Roos Wijngaarden / Mbed 2 deprecated EMG_Realtime_Filter

Measures EMG signal, filters them and puts on a led

Dependencies:   HIDScope MODSERIAL Math MovingAverage biquadFilter mbed

Fork of EMG by Tom Tom

main.cpp@21:30a33a4aa868, 2018-10-26 (annotated)

Committer:
Roooos
Date:
Fri Oct 26 11:03:48 2018 +0000
Revision:
21:30a33a4aa868
Parent:
20:97059009a491 
EMG Realtime Filter Measures EMG from Left and Right Bicep, Filters them and puts a led on.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
vsluiter 0:32bb76391d89 1 #include "mbed.h"
vsluiter 11:ce72ec658a95 2 #include "HIDScope.h"
Roooos 21:30a33a4aa868 3 #include "BiQuad.h"
Roooos 21:30a33a4aa868 4 #include "MovingAverage.h"
Roooos 21:30a33a4aa868 5 #include "MODSERIAL.h"
Roooos 21:30a33a4aa868 6 #include "math.h"
Roooos 21:30a33a4aa868 7 #define NSAMPLE 200
Roooos 21:30a33a4aa868 8
vsluiter 0:32bb76391d89 9
vsluiter 4:8b298dfada81 10 //Define objects
Roooos 21:30a33a4aa868 11 AnalogIn emg0( A0 ); //Biceps Left
Roooos 21:30a33a4aa868 12 AnalogIn emg1( A1 ); //Biceps Right
Roooos 21:30a33a4aa868 13 InterruptIn button(PTC6);
Roooos 21:30a33a4aa868 14 InterruptIn button2(PTA4);
tomlankhorst 14:f83354387756 15 Ticker sample_timer;
Roooos 21:30a33a4aa868 16
Roooos 21:30a33a4aa868 17 //Ticker driving_timer;
Roooos 21:30a33a4aa868 18 HIDScope scope( 4 ); //Number of Channels
Roooos 21:30a33a4aa868 19 DigitalOut led1(LED_GREEN);
Roooos 21:30a33a4aa868 20 DigitalOut led2(LED_BLUE);
Roooos 21:30a33a4aa868 21 DigitalOut led3(LED_RED);
Roooos 21:30a33a4aa868 22 MovingAverage <double>Movag_LB(NSAMPLE,0.0); //Make Moving Average, Define NSAMPLE above
Roooos 21:30a33a4aa868 23 MovingAverage <double>Movag_RB(NSAMPLE,0.0);
Roooos 21:30a33a4aa868 24
Roooos 21:30a33a4aa868 25 MODSERIAL pc(USBTX, USBRX);
Roooos 21:30a33a4aa868 26
Roooos 21:30a33a4aa868 27 volatile bool BicepLeft = false;
Roooos 21:30a33a4aa868 28 volatile bool BicepRight = false;
vsluiter 2:e314bb3b2d99 29
Roooos 21:30a33a4aa868 30
Roooos 21:30a33a4aa868 31 //Make Biquad filters Left(a0, a1, a2, b1, b2)
Roooos 21:30a33a4aa868 32 BiQuadChain bqc1; //chain voor High Pass en Notch
Roooos 21:30a33a4aa868 33 BiQuad bq1(0.39131200825291007, -0.7826240165058201, 0.39131200825291007, -0.36950493743858204, 0.1957430955730582); //High Pass Filter
Roooos 21:30a33a4aa868 34 BiQuad bq2(9.91104e-01, -1.60364e+00, 9.91104e-01, -1.60364e+00, 9.82207e-01); //Notch Filter
Roooos 21:30a33a4aa868 35 BiQuad bq3(0.00044924972004654657, 0.0008984994400930931, 0.00044924972004654657, -1.6169385656964415, 0.6187355645766276); //Low Pass Filter
Roooos 21:30a33a4aa868 36
Roooos 21:30a33a4aa868 37 //Make Biquad filters Right
Roooos 21:30a33a4aa868 38 BiQuadChain bqc2; //chain voor High Pass en Notch
Roooos 21:30a33a4aa868 39 BiQuad bq4(0.39131200825291007, -0.7826240165058201, 0.39131200825291007, -0.36950493743858204, 0.1957430955730582); //High Pass Filter
Roooos 21:30a33a4aa868 40 BiQuad bq5(9.91104e-01, -1.60364e+00, 9.91104e-01, -1.60364e+00, 9.82207e-01); //Notch Filter
Roooos 21:30a33a4aa868 41
Roooos 21:30a33a4aa868 42 //Function to read samples and filter and send to HIDScope
tomlankhorst 14:f83354387756 43 void sample()
vsluiter 2:e314bb3b2d99 44 {
Roooos 21:30a33a4aa868 45 //Filter Left Bicep
Roooos 21:30a33a4aa868 46 double LB_Filter_1 = bqc1.step(emg0.read()); //High Pass + Notch
Roooos 21:30a33a4aa868 47 double LB_Rectify = fabs(LB_Filter_1); //Rectify Signal
Roooos 21:30a33a4aa868 48 //double Filtered_emg_1 = bq3.step(LB_Rectify); //Low Pass
Roooos 21:30a33a4aa868 49 Movag_LB.Insert(LB_Rectify);
Roooos 21:30a33a4aa868 50 double LB_Out = Movag_LB.GetAverage();
Roooos 21:30a33a4aa868 51
Roooos 21:30a33a4aa868 52 //Filter Right Bicep
Roooos 21:30a33a4aa868 53 double RB_Filter_1 = bqc2.step(emg1.read()); //High Pass + Notch
Roooos 21:30a33a4aa868 54 double RB_Rectify = fabs(RB_Filter_1); //Rectify Signal
Roooos 21:30a33a4aa868 55 //double Filtered_emg_1 = bq3.step(RB_Rectify); //Low Pass
Roooos 21:30a33a4aa868 56 Movag_RB.Insert(RB_Rectify);
Roooos 21:30a33a4aa868 57 double RB_Out = Movag_RB.GetAverage();
Roooos 21:30a33a4aa868 58
Roooos 21:30a33a4aa868 59 scope.set(0, emg0.read() ); //Raw EMG signal left bicep
Roooos 21:30a33a4aa868 60 scope.set(1, LB_Out); // Filtered EMG signal left bicep
Roooos 21:30a33a4aa868 61 scope.set(2, emg1.read()); //Raw EMG signal right bicep
Roooos 21:30a33a4aa868 62 scope.set(3, RB_Out); //Filtered EMG signal right bicep
Roooos 21:30a33a4aa868 63
vsluiter 11:ce72ec658a95 64 scope.send();
Roooos 21:30a33a4aa868 65
Roooos 21:30a33a4aa868 66 if (LB_Out > ThresholdLeft) {
Roooos 21:30a33a4aa868 67 led1 = 0;
Roooos 21:30a33a4aa868 68 BicepLeft = true;
Roooos 21:30a33a4aa868 69 }
Roooos 21:30a33a4aa868 70 else {
Roooos 21:30a33a4aa868 71 led1 = 1;
Roooos 21:30a33a4aa868 72 BicepLeft = false;
Roooos 21:30a33a4aa868 73 }
Roooos 21:30a33a4aa868 74 if (RB_Out > ThresholdRight) {
Roooos 21:30a33a4aa868 75 led2 = 0;
Roooos 21:30a33a4aa868 76 BicepRight = true;
Roooos 21:30a33a4aa868 77 }
Roooos 21:30a33a4aa868 78 else {
Roooos 21:30a33a4aa868 79 led2 = 1;
Roooos 21:30a33a4aa868 80 BicepRight = false;
Roooos 21:30a33a4aa868 81 }
vsluiter 2:e314bb3b2d99 82 }
vsluiter 0:32bb76391d89 83
Roooos 21:30a33a4aa868 84
vsluiter 0:32bb76391d89 85 int main()
tomlankhorst 19:2bf824669684 86 {
Roooos 21:30a33a4aa868 87 bqc1.add( &bq1 ).add( &bq2 ); //make BiQuadChain
Roooos 21:30a33a4aa868 88 bqc2.add( &bq4 ).add( &bq5 ); //make BiQuadChain
Roooos 21:30a33a4aa868 89 sample_timer.attach(&sample, 0.002); //read samples at 500 Hz
tomlankhorst 15:0da764eea774 90 while(1) {}
Roooos 21:30a33a4aa868 91 }