4 directional EMG control of the XY table. Made during my bachelor end assignment.

Dependencies:   C12832_lcd HIDScope mbed-dsp mbed

main.cpp

Committer:
jessekaiser
Date:
2015-06-05
Revision:
48:05adf4978828
Parent:
47:150924ff4b2c
Child:
49:056c4de3591e

File content as of revision 48:05adf4978828:

/*Code by Jesse Kaiser, s1355783 for control of the 2DOF Planar Table
Some variables are also numbered at the end. The numbers stands for the muscle that controls it.
Biceps =            1
Triceps =           2
Pectoralis Major =  3
Deltoid =           4
The "x" and "y" at the end of variables stand for the X-Spindle or Y-Spindle respectivly. 
*/

#include "mbed.h"
#include "C12832_lcd.h"
#include "arm_math.h"
#include "HIDScope.h"

#define K_Gain      14      //Gain of the filtered EMG signal
#define Damp        5       //Deceleration of the motor
#define Mass        1       // Mass value
#define dt          0.002   //Sample frequency
#define MAX_bi      0.09    //Can be used for normalisation of the EMG signal of the biceps
#define MAX_tri     0.09
#define MAX_pect    0.09
#define MAX_delt    0.09
#define MIN_freq    500     //The motor turns off below this frequency
#define EMG_tresh   0.02

//Motor control
DigitalOut Dirx(p12);
DigitalOut Diry(p13);
PwmOut Stepx(p21);
PwmOut Stepy(p22);

//Signal to and from computer
Serial pc(USBTX, USBRX);

DigitalOut Enablex(p24); //Connected to green led
DigitalOut Enabley(p25); //Connected to blue led 

//Microstepping
DigitalOut MS1(p27);
DigitalOut MS2(p28);
DigitalOut MS3(p29);

//Potmeter and EMG
AnalogIn Pot1(p19);
AnalogIn Pot2(p20);

AnalogIn emg1(p15); //EMG bordje bovenop, biceps
AnalogIn emg2(p16); //triceps
AnalogIn emg3(p17);
AnalogIn emg4(p18);

HIDScope scope(4);
Ticker   scopeTimer;

//lcd
C12832_LCD lcd;

//Variables for motor control
float setpoint = 1000; //Frequentie setpint
float step_freq1 = 1;
float step_freq2 = 1;
float step_freq3 = 1;
float step_freq4 = 1; 

//EMG filter
arm_biquad_casd_df1_inst_f32 lowpass_biceps;
arm_biquad_casd_df1_inst_f32 lowpass_triceps;
arm_biquad_casd_df1_inst_f32 lowpass_pect;
arm_biquad_casd_df1_inst_f32 lowpass_deltoid;
//lowpass filter settings: Fc = 2 Hz, Fs = 500 Hz, Gain = -3 dB
float lowpass_const[] = {0.00015514839749793376, 0.00031029679499586753, 0.00015514839749793376, 1.9644602512795832, -0.9650808448695751};
arm_biquad_casd_df1_inst_f32 highnotch_biceps;
arm_biquad_casd_df1_inst_f32 highnotch_triceps;
arm_biquad_casd_df1_inst_f32 highnotch_pect;
arm_biquad_casd_df1_inst_f32 highnotch_deltoid;
//highpass filter settings: Fc = 20 Hz, Fs = 500 Hz, notch Fc = 50, Fs = 500 Hz
float highnotch_const[] = {0.8370879899975344, -1.6741759799950688, 0.8370879899975344, 1.6474576182593796, -0.7008943417307579, 0.7063988100714527, -1.1429772843080923, 0.7063988100714527, 1.1429772843080923, -0.41279762014290533};

//state values
float lowpass_biceps_states[4];
float highnotch_biceps_states[8];
float lowpass_triceps_states[4];
float highnotch_triceps_states[8];
float lowpass_pect_states[4];
float highnotch_pect_states[8];
float lowpass_deltoid_states[4];
float highnotch_deltoid_states[8];

//global variabels
float filtered_biceps, filtered_triceps, filtered_pect, filtered_deltoid;
float speed_old1, speed_old2, speed_old3, speed_old4;
float acc1, acc2, acc3, acc4;
float force1, force2, force3, force4;
float speed1, speed2, speed3, speed4;
float damping1, damping2, damping3, damping4;

void looper_emg()
{
    float emg_value1_f32, emg_value2_f32, emg_value3_f32, emg_value4_f32;
    emg_value1_f32 = emg1.read();
    emg_value2_f32 = emg2.read();
    emg_value3_f32 = emg3.read();
    emg_value4_f32 = emg4.read();

    //process emg biceps
    arm_biquad_cascade_df1_f32(&highnotch_biceps, &emg_value1_f32, &filtered_biceps, 1 );   //High pass and notch filter
    filtered_biceps = fabs(filtered_biceps);                                                //Rectifier
    arm_biquad_cascade_df1_f32(&lowpass_biceps, &filtered_biceps, &filtered_biceps, 1 );    //low pass filter

    //process emg triceps
    arm_biquad_cascade_df1_f32(&highnotch_triceps, &emg_value2_f32, &filtered_triceps, 1 );
    filtered_triceps = fabs(filtered_triceps);
    arm_biquad_cascade_df1_f32(&lowpass_triceps, &filtered_triceps, &filtered_triceps, 1 );

    //process emg pectoralis major
    arm_biquad_cascade_df1_f32(&highnotch_pect, &emg_value3_f32, &filtered_pect, 1 );
    filtered_pect = fabs(filtered_pect);
    arm_biquad_cascade_df1_f32(&lowpass_pect, &filtered_pect, &filtered_pect, 1 );

    //process emg deltoid
    arm_biquad_cascade_df1_f32(&highnotch_deltoid, &emg_value4_f32, &filtered_deltoid, 1 );
    filtered_deltoid = fabs(filtered_deltoid);
    arm_biquad_cascade_df1_f32(&lowpass_deltoid, &filtered_deltoid, &filtered_deltoid, 1 );

    /*send value to PC. */
    scope.set(0,filtered_biceps); //Filtered EMG signal
    scope.set(1,filtered_triceps);
    scope.set(2,filtered_pect);
    scope.set(3,filtered_deltoid); 
}

void looper_motory()
{
    //Vooruit
    force1 = K_Gain*(filtered_biceps/MAX_bi);
    force1 = force1 - damping1;
    acc1 = force1/Mass;
    speed1 = speed_old1 + (acc1 * dt);
    damping1 = speed1 * Damp;
    step_freq1 = (setpoint*speed1);
    speed_old1 = speed1;
    
    //Achteruit triceps
    force2 = K_Gain*(filtered_triceps/MAX_tri);
    force2 = force2 - damping2;
    acc2 = force2/Mass;
    speed2 = speed_old2 + (acc2 * dt);
    damping2 = speed2 * Damp;
    step_freq2 = (setpoint*speed2);
    speed_old2 = speed2;
    if (filtered_biceps > filtered_triceps) {
        Diry = 0;
        speed2 = 0.01;
        speed_old2 = 0.01;
        Stepy.period(1.0/step_freq1);
    } if (filtered_triceps > filtered_biceps) {
        Diry = 1;
        speed1 = 0.01;
        speed_old1 = 0.01;  
        Stepy.period(1.0/step_freq2);
    }
    //Speed limit
    if (speed1 > 1) {
        speed1 = 1;
        step_freq1 = setpoint;
    }
    if (speed2 > 1) {
        speed2 = 1;
        step_freq2 = setpoint;
    }
    //EMG treshold
    if (filtered_biceps < EMG_tresh && filtered_triceps < EMG_tresh) {
        Enabley = 1; //Enable = 1 turns the motor off. 
        speed1 = 0.01;
        speed_old1 = 0.01;
        speed2 = 0.01;
        speed_old2 = 0.01;
    } else {
        Enabley = 0;
    }

}

void looper_motorx()
{
    //To the left
    force3 = K_Gain*(filtered_pect/MAX_pect);
    force3 = force3 - damping3;
    acc3 = force3/Mass;
    speed3 = speed_old3 + (acc3 * dt);
    damping3 = speed3 * Damp;
    step_freq3 = (setpoint*speed3);
    speed_old3 = speed3;
    
    //To the right
    force4 = K_Gain*(filtered_deltoid/MAX_delt);
    force4 = force4 - damping4;
    acc4 = force4/Mass;
    speed4 = speed_old4 + (acc4 * dt);
    damping4 = speed4 * Damp;
    step_freq4 = (setpoint*speed4);
    speed_old4 = speed4;
    if (filtered_pect > filtered_deltoid) {
        Dirx = 0;
        speed4 = 0.01;
        speed_old4 = 0.01;
        Stepx.period(1.0/step_freq3);
    } if (filtered_deltoid > filtered_pect) {
        Dirx = 1;
        speed3 = 0.01;
        speed_old3 = 0.01;  
        Stepx.period(1.0/step_freq4);
    }
    //Speed limit
    if (speed3 > 1) {
        speed3 = 1;
        step_freq3 = setpoint;
    }
    if (speed4 > 1) {
        speed4 = 1;
        step_freq4 = setpoint;
    }
    //EMG treshold
    if (filtered_pect < EMG_tresh && filtered_deltoid < EMG_tresh) {
        Enablex = 1; //Enable = 1 turns the motor off. 
        speed3 = 0.01;
        speed_old3 = 0.01;
        speed4 = 0.01;
        speed_old4 = 0.01;
    } else {
        Enablex = 0;
    }

}
int main()
{
    // Attach the HIDScope::send method from the scope object to the timer at 500Hz. Hier wordt de sample freq aangegeven.
    scopeTimer.attach_us(&scope, &HIDScope::send, 2e3);

    Ticker emgtimer;    //biceps
    arm_biquad_cascade_df1_init_f32(&lowpass_biceps, 1 , lowpass_const, lowpass_biceps_states);
    arm_biquad_cascade_df1_init_f32(&highnotch_biceps, 2 , highnotch_const, highnotch_biceps_states);
    //triceps
    arm_biquad_cascade_df1_init_f32(&lowpass_triceps, 1 , lowpass_const, lowpass_triceps_states);
    arm_biquad_cascade_df1_init_f32(&highnotch_triceps, 2 , highnotch_const, highnotch_triceps_states);
    //pectoralis major   
    arm_biquad_cascade_df1_init_f32(&lowpass_pect, 1 , lowpass_const, lowpass_pect_states);
    arm_biquad_cascade_df1_init_f32(&highnotch_pect, 2 , highnotch_const, highnotch_pect_states);
    //deltoid
    arm_biquad_cascade_df1_init_f32(&lowpass_deltoid, 1 , lowpass_const, lowpass_deltoid_states);
    arm_biquad_cascade_df1_init_f32(&highnotch_deltoid, 2 , highnotch_const, highnotch_deltoid_states);
    emgtimer.attach(looper_emg, 0.002);

    Ticker looptimer;
    looptimer.attach(looper_motorx, 0.01); //X-Spindle motor, why this freq?
    //looptimer.attach(looper_motory, 0.01); //Y-Spindle motor
    
    //Microstepping control, now configured as half stepping (MS1=1,MS2=0,MS3=0)
    MS1 = 1;
    MS2 = 0;
    MS3 = 0;
    Stepx.write(0.5); // Duty cycle of 50%
    Stepy.write(0.5);

    while (1) {

        //lcd.printf("Bi %.2f ,Tri %.2f \n", filtered_biceps, filtered_triceps); Filtered EMG values 
        lcd.printf("1 %.0f, 2 %.0f, 3 %.0f, 4 %.0f \n", step_freq1, step_freq2, step_freq3, step_freq4); //step_freq value of every EMG sensor
        wait(0.01);
    }
}