, -1.1978e-16, 0.9780);
Technical_Muffin 0:1883d922ada8 15 biquadFilter filterlow2(-1.9645, 0.9651, 1.5515e-4, 3.1030e-4, 1.5515e-4);
Technical_Muffin 1:9913e3886643 16 double emg_value;
Technical_Muffin 1:9913e3886643 17 double signalpart1;
Technical_Muffin 1:9913e3886643 18 double signalpart2;
Technical_Muffin 1:9913e3886643 19 double signalpart3;
Technical_Muffin 1:9913e3886643 20 double signalpart4;
Technical_Muffin 1:9913e3886643 21 double signalfinal;
Technical_Muffin 2:83659da3e5fe 22 double onoffsignal;
Technical_Muffin 2:83659da3e5fe 23 double maxcal=1;
Technical_Muffin 0:1883d922ada8 24 /*
Technical_Muffin 0:1883d922ada8 25 */
Technical_Muffin 2:83659da3e5fe 26 void filter(){
Technical_Muffin 1:9913e3886643 27 emg_value = emg.read();//read the emg value from the elektrodes
Technical_Muffin 1:9913e3886643 28 signalpart1 = filterhigh1.step(emg_value);//Highpass filter for removing offset and artifacts
Technical_Muffin 1:9913e3886643 29 signalpart2 = abs(signalpart1);//rectify the filtered signal
Technical_Muffin 1:9913e3886643 30 signalpart3 = filterlow1.step(signalpart2);//low pass filter to envelope the emg
Technical_Muffin 1:9913e3886643 31 signalpart4 = notch.step(signalpart3);//notch filter to remove 50Hz signal
Technical_Muffin 1:9913e3886643 32 signalfinal = filterlow2.step(signalpart4);//2nd low pass filter to envelope the emg
Technical_Muffin 2:83659da3e5fe 33 onoffsignal=signalfinal/maxcal;//divide the emg signal by the max EMG to calibrate the signal per person
Technical_Muffin 1:9913e3886643 34 scope.set(0,emg_value);//set emg signal to scope in channel 1
Technical_Muffin 2:83659da3e5fe 35 scope.set(1,onoffsignal);//set filtered signal to scope in channel 2
Technical_Muffin 1:9913e3886643 36 scope.send();//send the signals to the scope
Technical_Muffin 0:1883d922ada8 37 }
Technical_Muffin 2:83659da3e5fe 38 double normalcal(){
Technical_Muffin 2:83659da3e5fe 39 double signalmeasure =emg.read();
Technical_Muffin 2:83659da3e5fe 40 if (signalmeasure > maxcal){
Technical_Muffin 2:83659da3e5fe 41 signalmeasure = maxcal;
Technical_Muffin 2:83659da3e5fe 42 }
Technical_Muffin 2:83659da3e5fe 43 return maxcal;
Technical_Muffin 2:83659da3e5fe 44 }
Technical_Muffin 2:83659da3e5fe 45 const int button_pressed = 0;
Technical_Muffin 2:83659da3e5fe 46 bool caldone =0;
Technical_Muffin 0:1883d922ada8 47 int main()
Technical_Muffin 0:1883d922ada8 48 {
Technical_Muffin 2:83659da3e5fe 49
Technical_Muffin 2:83659da3e5fe 50 if(button1.read() == button_pressed){//as long as the button is pressed record the emg signal
Technical_Muffin 2:83659da3e5fe 51 led1.write(!led1.read());
Technical_Muffin 2:83659da3e5fe 52 } /* double signalmeasure=emg.read();//read the emg values to check for max
Technical_Muffin 2:83659da3e5fe 53 if(signalmeasure > maxcal){
Technical_Muffin 2:83659da3e5fe 54 maxcal = signalmeasure;
Technical_Muffin 1:9913e3886643 55 }
Technical_Muffin 2:83659da3e5fe 56 caldone=1; */
Technical_Muffin 2:83659da3e5fe 57
Technical_Muffin 1:9913e3886643 58 if(caldone==1){
Technical_Muffin 1:9913e3886643 59 sample_timer.attach(&filter, 0.002);//continously execute the EMG reader and filter
Technical_Muffin 2:83659da3e5fe 60 }
Technical_Muffin 0:1883d922ada8 61 }