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Dependencies: HIDScope mbed MODSERIAL QEI
EMG.cpp
- Committer:
- john111222333
- Date:
- 2017-11-06
- Revision:
- 21:59431788a42d
- Parent:
- 16:a2a73d57d556
File content as of revision 21:59431788a42d:
#include "EMG.h"
// This is a class to set different emg sensors it gets the raw emg as input and returns the filterd envelope of the signal
EMG::EMG(PinName data) : _data(data) , MainsReject(0.940809296, -1.525271192, 0.940809296, 1.000000000, -1.525271192, 0.881618592) , // set the coeficients of all filters used in the code
Low_pass( 0.145323884, 0.290647768, 0.145323884, 1.000000000, -0.671029091, 0.252324626) , // all of the filters are objects of the class BiQuad.h
HiPass(0.914969144, -1.829938288, 0.914969144, 1.000000000, -1.822694925, 0.837181651) ,
LoPass( 0.003621682, 0.007243363, 0.003621682, 1.000000000, -1.822694925, 0.837181651)
{
cntr = 0;
}
double EMG::get_noise(){ // remove noise from the system (noise is conciderd 80Hz+)
return Low_pass.step(_data);
}
double EMG::get_notch(double data){ // remove 50Hz peak dew to all electrical network apliances
return MainsReject.step(data);
}
double EMG::get_DC(double data){ // remove DC offset from the signal (High pass filter above 10Hz)
return HiPass.step(data);
}
double EMG::get_absolute(double data){ //get the absolute value of the signal
return fabs(data);
}
double EMG::get_envelope(double data){ // return the envelope of the signal (low pass filter at 5Hz)
return LoPass.step(data);
}
double EMG::filter(){ // Aply all filters and absolute in series in order to get envelope of the EMG signal
if(cntr<=500)
{
cntr++;
return 0;
}
else
{
return get_envelope(get_absolute(get_DC(get_notch(get_noise()))));
}
}
double EMG::get_data(){
return _data;
}
