BioRobotics Group 3 / Mbed 2 deprecated Moving-average

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Dependencies:   HIDScope MODSERIAL mbed

Fork of Signal Filter by BioRobotics Group 3

main.cpp@8:a1ea1bf49944, 2015-10-19 (annotated)

Committer:
fredwsl
Date:
Mon Oct 19 08:36:31 2015 +0000
Revision:
8:a1ea1bf49944
Parent:
7:7493a0c5c6aa 
Working low pass filter

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Peasofcake 0:c8a6e00fbdc3 1 #include "mbed.h"
Peasofcake 1:f6110f80fa45 2 #include "MODSERIAL.h"
Peasofcake 2:e30dbfec6d1e 3 #include "math.h"
Peasofcake 1:f6110f80fa45 4 #include "HIDScope.h"
Peasofcake 2:e30dbfec6d1e 5
Peasofcake 2:e30dbfec6d1e 6
fredwsl 8:a1ea1bf49944 7 AnalogIn EMG(A1);
Peasofcake 1:f6110f80fa45 8 MODSERIAL pc(USBTX, USBRX);
Peasofcake 0:c8a6e00fbdc3 9
Peasofcake 2:e30dbfec6d1e 10 //const int baudrate = 115200;
Peasofcake 1:f6110f80fa45 11 //const int ms_wait = 100;
Peasofcake 0:c8a6e00fbdc3 12
Peasofcake 1:f6110f80fa45 13 // Define the HIDScope and Ticker objects
Peasofcake 2:e30dbfec6d1e 14 HIDScope scope(1);
Peasofcake 2:e30dbfec6d1e 15 Ticker scopeTimer;
Peasofcake 2:e30dbfec6d1e 16
fredwsl 6:c20a8c0f90ed 17 // Define moving average variables
fredwsl 8:a1ea1bf49944 18 const int N = 125;
fredwsl 6:c20a8c0f90ed 19 double a;
Peasofcake 2:e30dbfec6d1e 20
Peasofcake 2:e30dbfec6d1e 21 // Define the storage variables and filter coeicients for two filters
Peasofcake 2:e30dbfec6d1e 22 double f1_v1 = 0, f1_v2 = 0, f2_v1 = 0, f2_v2 = 0;
fredwsl 8:a1ea1bf49944 23 const double f1_a1 = -1.822694925196308, f1_a2 = 0.837181651256022, f1_b0 = 0.914969144113083, f1_b1 = -1.829938288226165, f1_b2 = 0.914969144113083;
fredwsl 8:a1ea1bf49944 24 const double f2_a1 = -1.964460580205232, f2_a2 = 0.965081173899135, f2_b0 = 0.000155148423475721, f2_b1 = 0.000310296846951441, f2_b2 = 0.000155148423475721;
Peasofcake 2:e30dbfec6d1e 25
Peasofcake 3:04f3cca82b22 26 double biquad( double u, double &v1, double &v2, const double a1, const double a2, const double b0, const double b1, const double b2 )
Peasofcake 3:04f3cca82b22 27 {
Peasofcake 3:04f3cca82b22 28 double v = u-a1*v1-a2*v2;
Peasofcake 3:04f3cca82b22 29 double y = b0*v + b1*v1 + b2*v2;
Peasofcake 2:e30dbfec6d1e 30 v2 = v1; v1 = v;
Peasofcake 2:e30dbfec6d1e 31 return y;
Peasofcake 2:e30dbfec6d1e 32 }
Peasofcake 2:e30dbfec6d1e 33
fredwsl 6:c20a8c0f90ed 34 double sliding_average(double u,const int f_N)
fredwsl 6:c20a8c0f90ed 35 {
fredwsl 6:c20a8c0f90ed 36 double f_x[f_N];
fredwsl 6:c20a8c0f90ed 37 double f_sum=0;
fredwsl 8:a1ea1bf49944 38 f_x[1]=abs(u);
fredwsl 6:c20a8c0f90ed 39 for (int i=f_N; i>=1; i--){
fredwsl 6:c20a8c0f90ed 40 f_x[i]=f_x[i-1];
fredwsl 6:c20a8c0f90ed 41 }
fredwsl 6:c20a8c0f90ed 42
fredwsl 6:c20a8c0f90ed 43
fredwsl 6:c20a8c0f90ed 44 for (int i=f_N; i>=0; i--){
fredwsl 6:c20a8c0f90ed 45 f_sum=f_x[i]+f_sum;
fredwsl 6:c20a8c0f90ed 46 }
fredwsl 7:7493a0c5c6aa 47 a=f_sum/double(f_N);
fredwsl 6:c20a8c0f90ed 48 f_sum=0;
fredwsl 6:c20a8c0f90ed 49 return a;
fredwsl 6:c20a8c0f90ed 50 }
fredwsl 6:c20a8c0f90ed 51
Peasofcake 2:e30dbfec6d1e 52
Peasofcake 2:e30dbfec6d1e 53
Peasofcake 2:e30dbfec6d1e 54
Peasofcake 2:e30dbfec6d1e 55 void scopeSend(){
fredwsl 6:c20a8c0f90ed 56 double u1 = EMG.read() ; //filter 1 input
Peasofcake 3:04f3cca82b22 57 double y1 = biquad( u1, f1_v1, f1_v2, f1_a1, f1_a2, f1_b0, f1_b1, f1_b2 );
fredwsl 8:a1ea1bf49944 58 double y2 = biquad( fabs(y1), f2_v1, f2_v2, f2_a1, f2_a2, f2_b0, f2_b1, f2_b2 );
fredwsl 8:a1ea1bf49944 59 //double z1 = 3*sliding_average(y2, N);
fredwsl 8:a1ea1bf49944 60 scope.set(0,y2);
Peasofcake 2:e30dbfec6d1e 61 scope.send();
Peasofcake 2:e30dbfec6d1e 62 }
Peasofcake 3:04f3cca82b22 63
Peasofcake 0:c8a6e00fbdc3 64 int main()
Peasofcake 3:04f3cca82b22 65 {
fredwsl 6:c20a8c0f90ed 66 scopeTimer.attach(&scopeSend,0.002);
Peasofcake 2:e30dbfec6d1e 67 while(1){}
Peasofcake 1:f6110f80fa45 68
Peasofcake 0:c8a6e00fbdc3 69 }