a biquad working
Dependencies: HIDScope mbed QEI
main.cpp
- Committer:
- yohoo15
- Date:
- 2015-10-27
- Revision:
- 3:2f75bb307da3
- Parent:
- 2:241b572207fb
- Child:
- 4:61d5e7417c4c
File content as of revision 3:2f75bb307da3:
#include "mbed.h" //#include "read_filter_emg.h" //included for fabs() function #include <math.h> #include "HIDScope.h" #include <iostream> #include "QEI.h" // Define pin for motor control DigitalOut directionPin(D4); PwmOut PWM(D5); DigitalIn buttonccw(PTA4); DigitalIn buttoncw(PTC6); // define ticker Serial pc(USBTX, USBRX); Ticker HIDScope_timer; Ticker Filteren_timer; Ticker aansturen; HIDScope scope(2); // defining flags volatile bool Flag_filteren = false; volatile bool Flag_HIDScope = false; volatile bool left_movement = false; // making function flags. void Go_flag_filteren() { Flag_filteren = true; } void Go_flag_HIDScope() { Flag_HIDScope = true; } AnalogIn analog_emg_left(A0); //AnalogIn analog_emg_right(A1); double input = 0; double filter_signal_hid = 0; //double input_right = 0; //*** making the v for everything and conquer the world*** //for Notchfilter double notch_v11=0; double notch_v21=0; double notch_v12=0; double notch_v22=0; double notch_v13=0; double notch_v23=0; //for highpass filter double high_v11=0; double high_v21=0; double high_v12=0; double high_v22=0; double high_v13=0; double high_v23=0; // for lowpasfilter double low_v11=0; double low_v21=0; double low_v12=0; double low_v22=0; double low_v13=0; double low_v23=0; // for moving average double n1 = 0; double n2 = 0; double n3 = 0; double n4 = 0; double n5 = 0; double filter_left; double filter_right; //general biquad filter that can be called in all the filter functions double biquad(double u, double &v1, double &v2, const double a1, const double a2, const double b0, const double b1, const double b2) { double v = u - a1*v1 - a2*v2; double y = b0*v + b1*v1 + b2*v2; //values of v2 and v1 are updated, as they are passed by reference //they update globally v2 = v1; v1 = v; return y; } double moving_average(double y, double &n1, double &n2, double &n3, double &n4, double &n5) { double average = (y + n1 + n2 +n3 + n4 + n5)/5; n5 = n4; n4 = n3; n3 = n2; n2 = n1; n1 = y; return average; } /* double threshold(double signal, const double lowtreshold, const double hightreshold) { if (signal > hightreshold) left = true; else if (signal <lowtreshold) left = false; } */ //Specifying filter coefficients highpass /* notch filter with 3 cascaded biquads*/ //first notch biquad const double notch1_a1 = -1.55951422433; const double notch1_a2 = 0.92705680308; const double notch1_b0 = 1.00000000000; const double notch1_b1 = -1.61854515325; const double notch1_b2 = 1.00000000000; //second notch biquad const double notch2_a1 = -1.54767435801; const double notch2_a2 = 0.96124842048; const double notch2_b0 = 1.00000000000; const double notch2_b1 = -1.61854515325; const double notch2_b2 = 1.00000000000; //third notch biquad const double notch3_a1 = -1.62600366964; const double notch3_a2 = 0.96453460373; const double notch3_b0 = 1.00000000000; const double notch3_b1 = -1.61854515325; const double notch3_b2 = 1.00000000000; /* high pass filter consists of three cascaded biquads blow coefficients for those three biquads */ //first high pass biquad const double highp1_a1 = -0.67538034389; const double highp1_a2 = 0.12769255668; const double highp1_b0 = 1.00000000000; const double highp1_b1 = -2.00000000000; const double highp1_b2 = 1.00000000000; //second high pass biquad const double highp2_a1 = -0.76475499450; const double highp2_a2 = 0.27692273367; const double highp2_b0 = 1.00000000000; const double highp2_b1 = -2.00000000000; const double highp2_b2 = 1.00000000000; //third high pass biquad const double highp3_a1 = -0.99216561242; const double highp3_a2 = 0.65663360837; const double highp3_b0 = 1.00000000000; const double highp3_b1 = -2.00000000000; const double highp3_b2 = 1.00000000000; /* lowpass filter consists of three cascaded biquads below the coefficients for those three biquads */ //first low pass biquad const double lowp1_a1 = -1.05207469728; const double lowp1_a2 = 0.28586907478; const double lowp1_b0 = 1.00000000000; const double lowp1_b1 = 2.00000000000; const double lowp1_b2 = 1.00000000000; //second low pass biquad const double lowp2_a1 = -1.16338171052; const double lowp2_a2 = 0.42191097989; const double lowp2_b0 = 1.00000000000; const double lowp2_b1 = 2.00000000000; const double lowp2_b2 = 1.00000000000; //third low pass biquad const double lowp3_a1 = -1.42439823874; const double lowp3_a2 = 0.74093118112; const double lowp3_b0 = 1.00000000000; const double lowp3_b1 = 2.00000000000; const double lowp3_b2 = 1.00000000000; double Filteren() { input = analog_emg_left.read(); input = input-0.45; //FIRST SUBTRACT MEAN THEN FILTER //input_right = analog_emg_right.read(); // notch filter double y1 = biquad(input, notch_v11, notch_v21, notch1_a1, notch1_a2, notch1_b0, notch1_b1, notch1_b2); double y2 = biquad(y1, notch_v12, notch_v22, notch2_a1, notch2_a2, notch2_b0, notch2_b1, notch2_b2); double y3 = biquad(y2, notch_v13, notch_v23, notch3_a1, notch3_a2, notch3_b0, notch3_b1, notch3_b2); //higpass filter double y4 = biquad(y3, high_v11, high_v21, highp1_a1, highp1_a2, highp1_b0, highp1_b1, highp1_b2); double y5 = biquad(y4, high_v12, high_v22, highp2_a1, highp2_a2, highp2_b0, highp2_b1, highp2_b2); double y6 = biquad(y5, high_v13, high_v23, highp3_a1, highp3_a2, highp3_b0, highp3_b1, highp3_b2); //rectivier double y7 = fabs(y6); //lowpas filter cascade double y8 = biquad(y7, low_v11, low_v21, lowp1_a1, lowp1_a2, lowp1_b0, lowp1_b1, lowp1_b2); double y9 = biquad(y8, low_v12, low_v22, lowp2_a1, lowp2_a2, lowp2_b0, lowp2_b1, lowp2_b2); double y10= biquad(y9, low_v13, low_v23, lowp3_a1, lowp3_a2, lowp3_b0, lowp3_b1, lowp3_b2); // moving average double filter_signal = moving_average(y10,n1,n2,n3,n4,n5); double high_threshold = 1200; double low_threshold = 500; if (filter_signal > high_threshold) { left_movement = true; } else if (filter_signal < low_threshold) { left_movement = false; } return(filter_signal); } /*************************************************************motor control******************************************************************************************************/ void HIDScope_kijken() { scope.set(0, input); scope.set(1, filter_signal_hid); scope.send(); } int main() { HIDScope_timer.attach(&Go_flag_HIDScope, 0.002); Filteren_timer.attach(&Go_flag_filteren,0.004); while(1) { if(Flag_filteren) { Flag_filteren = false; filter_signal_hid = Filteren(); } if(Flag_HIDScope) { Flag_HIDScope = false; HIDScope_kijken(); } if(left_movement) { pc.printf("left = true /n"); } } }