File content as of revision 15:5d24f832bb7b:

#include "BiQuad.h"
#include "FastPWM.h"
#include "HIDScope.h"
#include <math.h>
#include "mbed.h"
#include "MODSERIAL.h"
#include "QEI.h"
 
const double pi = 3.1415926535897;                                              // Definition of pi

// SERIAL COMMUNICATION WITH PC ////////////////////////////////////////////////
MODSERIAL pc(USBTX, USBRX);
HIDScope scope(4);
 
// STATES //////////////////////////////////////////////////////////////////////
enum states{MOTORS_OFF, CALIBRATING, MOVING, HITTING};
states currentState = MOTORS_OFF;                                               // Start with motors off
bool stateChanged = true;                                                       // Make sure the initialization of first state is executed
 
// ENCODER /////////////////////////////////////////////////////////////////////
QEI Encoder1(D10,D11,NC,32);                                                    // CONNECT ENC1A TO D10, ENC1B TO D11
QEI Encoder2(D12,D13,NC,32);                                                    // CONNECT ENC2A TO D12, ENC2B TO D13
 
// PINS ////////////////////////////////////////////////////////////////////////
DigitalOut motor1DirectionPin(D4);                                              // Value 0: CCW; 1: CW
PwmOut motor1MagnitudePin(D5);
DigitalOut motor2DirectionPin(D7);                                              // Value 0: CW or CCW?; 1: CW or CCW?
PwmOut motor2MagnitudePin(D6);
InterruptIn button1(D2);                                                        // CONNECT BUT1 TO D2
InterruptIn button2(D3);                                                        // CONNECT BUT2 TO D3
InterruptIn button3(SW2);                                                       
InterruptIn button4(SW3);
AnalogIn potmeter1(A0);                                                         // CONNECT POT1 TO A0
AnalogIn potmeter2(A1);                                                         // CONNECT POT2 TO A1
DigitalOut led1(LED_RED);
DigitalOut led2(LED_BLUE);
DigitalOut led3(LED_GREEN);
DigitalOut led4(D8);                                                            // CONNECT LED1 TO D8
DigitalOut led5(D9);                                                            // CONNECT LED2 TO D9
AnalogIn emg_r(A2);                                                             // CONNECT EMG TO A2
AnalogIn emg_l(A3);                                                             // CONNECT EMG TO A3
 
// MOTOR CONTROL ///////////////////////////////////////////////////////////////
Ticker controllerTicker;                                                        // Ticker for the controller
const double controller_Ts = 1/200.1;                                           // Time step for controllerTicker [s]
const double motorRatio = 131.25;                                               // Ratio of the gearbox in the motors []
const double radPerPulse = 2*pi/(32*motorRatio);                                // Amount of radians the motor rotates per encoder pulse [rad/pulse]
volatile double xVelocity = 0, yVelocity = 0;                                   // X and Y velocities of the end effector at the start
double velocity = 0.01;                                                         // X and Y velocity of the end effector when desired
 
// MOTOR 1
volatile double position1;                                                      // Position of motor 1 [rad]
volatile double reference1 = 0;                                                 // Desired rotation of motor 1 [rad]
double motor1Max = 0;                                                           // Maximum rotation of motor 1 [rad]
double motor1Min = 2*pi*-40/360;                                                // Minimum rotation of motor 1 [rad]
// Controller gains
const double motor1_KP = 13;                                                    // Position gain []
const double motor1_KI = 7;                                                     // Integral gain []
const double motor1_KD = 0.3;                                                   // Derivative gain []
double motor1_err_int = 0, motor1_prev_err = 0;
// Derivative filter coefficients
const double motor1_f_a1 = 0.25, motor1_f_a2 = 0.8;                             // Derivative filter coefficients []
const double motor1_f_b0 = 1, motor1_f_b1 = 2, motor1_f_b2 = 0.8;               // Derivative filter coefficients []
// Filter variables
double motor1_f_v1 = 0, motor1_f_v2 = 0;
 
// MOTOR 2
volatile double position2;                                                      // Position of motor 2 [rad]
volatile double reference2 = 0;                                                 // Desired rotation of motor 2 [rad]
double motor2Max = 2*pi*25/360;                                                 // Maximum rotation of motor 2 [rad]
double motor2Min = 2*pi*-28/360;                                                // Minimum rotation of motor 2 [rad]
// Controller gains
//const double motor2_KP = potmeter1*10;                                        // Position gain []
//const double motor2_KI = potmeter2*20;                                        // Integral gain []
const double motor2_KP = 13;                                                    // Position gain []
const double motor2_KI = 5;                                                     // Integral gain []
const double motor2_KD = 0.1;                                                   // Derivative gain []
double motor2_err_int = 0, motor2_prev_err = 0;
// Derivative filter coefficients
const double motor2_f_a1 = 0.25, motor2_f_a2 = 0.8;                             // Derivative filter coefficients []
const double motor2_f_b0 = 1, motor2_f_b1 = 2, motor2_f_b2 = 0.8;               // Derivative filter coefficients []
// Filter variables
double motor2_f_v1 = 0, motor2_f_v2 = 0;
 
// EMG //////////////////////////////////////////////////////////////////
Ticker emgLeft;
Ticker emgRight;
double emgTs = 0.5;
// Filters
BiQuadChain bqc;
BiQuad bq2_high(0.875182, -1.750364, 0.87518, -1.73472, 0.766004);
BiQuad bq3_notch(-1.1978e-16, 0.9561, 0.9780, -1.1978e-16, 0.9780);
BiQuad bq1_low(3.65747e-2, 7.31495e-2, 3.65747e-2, -1.390892, 0.537191);
// Right arm
volatile double emgFiltered_r;
volatile double filteredAbs_r;
volatile double emg_value_r;
volatile double onoffsignal_r;
volatile bool check_calibration_r=0;
volatile double avg_emg_r;
volatile bool active_r = false;
// Left arm 
volatile double emgFiltered_l;
volatile double filteredAbs_l;
volatile double emg_value_l;
volatile double onoffsignal_l;
volatile bool check_calibration_l=0;
volatile double avg_emg_l;
volatile bool active_l = false;
 
Ticker sampleTicker; 
const double sampleTs = 0.05;

volatile bool xdir = true, ydir = false;
volatile bool timer = false;
 
// FUNCTIONS ///////////////////////////////////////////////////////////////////
// BIQUAD FILTER FOR DERIVATIVE OF ERROR ///////////////////////////////////////
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;
    v2 = v1; v1 = v;
    return y;
}
 
// PID-CONTROLLER WITH FILTER //////////////////////////////////////////////////
double PID_Controller(double e, const double Kp, const double Ki,
 const double Kd, double Ts, double &e_int, double &e_prev, double &f_v1,
 double &f_v2, const double f_a1, const double f_a2, const double f_b0,
 const double f_b1, const double f_b2)
{
    // Derivative
    double e_der = (e - e_prev)/Ts;                                             // Calculate the derivative of error
    e_der = biquad(e_der, f_v1, f_v2, f_a1, f_a2, f_b0, f_b1, f_b2);            // Filter the derivative of error
    //e_der = bq1.step(e_der);
    e_prev = e;
    // Integral
    e_int = e_int + Ts*e;                                                       // Calculate the integral of error
    // PID
    //pc.printf("%f --> %f \r\n", e_der, e_derf);
    return Kp*e + Ki*e_int + Kd*e_der;
}
 
// MOTOR 1 /////////////////////////////////////////////////////////////////////
void RotateMotor1(double motor1Value)
{
    if(currentState == MOVING || currentState == HITTING)                       // Check if state is MOVING
    {
        if(motor1Value >= 0) motor1DirectionPin = 0;                            // Rotate motor 1 CW
        else motor1DirectionPin = 1;                                            // Rotate motor 1 CCW
        
        if(fabs(motor1Value) > 1) motor1MagnitudePin = 1;
        else motor1MagnitudePin = fabs(motor1Value);
    }
    else motor1MagnitudePin = 0;
}
 
// MOTOR 2 /////////////////////////////////////////////////////////////////////
void RotateMotor2(double motor2Value)
{
    if(currentState == MOVING || currentState == HITTING)                       // Check if state is MOVING
    {
        if(motor2Value >= 0) motor2DirectionPin = 1;                            // Rotate motor 1 CW
        else motor2DirectionPin = 0;                                            // Rotate motor 1 CCW
        
        if(fabs(motor2Value) > 1) motor2MagnitudePin = 1;
        else motor2MagnitudePin = fabs(motor2Value);
    }
    else motor2MagnitudePin = 0;
}
 
// MOTOR 1 PID-CONTROLLER //////////////////////////////////////////////////////
void Motor1Controller()
{
    if(currentState == MOVING)
    {
        position1 = radPerPulse * Encoder1.getPulses();
        position2 = radPerPulse * Encoder2.getPulses();
        //pc.printf("error %f \r\n", reference1 - position1);
        double motor1Value = PID_Controller(reference1 - position1, motor1_KP, 
         motor1_KI, motor1_KD, controller_Ts, motor1_err_int, motor1_prev_err,
         motor1_f_v1, motor1_f_v2, motor1_f_a1, motor1_f_a2, motor1_f_b0,
         motor1_f_b1, motor1_f_b2);
        //pc.printf("motor value %f \r\n",motor1Value);
        
        double motor2Value = PID_Controller(reference2 - position2, motor2_KP, 
         motor2_KI, motor2_KD, controller_Ts, motor2_err_int, motor2_prev_err,
         motor2_f_v1, motor2_f_v2, motor2_f_a1, motor2_f_a2, motor2_f_b0,
         motor2_f_b1, motor2_f_b2);
        
        //pc.printf("%f, %f \r\n", motor1Value, motor2Value);
        
        RotateMotor1(motor1Value);
        RotateMotor2(motor2Value);
    }
}
 
// MOTOR 2 PID-CONTROLLER //////////////////////////////////////////////////////
/*void Motor2Controller()
{
    position2 = radPerPulse * Encoder2.getPulses();
    double motor2Value = PID_Controller(reference2 - position2, motor2_KP, 
     motor2_KI, motor2_KD, controller2_Ts, motor2_err_int, motor2_prev_err,
     motor2_f_v1, motor2_f_v2, motor2_f_a1, motor2_f_a2, motor2_f_b0,
     motor2_f_b1, motor2_f_b2);
    RotateMotor2(motor2Value);
}
*/
// TURN OFF MOTORS /////////////////////////////////////////////////////////////
void TurnMotorsOff()
{
    motor1MagnitudePin = 0;
    motor2MagnitudePin = 0;
}
 

// EMG /////////////////////////////////////////////////////////////////////////
// Filter EMG signal of right arm
 
void filter_r(){                                      
    if(check_calibration_r==1){
        emg_value_r = emg_r.read();
        emgFiltered_r = bqc.step( emg_value_r );
        filteredAbs_r = abs( emgFiltered_r );
    if (avg_emg_r != 0){
        onoffsignal_r=filteredAbs_r/avg_emg_r;             //divide the emg_r signal by the max emg_r to calibrate the signal per person
      }
    }
}

// Filter EMG signal of left arm 
void filter_l(){                                      
    if(check_calibration_l==1){
        emg_value_l = emg_l.read();
        emgFiltered_l = bqc.step( emg_value_l );
        filteredAbs_l = abs( emgFiltered_l );
    if (avg_emg_l != 0){
        onoffsignal_l=filteredAbs_l/avg_emg_l;             //divide the emg_r signal by the avg_emg_l wat staat voor avg emg in gespannen toestand
      }
    }
}

// Check threshold right arm
void check_emg_r(){           
double filteredAbs_temp_r;
          
    if((check_calibration_l==1) &&(check_calibration_r==1)){ 
    for( int i = 0; i<250;i++){
               filter_r();
               filteredAbs_temp_r = filteredAbs_temp_r + onoffsignal_r;
               wait(0.0004); // 0.0004
               }    
               filteredAbs_temp_r = filteredAbs_temp_r/250;                                 
            if(filteredAbs_temp_r<=0.3){                         //if signal is lower then 0.5 the blue light goes on
                 led1.write(1);          //led 1 is rood en uit
                    
                    active_r = false;
            }
            else if(filteredAbs_temp_r > 0.3){                //if signal does not pass threshold value, blue light goes on
                    led1.write(0);
                    active_r = true;
            }
    }
}
    // Check threshold left arm
void check_emg_l(){        
double filteredAbs_temp_l;
          
    if((check_calibration_l)==1 &&(check_calibration_r==1) ){ 
    for( int i = 0; i<250;i++){
               filter_l();
               filteredAbs_temp_l = filteredAbs_temp_l + onoffsignal_l;
               wait(0.0004); // 0.0004
               }    
               filteredAbs_temp_l = filteredAbs_temp_l/250;                                 
            if(filteredAbs_temp_l<=0.3){                         //if signal is lower then 0.5 the blue light goes on
             //    led1.write(1);          //led 1 is rood en uit
                   led2.write(1);          //led 2 is blauw en aan
                    active_l = false;
            }
            else if(filteredAbs_temp_l > 0.3){                //if signal does not pass threshold value, blue light goes on
                 //   led1.write(0);
                   led2.write(0);
                    active_l = true;
            }
    }

}
 
// Calibrate right arm
int calibration_r(){
        led3.write(0);
       
        double signal_verzameling_r = 0;
        for(int n =0; n<5000;n++){   
           filter_r();
                              //read for 5000 samples as calibration
           emg_value_r = emg_r.read();
            emgFiltered_r = bqc.step( emg_value_r );
            filteredAbs_r = abs(emgFiltered_r);
         
          
           // signal_verzameling[n]=  filteredAbs_r;
             signal_verzameling_r = signal_verzameling_r + filteredAbs_r ;
             wait(0.0004);
             
              if (n == 4999){
                  avg_emg_r = signal_verzameling_r / n;
                  
                  }
            }  
          
             led3.write(1);
                 //pc.printf("calibratie rechts compleet\n\r");

        check_calibration_r=1;
    return 0;  
}
 
// Calibrate left arm
int calibration_l(){
        led3.write(0);
       
        double signal_verzameling_l= 0;
        for(int n =0; n<5000;n++){   
           filter_l();
                              //read for 5000 samples as calibration
           emg_value_l = emg_l.read();
            emgFiltered_l = bqc.step( emg_value_l );
            filteredAbs_l = abs(emgFiltered_l);
         
          
           // signal_verzameling[n]=  filteredAbs_r;
             signal_verzameling_l = signal_verzameling_l + filteredAbs_l ;
             wait(0.0004);
             
              if (n == 4999){
                  avg_emg_l = signal_verzameling_l / n;
                  
                  }
            }  
        led3.write(1);
        wait(1);
        check_calibration_l=1;
        
        //pc.printf("calibratie links compleet\n\r");
   // }
    return 0;  
}

// DETERMINE JOINT VELOCITIES //////////////////////////////////////////////////
void JointVelocities()
{
    if(currentState == MOVING)
    {
        position1 = radPerPulse * Encoder1.getPulses();
        position2 = radPerPulse * Encoder2.getPulses();
        
        if(xdir)
        {
            if(active_r && reference1 > motor1Min && reference2 < motor2Max) 
            {
                xVelocity = velocity;
                pc.printf("x positive \r\n");
            }
            else if(active_l && reference1 < motor1Max && reference2 > motor2Min)
            {
                xVelocity = -velocity;
                pc.printf("x negative \r\n");
            }
            else xVelocity = 0;
        }
        else if(ydir)
        {
            if(active_r && reference2 < motor2Max )//&& reference1 > motor2Min)
            {
                yVelocity = velocity;
                pc.printf("y positive \r\n");
            }
            else if(active_l && reference2 > motor2Min )//&& reference1 > motor2Min)
            {
                yVelocity = -velocity;
                pc.printf("y negative \r\n");
            }
            else yVelocity = 0;
        }
        
        //pc.printf("x %f, y %f \r\n", xVelocity, yVelocity);
        
        // Construct Jacobian
        double q[4];
        q[0] = position1, q[1] = -position1;
        q[2] = position2, q[3] = -position2;
        
        double T2[3];                                                               // Second column of the jacobian
        double T3[3];                                                               // Third column of the jacobian
        double T4[3];                                                               // Fourth column of the jacobian
        double T1[6];
        static const signed char b_T1[3] = { 1, 0, 0 };
        double J_data[6];
        
        T2[0] = 1.0;
        T2[1] = 0.365 * cos(q[0]);
        T2[2] = 0.365 * sin(q[0]);
        T3[0] = 1.0;
        T3[1] = 0.365 * cos(q[0]) + 0.2353720459187964 * sin((0.21406068356382149 +
         q[0]) + q[1]);
        T3[2] = 0.365 * sin(q[0]) - 0.2353720459187964 * cos((0.21406068356382149 +
         q[0]) + q[1]);
        T4[0] = 1.0;
        T4[1] = (0.365 * cos(q[0]) + 0.2353720459187964 * sin((0.21406068356382149 +
         q[0]) + q[1])) + 0.265 * sin((q[0] + q[1]) + q[2]);
        T4[2] = (0.365 * sin(q[0]) - 0.2353720459187964 * cos((0.21406068356382149 +
         q[0]) + q[1])) - 0.265 * cos((q[0] + q[1]) + q[2]);
         
        for (int i = 0; i < 3; i++)
        {
            T1[i] = (double)b_T1[i] - T2[i];
            T1[3 + i] = T3[i] - T4[i];
        }
        
        for (int i = 0; i < 2; i++) 
        {
            for (int j = 0; j < 3; j++)
            {
                J_data[j + 3 * i] = T1[j + 3 * i];
            }
        }
        
        // Here the first row of the Jacobian is cut off, so we do not take rotation into consideration
        // Note: the matrices from now on will we constructed rowwise
        double Jvelocity[4];
        Jvelocity[0] = J_data[1];
        Jvelocity[1] = J_data[4];
        Jvelocity[2] = J_data[2];
        Jvelocity[3] = J_data[5];
        
        // Creating the inverse Jacobian
        double Jvelocity_inv[4];                                                    // The inverse matrix of the jacobian
        double determ = Jvelocity[0]*Jvelocity[3]-Jvelocity[1]*Jvelocity[2];        // The determinant of the matrix
        Jvelocity_inv[0] = Jvelocity[3]/determ;
        Jvelocity_inv[1] = -Jvelocity[1]/determ;
        Jvelocity_inv[2] = -Jvelocity[2]/determ;
        Jvelocity_inv[3] = Jvelocity[0]/determ;
        
        // Now the velocity of the joints are found by giving the velocity of the end-effector and the inverse jacobian
        double msh[2];                                                              // This is the velocity the joints have to have
        msh[0] = xVelocity*Jvelocity_inv[0] + yVelocity*Jvelocity_inv[1];
        msh[1] = xVelocity*Jvelocity_inv[2] + yVelocity*Jvelocity_inv[3];
        
        if(reference1 + msh[0]*sampleTs > motor1Max) reference1 = motor1Max;
        else if(reference1 + msh[0]*sampleTs < motor1Min) reference1 = motor1Min;
        else reference1 = reference1 + msh[0]*sampleTs;
        
        if(reference2 + msh[1]*sampleTs > motor2Max) reference2 = motor2Max;
        else if(reference2 + msh[1]*sampleTs < motor2Min) reference2 = motor2Min;
        else reference2 = reference2 + msh[1]*sampleTs;
        
        scope.set(0,reference1);
        scope.set(1,position1);
        scope.set(2,reference2);
        scope.set(3,position2);
        scope.send();
        
        pc.printf("position 1 %f, 2 %f \r\n", position1/2/pi*360, position2/2/pi*360);
        pc.printf("reference 1 %f, 2 %f \r\n", reference1/2/pi*360, reference2/2/pi*360);
        //pc.printf("msh*Ts 1 %f, 2 %f \r\n\n", msh[0]*emg_Ts, msh[1]*emg_Ts);
        
    }
}

void StartTimer()
{
    timer = true;
    wait(3);
    timer = false;
}
 
// STATES //////////////////////////////////////////////////////////////////////
void ProcessStateMachine()
{
    switch(currentState)
    {
        case MOTORS_OFF:
        {
            // State initialization
            if(stateChanged)
            {
                pc.printf("Entering MOTORS_OFF \r\n"
                "Press button 1 to enter CALIBRATING \r\n");
                TurnMotorsOff();                                                // Turn motors off
                stateChanged = false;
            }
            
            // Home command
            if(!button1)
            {
                currentState = CALIBRATING;
                stateChanged = true;
                break;
            }
            break;
        }
        
        case CALIBRATING:
        {
            // State initialization
            if(stateChanged)
            {
                pc.printf("Entering CALIBRATING \r\n"
                "Press button 1 to enter MOVING \r\n");
                stateChanged = false;
                calibration_r();
                calibration_l();
                currentState = MOVING;
                stateChanged = true;
            }
            /*
            // Home command
            if(!button1)
            {
                currentState = MOVING;
                stateChanged = true;
                break;
            }
            */
            break;
        }
        
        case MOVING:
        {
            // State initialization
            if(stateChanged)
            {
                pc.printf("Entering MOVING \r\n");
                //"Press button 2 to enter HITTING \r\n");
                stateChanged = false;
            }
            
            if(active_l && active_r)
            {
                if(!timer)
                {
                    active_l = false;
                    active_r = false;
                    xdir = !xdir;
                    ydir = !ydir;
                    led4 = !led4;
                    led5 = !led5;
                    if(active_l)pc.printf("links active");
                    else pc.printf("links inactive");
                    StartTimer();
                }
            }
            
            // Hit command    
            /*if(!button2)
            {
                currentState = HITTING;
                stateChanged = true;
                break;
            }
            */
            break;
        }
        
        case HITTING:
        {
            // State initialization
            if(stateChanged)
            {
                //pc.printf("Entering HITTING \r\n");
                stateChanged = false;
                //HitBall();                                                    // Hit the ball
                currentState = MOVING;
                stateChanged = true;
                break;
            }
            break;
        }
        
        default:
        {
            TurnMotorsOff();                                                    // Turn motors off for safety
            break;
        }
    }
}
 
// MAIN FUNCTION ///////////////////////////////////////////////////////////////
int main()
{
    // Serial communication
    pc.baud(115200);
    
    led1.write(1);
    led2.write(1);
    led3.write(1);
    led4.write(1);
    led5.write(0);
    
    pc.printf("START \r\n");
    
    bqc.add( &bq1_low ).add( &bq2_high ).add( &bq3_notch );
    
    sampleTicker.attach(&JointVelocities, sampleTs);                                 // Ticker to sample EMG
    controllerTicker.attach(&Motor1Controller, controller_Ts);                // Ticker to control motor 1 (PID)
    emgRight.attach(&check_emg_r, emgTs);         //continously execute the motor controller
    emgLeft.attach(&check_emg_l, emgTs);
    
    motor1MagnitudePin.period_ms(1);
    motor2MagnitudePin.period_ms(1);
    TurnMotorsOff();
    
    while(true)
    {
        ProcessStateMachine();                                                  // Execute states function
    }
}