Janet Huisman / Mbed 2 deprecated EMG_Original_converter_code

Dependencies:   HIDScope MODSERIAL biquadFilter mbed

Fork of EMG_converter_code by K K

main.cpp@1:9913e3886643, 2015-10-23 (annotated)

Committer:
Technical_Muffin
Date:
Fri Oct 23 08:36:59 2015 +0000
Revision:
1:9913e3886643
Parent:
0:1883d922ada8
Child:
2:83659da3e5fe
EMG code adapted to calibrate signal to patients specific amplitude

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 0:1883d922ada8 9 /*The biquad filters required to transform the EMG signal into an usable signal*/
Technical_Muffin 0:1883d922ada8 10 biquadFilter filterhigh1(-1.1430, 0.4128, 0.6389, -1.2779, 0.6389);
Technical_Muffin 0:1883d922ada8 11 biquadFilter filterlow1(1.9556, 0.9565, 0.9780, 1.9561, 0.9780);
Technical_Muffin 0:1883d922ada8 12 biquadFilter notch(-1.1978e-16, 0.9561, 0.9780, -1.1978e-16, 0.9780);
Technical_Muffin 0:1883d922ada8 13 biquadFilter filterlow2(-1.9645, 0.9651, 1.5515e-4, 3.1030e-4, 1.5515e-4);
Technical_Muffin 1:9913e3886643 14 double emg_value;
Technical_Muffin 1:9913e3886643 15 double signalpart1;
Technical_Muffin 1:9913e3886643 16 double signalpart2;
Technical_Muffin 1:9913e3886643 17 double signalpart3;
Technical_Muffin 1:9913e3886643 18 double signalpart4;
Technical_Muffin 1:9913e3886643 19 double signalfinal;
Technical_Muffin 1:9913e3886643 20
Technical_Muffin 0:1883d922ada8 21 /*
Technical_Muffin 0:1883d922ada8 22 */
Technical_Muffin 0:1883d922ada8 23 void filter()
Technical_Muffin 0:1883d922ada8 24 {
Technical_Muffin 1:9913e3886643 25 emg_value = emg.read();//read the emg value from the elektrodes
Technical_Muffin 1:9913e3886643 26 signalpart1 = filterhigh1.step(emg_value);//Highpass filter for removing offset and artifacts
Technical_Muffin 1:9913e3886643 27 signalpart2 = abs(signalpart1);//rectify the filtered signal
Technical_Muffin 1:9913e3886643 28 signalpart3 = filterlow1.step(signalpart2);//low pass filter to envelope the emg
Technical_Muffin 1:9913e3886643 29 signalpart4 = notch.step(signalpart3);//notch filter to remove 50Hz signal
Technical_Muffin 1:9913e3886643 30 signalfinal = filterlow2.step(signalpart4);//2nd low pass filter to envelope the emg
Technical_Muffin 1:9913e3886643 31 scope.set(0,emg_value);//set emg signal to scope in channel 1
Technical_Muffin 1:9913e3886643 32 scope.set(1,signalfinal);//set filtered signal to scope in channel 2
Technical_Muffin 1:9913e3886643 33 scope.send();//send the signals to the scope
Technical_Muffin 0:1883d922ada8 34 }
Technical_Muffin 0:1883d922ada8 35
Technical_Muffin 0:1883d922ada8 36 int main()
Technical_Muffin 0:1883d922ada8 37 {
Technical_Muffin 1:9913e3886643 38 int caldone=0;
Technical_Muffin 1:9913e3886643 39 double maxValue = 0;//define the max value to start with
Technical_Muffin 1:9913e3886643 40 while(1){
Technical_Muffin 1:9913e3886643 41 while(PTC6){//as long as the button is pressed record the emg signal
Technical_Muffin 1:9913e3886643 42 double signalmeasure=emg.read();//read the emg values to check for max
Technical_Muffin 1:9913e3886643 43 if(signalmeasure > maxValue){
Technical_Muffin 1:9913e3886643 44 maxValue = signalmeasure;
Technical_Muffin 1:9913e3886643 45 }
Technical_Muffin 1:9913e3886643 46 caldone=1;
Technical_Muffin 1:9913e3886643 47 }
Technical_Muffin 1:9913e3886643 48 double maxcal=maxValue;
Technical_Muffin 1:9913e3886643 49 if(caldone==1){
Technical_Muffin 1:9913e3886643 50 sample_timer.attach(&filter, 0.002);//continously execute the EMG reader and filter
Technical_Muffin 1:9913e3886643 51 double onoffsignal=signalfinal/maxcal;//divide the emg signal by the max EMG to calibrate the signal per person
Technical_Muffin 1:9913e3886643 52 }
Technical_Muffin 1:9913e3886643 53 }
Technical_Muffin 0:1883d922ada8 54 }