File content as of revision 59:1725a3f02f37:

//=======================================================================================================================================================   
//libraries
#include "mbed.h"           //mbed revision 113
#include "HIDScope.h"       //Hidscope by Tom Lankhorst
#include "BiQuad.h"         //BiQuad by Tom Lankhorst
#include "MODSERIAL.h"      //Modserial
#include "QEI.h"            //QEI library for the encoders


//=======================================================================================================================================================   
//Define objects

//EMG
AnalogIn    emg_biceps_right_in (A0);   //analog in to get EMG biceps  (r) in to c++
AnalogIn    emg_triceps_right_in(A1);   //analog in to get EMG triceps (r) in to c++
AnalogIn    emg_biceps_left_in  (A2);   //analog in to get EMG biceps  (l) in to c++

//Tickers
Ticker      sample_timer;               //ticker for EMG signal sampling, analog becomes digital
Ticker      ticker_switch;              //ticker for switch, every second it is possible to switch
Ticker      ticker_referenceangle;      //ticker for the reference angle
Ticker      ticker_controllerm1;        //ticker for the controller (PID) of motor 1
Ticker      ticker_encoder;             //ticker for encoderfunction motor 1
Ticker      ticker_calibration_biceps;  //ticker for calibration biceps
Ticker      ticker_calibration_triceps; //ticker for calibation triceps

//Timer
Timer       timer;

//Monitoring
HIDScope    scope(5);                   //open 5 channels in hidscope
MODSERIAL pc(USBTX, USBRX);             //pc connection
DigitalOut red(LED_RED);                //LED on K64F board, 1 is out; 0 is on
DigitalOut green(LED_GREEN);            //LED on K64f board, 1 is out; o is on
DigitalOut blue(LED_BLUE);              //LED on K64f board, 1 is out; o is on

//buttons
DigitalIn   button_calibration_biceps  (SW3);    //button to start calibration biceps
DigitalIn   button_calibration_triceps (SW2);    // button to start calibration triceps

//motors
DigitalOut richting_motor1(D7);  //motor 1 connected to motor 1 at k64f board; for turningtable
PwmOut pwm_motor1(D6);
DigitalOut richting_motor2(D4);  //motor 2 connected to motor 2 at k64f board; for linear actuator
PwmOut pwm_motor2(D5);

//encoders
DigitalIn encoder1A(D13);
DigitalIn encoder1B(D12);

//controller
BiQuad PID_controller;                  

//=======================================================================================================================================================   
//define variables

//thresholds
double treshold_biceps_right = 0.04;        //common values that work.
double treshold_biceps_left = -0.04;        //tested on multiple persons 
double treshold_triceps = -0.04;            //triceps and left biceps is specified negative, thus negative treshold


//calibration variables
const float percentage_max_triceps=0.25;    //percentage from max to calculate new treshold
const float percentage_max_biceps =0.3;     //percentage from max to calculate new treshold
double max_biceps;                          //calibration maximum biceps
double max_triceps;                         //calibration maximum triceps

//on/off and switch signals
int switch_signal = 0;        //start of counter, switch made by even and odd numbers
int onoffsignal_biceps;       //on/off signal created by the bicepssignal. (-1: left biceps contract, 0: nothing contracted, 1: right biceps contracted)
int switch_signal_triceps;

//motorvariables
float speedmotor1=0.18; //speed of motor 1 is 0.18 pwm at start
float speedmotor2=1.0;  //speed of motor 2 is 1.0 pwm at start

int cw=0;               //clockwise direction
int ccw=1;              //counterclockwise direction

//encoder
int   counts_encoder1;              //variable to count the pulses given by the encoder, 1 indicates motor 1
float rev_counts_motor1;            //calculated revolutions
float rev_counts_motor1_rad;        //calculated revolutions in rad!
const float gearboxratio=131.25;    //gearboxratio from encoder to motor
const float rev_rond=64.0;          //number of revolutions per rotation 

QEI Encoder1(D13,D12,NC,rev_rond,QEI::X4_ENCODING); //To set the encoder 

//reference
volatile float   d_ref = 0;     //reference angle, starts off 0
const float      w_ref = 1.5;   //reference speed, constant
volatile double  t_start;       //starttime of the timer
volatile double  w_var;         //variable reference speed for making the reference signal 
const double     Ts = 0.001;    //time step for diverse tickers. It is comparable to a frequency of 1000Hz

//controller
const double        Kp = 1.2614;    //calculated value for the proportional action of the PID      
const double        Ki = 0.4219;    //calculated value for the integral action of the PID
const double        Kd = 0.8312;    //calculated value for the derivative action of the PID
const double        N = 100;        //specified value for the filter coefficient of the PID
volatile double     error1;         //calculated error
volatile double     controlOutput;  //output of the PID-controller
bool                start_motor = true; //bool to start the reference when the motor turns


//=======================================================================================================================================================   
//filter coefficients

//b1 = biceps right arm
BiQuad filterhigh_b1(9.5654e-01,-1.9131e+00,9.5654e-01,-1.9112e+00,9.1498e-01);        // second order highpass filter, with frequency of 10 Hz
BiQuad filternotch1_b1 (9.5654e-01, -1.9131e+00, 9.5654e-01 ,-1.9112e+00 ,9.1498e-01;  // IIRnotch filter, with frequency of 50 Hz

//t1= triceps right arm
BiQuad filterhigh_t1(9.5654e-01,-1.9131e+00,9.5654e-01,-1.9112e+00,9.1498e-01);        // second order highpass filter, with frequency of 10 Hz
BiQuad filternotch1_t1 (9.5654e-01, -1.9131e+00, 9.5654e-01 ,-1.9112e+00 ,9.1498e-01;  // IIRnotch filter, with frequency of 50 Hz

//b2= biceps left arm
BiQuad filterhigh_b2(9.5654e-01,-1.9131e+00,9.5654e-01,-1.9112e+00,9.1498e-01);        // second order highpass filter, with frequency of 10 Hz
BiQuad filternotch1_b2 (9.5654e-01, -1.9131e+00, 9.5654e-01 ,-1.9112e+00 ,9.1498e-01;  // IIRnotch filter, with frequency of 50 Hz

//after abs filtering
BiQuad filterlow_b1 (6.2942e-06, 1.2588e-05,6.2942e-06,-1.9929e+00,9.9292e-01);        // second order lowpass filter, with frequency of 2 Hz
BiQuad filterlow_t1 (6.2942e-06, 1.2588e-05,6.2942e-06,-1.9929e+00,9.9292e-01);        // second order lowpass filter, with frequency of 2 Hz
BiQuad filterlow_b2 (6.2942e-06, 1.2588e-05,6.2942e-06,-1.9929e+00,9.9292e-01);        // second order lowpass filter, with frequency of 2 Hz

//=======================================================================================================================================================   
//voids
//=======================================================================================================================================================   

//function teller
void switch_function() {         // The switch function. Makes it possible to switch between the motors. It simply adds one at switch_signal.
    if(switch_signal_triceps==1){
        switch_signal++;
           
    // To monitor what is happening: we will show the text in putty and change led color from red to green or vice versa.
    
        green=!green;
        red=!red;
        
        if (switch_signal%2==0){
             pc.printf("If you contract the biceps, the robot will go right \r\n");    
             pc.printf("If you contract the triceps, the robot will go left \r\n");
             pc.printf("\r\n");
        }
       
    
        else{
             pc.printf("If you contract the biceps, the robot will go up \r\n");
             pc.printf("If you contract the triceps, the robot will go down \r\n");
             pc.printf("\r\n");
        }
     
    }    
}
 
//=======================================================================================================================================================   
//functions which are called in ticker to sample the analog signal and make the on/off and switch signal. 

//Filter void :// funciton which is called in ticker to sample the analog signal and make the on/off and switch signal.
void filter(){
        //biceps right arm read+filtering
       double emg_biceps_right=emg_biceps_right_in.read();                                                      //read the emg value from the elektrodes 
       double emg_filtered_high_biceps_right= filterhigh_b1.step(emg_biceps_right);                             //high pass filter, to remove offset
       double emg_filtered_high_notch_1_biceps_right=filternotch1_b1.step(emg_filtered_high_biceps_right);      //notch filter, to remove noise
       double emg_abs_biceps_right=fabs(emg_filtered_high_notch_1_biceps_right);                                //rectify the signal, fabs because float   
       double emg_filtered_biceps_right=filterlow_b1.step(emg_abs_biceps_right);                                //low pass filter to envelope the signal
        
        //triceps right arm read+filtering
       double emg_triceps_right=emg_triceps_right_in.read();                                                    //read the emg value from the elektrodes
       double emg_filtered_high_triceps_right= filterhigh_t1.step(emg_triceps_right);                           //high pass filter, to remove offset
       double emg_filtered_high_notch_1_triceps_right=filternotch1_t1.step(emg_filtered_high_triceps_right);    //notch filter, to remove noise
       double emg_abs_triceps_right=fabs(emg_filtered_high_notch_1_triceps_right);                              //rectify the signal, fabs because float   
       double emg_filtered_triceps_right=filterlow_t1.step(emg_abs_triceps_right);                              //low pass filter to envelope the signal
        
        //biceps left arm read+filtering
       double emg_biceps_left=emg_biceps_left_in.read();                                                    //read the emg value from the elektrodes
       double emg_filtered_high_biceps_left= filterhigh_b2.step(emg_biceps_left);                           //high pass filter, to remove offset
       double emg_filtered_high_notch_1_biceps_left=filternotch1_b2.step(emg_filtered_high_biceps_left);    //notch filter, to remove noise
       double emg_abs_biceps_left=fabs(emg_filtered_high_notch_1_biceps_left);                              //rectify the signal, fabs because float   
       double emg_filtered_biceps_left=filterlow_b2.step(emg_abs_biceps_left);                              //low pass filter to envelope the signal
               
        //creating of on/off signal with the created on/off signals, with if statement   for right arm!    
       //signal substraction of filter biceps and triceps. right Biceps + left biceps -
       double signal_biceps_sum=emg_filtered_biceps_right-emg_filtered_biceps_left;
       double bicepstriceps_rightarm=emg_filtered_biceps_right-emg_filtered_triceps_right;       
        
        //creating of on/off signal with the created on/off signals, with if statement   for right arm!    
        if (signal_biceps_sum>treshold_biceps_right){
            onoffsignal_biceps=1;
        }
          
        else if (signal_biceps_sum<treshold_biceps_left){
            onoffsignal_biceps=-1;
        }    
        
        else{
            onoffsignal_biceps=0;
        }
                      
        //creating on/off signal for switch (left arm)
        
        if (bicepstriceps_rightarm<treshold_triceps){
            switch_signal_triceps=1;            
        }    
        
        else{        
            switch_signal_triceps=0;       
        }
        
        //send signals  to scope to monitor the EMG signals
        scope.set(0, emg_filtered_biceps_right);            //set emg signal of right biceps to scope in channel 0
        scope.set(1, emg_filtered_triceps_right);           // set emg signal of right triceps to scope in channel 1
        scope.set(2, emg_filtered_biceps_left);             // set emg signal of left biceps to scope in channel 2
        scope.set(3, bicepstriceps_rightarm);               // set on/off signal for the motors to scope in channel 3
        scope.set(4, switch_signal_triceps);                // set the switch signal to scope in channel 4 
        
        scope.send();         //send all the signals to the scope
}
//=======================================================================================================================================================   

//reference void makes the reference that the controllor should follow. There is only a controller for motor 1. 
void reference(){                       
    if (start_motor == true){         //bool that is true when the motor starts turning
        timer.start();                //timer that starts counting in milliseconds
    }
    if (onoffsignal_biceps==-1 && switch_signal%2==0){  //the signal of the biceps is -1 and the switch is even, so motor 1 is being controlled      
         t_start = timer.read_ms();     //read the current time passed from the timer
         start_motor = false;           //it means that the motor is not running or has started up
         
        if (t_start < 1.0){            //the time passed is less than one second
            w_var = t_start*1.5;       //the reference velocity is the time passed multiplied with the eventual constant velocity it should reach
        }
            
        else{
            w_var = 1.5;                //if the time passed is more than one second, the velocity is constant
        }
         
         d_ref = d_ref + w_var * Ts;    //makes the reference angle
         
    }
         if (d_ref > 12){               //set the restrictions
            d_ref = 12;
            start_motor = true;         //after the restriction is reached the motor (if turned the other way) will start up again so the bool has to be set to true
         }
         
    else{ 
        d_ref = d_ref;                  //if there is no signal, the referance angle is constant
    }
    
    if (onoffsignal_biceps==1 && switch_signal%2==0){   //the signal of the biceps is -1 and the switch is even, so motor 1 is being controlled
        t_start = timer.read_ms();
        start_motor = false;
        
        if (t_start < 1.0){
            w_var = t_start*1.5;
        }
        
        else {
            w_var = 1.5;
        }
        d_ref = d_ref - w_var * Ts;             //the motor should turn the other way now so the reference becomes negative     
    }
    
        if (d_ref < -12){       //negative restriction
            d_ref = -12;
            start_motor = true;
        }
        
    else{
        d_ref = d_ref;
    }
    
}
//=======================================================================================================================================================   
//This void calculates the error and makes the control output. 
void m1_controller(){
    error1 = d_ref-rev_counts_motor1_rad;               //calculate the error = reference-output
    controlOutput = PID_controller.step(error1);        //give the error as input to the controller
}
//=======================================================================================================================================================   

//This void calculated the number of rotations that the motor has done in rad. It is put in a void because with the ticker, this ensures that it is updated continuously. 
void encoders(){
    counts_encoder1 = Encoder1.getPulses();
    rev_counts_motor1 = (float)counts_encoder1/(gearboxratio*rev_rond);
    rev_counts_motor1_rad = rev_counts_motor1*6.28318530718;    //calculate the angle in radians
}

//=======================================================================================================================================================   

//The calibration of the Biceps threshold is started by a button. 
//It determines the maximum reachable EMG signal and takes a percentage of this to determine the new threshold. 
void calibration_biceps(){
        if (button_calibration_biceps==0){              //only runs when button is pressed
            
            //detach tickers of other voids that control the switched and motors. To avoid unwanted moving and switching of the motors. 
            ticker_switch.detach();
            sample_timer.detach();
            
            //let the user know what is happening, blue led on: calibration is going. 
            pc.printf("start of calibration biceps, contract maximal \r\n");
            pc.printf("\r\n");
            red=1;
            green=1;
            blue=0;
 
 //start callibration of biceps      
            for(int n =0; n<1500;n++){                                                  //read for 1500 samples as calibration
                
               //biceps right arm read+filtering
               double emg_biceps_right=emg_biceps_right_in.read();                                                      //read the emg value from the elektrodes 
               double emg_filtered_high_biceps_right= filterhigh_b1.step(emg_biceps_right);                             //high pass filter, to remove offset
               double emg_filtered_high_notch_1_biceps_right=filternotch1_b1.step(emg_filtered_high_biceps_right);      //notch filter, to remove noise
               double emg_abs_biceps_right=fabs(emg_filtered_high_notch_1_biceps_right);                                //rectify the signal, fabs because float   
               double emg_filtered_biceps_right=filterlow_b1.step(emg_abs_biceps_right);                                //low pass filter to envelope the signal
               
                //triceps right arm read+filtering
               double emg_triceps_right=emg_triceps_right_in.read();                                                    //read the emg value from the elektrodes
               double emg_filtered_high_triceps_right= filterhigh_t1.step(emg_triceps_right);                           //high pass filter, to remove offset
               double emg_filtered_high_notch_1_triceps_right=filternotch1_t1.step(emg_filtered_high_triceps_right);    //notch filter, to remove noise
               double emg_abs_triceps_right=fabs(emg_filtered_high_notch_1_triceps_right);                              //rectify the signal, fabs because float   
               double emg_filtered_triceps_right=filterlow_t1.step(emg_abs_triceps_right);                              //low pass filter to envelope the signal
               
               //biceps is +, triceps is -
               double bicepstriceps_rightarm=emg_filtered_biceps_right-emg_filtered_triceps_right; 
                                
                    if (bicepstriceps_rightarm > max_biceps){                    //determine what the highest reachable emg signal is
                
                        max_biceps = bicepstriceps_rightarm;
            
                    }
                wait(0.001f); //to sample at same freq; 1000Hz
            }
            
            treshold_biceps_right=percentage_max_biceps*max_biceps; //determine new treshold, right biceps is +
            treshold_biceps_left=-treshold_biceps_right;            //determine new treshold, right biceps is -
            
            //toggle lights to see the calibration is done. Also show in putty that the calibration is done. 
            blue=!blue;
            
            pc.printf(" end of calibration\r\n",treshold_biceps_right );   
            pc.printf(" change of cv biceps: %f ",treshold_biceps_right );
            
            wait(0.2f);
            
            //remind the person of what motor will go on an which direction  
                if (switch_signal%2==0){
                    green=0;
                    red=1;
                }
            
                else{
                    green=1;
                    red=0;
                }
        }
    //reattach the functions to the tickers that were detached.     
    ticker_switch.attach(&switch_function,1.0);
    sample_timer.attach(&filter, 0.001);
}
//=======================================================================================================================================================   

//The calibration of the triceps threshold is started by a button. 
//It determines the maximum reachable EMG signal and takes a percentage of this to determine the new threshold. 
void calibration_triceps(){
        if(button_calibration_triceps==0){      //only runs when button is pressed
        
            //detach tickers of other voids that control the switched and motors. To avoid unwanted moving and switching of the motors. 
            ticker_switch.detach();
            sample_timer.detach();
            
            //toggel LEDS and let the user know that callibration of triceps is starting. 
            red=1;
            green=1;
            blue=0;
          
            pc.printf("start of calibration triceps\r\n");
            pc.printf("\r\n");

        //start calibration of triceps 
                for(int n =0; n<1500;n++){                                                  //read for 2000 samples as calibration
    
                     //biceps right arm read+filtering
                   double emg_biceps_right=emg_biceps_right_in.read();                                                      //read the emg value from the elektrodes 
                   double emg_filtered_high_biceps_right= filterhigh_b1.step(emg_biceps_right);                             //high pass filter, to remove offset
                   double emg_filtered_high_notch_1_biceps_right=filternotch1_b1.step(emg_filtered_high_biceps_right);      //notch filter, to remove noise
                   double emg_abs_biceps_right=fabs(emg_filtered_high_notch_1_biceps_right);                                //rectify the signal, fabs because float   
                   double emg_filtered_biceps_right=filterlow_b1.step(emg_abs_biceps_right);                                //low pass filter to envelope the signal
                   
                    //triceps right arm read+filtering
                   double emg_triceps_right=emg_triceps_right_in.read();                                                    //read the emg value from the elektrodes
                   double emg_filtered_high_triceps_right= filterhigh_t1.step(emg_triceps_right);                           //high pass filter, to remove offset
                   double emg_filtered_high_notch_1_triceps_right=filternotch1_t1.step(emg_filtered_high_triceps_right);    //notch filter, to remove noise
                   double emg_abs_triceps_right=fabs(emg_filtered_high_notch_1_triceps_right);                              //rectify the signal, fabs because float   
                   double emg_filtered_triceps_right=filterlow_t1.step(emg_abs_triceps_right);                              //low pass filter to envelope the signal
                   
                   //biceps is +, triceps is -
                   double bicepstriceps_rightarm=emg_filtered_biceps_right-emg_filtered_triceps_right; 
                                        
                        if (bicepstriceps_rightarm < max_triceps){                    //determine what the lowest reachable emg of triceps (max in negative part) signal is
                            
                        max_triceps = bicepstriceps_rightarm;
                        
                        }
                    wait(0.001f); //to sample at same freq; 1000Hz
                }
            treshold_triceps=percentage_max_triceps*max_triceps;        //calculate the new treshold. This is a negative number due to the sum!
                        
            //Let the user know that the calibration is done. 
            pc.printf(" end of calibration\r\n");   
            pc.printf(" change of cv triceps: %f ",treshold_triceps ); 
            blue=!blue;
            wait(0.2f);
                if (switch_signal%2==0){
                    green=0;
                    red=1;
                }
                        
                else{
                    green=1;
                    red=0;
                }  
            }
                
    //reattach the functions to the tickers that were detached. 
    sample_timer.attach(&filter, 0.001);    
    ticker_switch.attach(&switch_function,1.0);    
}
//=======================================================================================================================================================   

//=======================================================================================================================================================   
//program
//=======================================================================================================================================================   
int main(){  

    pc.baud(115200); //connect with pc with baudrate 115200
    green=1;            //led is off (1), at beginning  
    blue=1;             //led is off (1), at beginning
    red=0;              //led is on (0),  at beginning
    
    //attach tickers to functions
    sample_timer.attach(&filter, Ts);                             //continously execute the EMG reader and filter, it ensures that filter and sampling is executed every 1/frequency seconds
    ticker_switch.attach(&switch_function,1.0);                   //it is possible to switch only once in a second, this ensures that the switch is not reacting on one signal multiple times.
    ticker_referenceangle.attach(&reference, Ts);
    ticker_controllerm1.attach(&m1_controller, Ts);
    ticker_encoder.attach(&encoders, Ts);
    ticker_calibration_biceps.attach (&calibration_biceps,2.0);   //to call calibration biceps, stop EMG sampling and switch
    ticker_calibration_triceps.attach(&calibration_triceps,2.0);  //to call calibration triceps, stop EMG sampling and switch
    
    //PID controller
    PID_controller.PIDF(Kp,Ki,Kd,N,Ts);
    
    //Encoder
    //QEI Encoder1(D13,D12, NC, rev_rond,QEI::X4_ENCODING);
    
    //Show the user what the starting motor will be and what will happen
    pc.printf("We will start the demonstration\r\n");
    pc.printf("\r\n\r\n\r\n");

        if (switch_signal%2==0){  
            pc.printf("If you contract the biceps, the robot will go right \r\n");
            pc.printf("If you contract the triceps, the robot will go left \r\n");
            pc.printf("\r\n");
         }
       
    
        else{
            pc.printf("If you contract the biceps, the robot will go up \r\n");
            pc.printf("If you contract the triceps, the robot will go down \r\n");
            pc.printf("\r\n");
        }
     
//=======================================================================================================================================================   
//endless loop


    while (true) {                      //neverending loop
        
        if (onoffsignal_biceps==-1){    //left biceps contracted                        
    
            if (switch_signal%2==0){    //switch even                    
          
                speedmotor1=controlOutput;  //output PID-controller is the speed for motor1

                if (speedmotor1<0){         //if the output of the controller is negative, the direction is clockwise
                    richting_motor1 = cw;      //motor 1, right
                }
                else   {                    //if the output is positive, the direction is counterclockwise
                    richting_motor1 = ccw;     //motor 1, left
                }
                pwm_motor1 = fabs(speedmotor1);  //speed of motor 1, absolute because pwm cannot be negative
               
            } 
            
         
            else{               //switch odd        
         
                richting_motor2 = ccw;    //motor 2, up 
                pwm_motor2 = speedmotor2; //speed of motor 2
           
            }      
              
        }
        else if (onoffsignal_biceps==1){       //right biceps contracted
        
            if (switch_signal%2==0){           //switch signal even         
                speedmotor1=controlOutput;
     
                if (speedmotor1<0){         //the same as for the left biceps, the robot turns in the right direction because of the reference signal
                    richting_motor1 = cw;   //motor 1, right
                }
                else {
                    richting_motor1 = ccw;  //motor 1, left
                }
                pwm_motor1 = fabs(speedmotor1);      //speed of motor 1
          
            } 
            else{                           //switch signal odd
                richting_motor2 = cw;       //motor 2, down
                pwm_motor2 = speedmotor2;   //speed motor 2
                
            }  
        }   
        else{ 
            //no contraction of biceps, thus no motoraction.   
            pwm_motor2=0;
            pwm_motor1=0;
            start_motor = true;             //every time the motor is off, the bool is reset so that the reference void can start when the motor starts
    
        }              
               
    } //while true closed
        
} //int main closed

//=======================================================================================================================================================