File content as of revision 11:2ffae0f2110a:

#include "mbed.h"
#include "math.h"
#include "MODSERIAL.h"
#include "QEI.h"
#include "BiQuad.h"
#include "MovingAverage.h"
#define NSAMPLE 200

//states
enum States {Waiting, Homing, Emergency, EMGCal, MotorCal, Operation, Demo};

// Global variables
States CurrentState;
Ticker TickerLoop;
Timer TimerLoop;

//Communication
MODSERIAL pc(USBTX,USBRX);
QEI Encoder1(D10,D11,NC,32);    // Encoder motor q1 (arm)
QEI Encoder2(D12,D13,NC,32);    // Encoder motor q2 (end-effector)

//EMG settings
AnalogIn emg0(A0); //Biceps Left
AnalogIn emg1(A1); //Biceps Right
MovingAverage <double>Movag_LB(NSAMPLE,0.0); //Make Moving Average, Define NSAMPLE above
MovingAverage <double>Movag_RB(NSAMPLE,0.0);

// filters
//Make Biquad filters Left(a0, a1, a2, b1, b2)
BiQuadChain bqc1; //chain voor High Pass en Notch
BiQuad bq1(0.39131200825291007, -0.7826240165058201, 0.39131200825291007, -0.36950493743858204, 0.1957430955730582); //High Pass Filter
BiQuad bq2(9.91104e-01, -1.60364e+00, 9.91104e-01, -1.60364e+00, 9.82207e-01); //Notch Filter
//Make Biquad filters Right
BiQuadChain bqc2; //chain voor High Pass en Notch
BiQuad bq3(0.39131200825291007, -0.7826240165058201, 0.39131200825291007, -0.36950493743858204, 0.1957430955730582); //High Pass Filter
BiQuad bq4(9.91104e-01, -1.60364e+00, 9.91104e-01, -1.60364e+00, 9.82207e-01); //Notch Filter


//Global pin variables Motors 1
PwmOut PwmPin1(D5);
DigitalOut DirectionPin1(D4);

//Global pin variables Motors 2
PwmOut PwmPin2(D6);
DigitalOut DirectionPin2(D7);

//Output LED
DigitalOut LedRed (LED_RED);
DigitalOut LedGreen (LED_GREEN);
DigitalOut LedBlue (LED_BLUE);

// Buttons
DigitalIn BUTSW2(SW2);
DigitalIn BUTSW3(SW3);
DigitalIn BUT1(D8);
DigitalIn BUT2(D9);

//Constant variables
const float L0 = 0.1; // Distance between origin frame and joint 1 [m[
const float L1 = 0.326; // Length link 1 (shaft to shaft) [m]
const float L2 = 0.209; // Length link 2 (end-effector length) [m]
const double Ts = 0.002; //Sampling time 500 Hz


// variables
//Motor calibration
bool NextMotorFlag = false;

//EMG
bool EMGBoolLeft; // Boolean EMG 1 (left)
bool EMGBoolRight; // Boolean EMG 2 (right)
double LeftBicepsOut; // Final value left of processed EMG
double RightBicepsOut; // Final value right of processed EMG
double ThresholdLeft = 1; //Threshold to compare with value (start off with max value = 1)
double ThresholdRight = 1; //Threshold to compare with value (start off with max value = 1)

// Reference positions
float q1Ref = 0;
float q2Ref = 0;

//Motors
float q1 = 0; // Current angle of motor 1 (arm)
float q2 = 0; // Current angle of motor 2 (end-effector)
float qArm = 0; //Current angle of arm
float qEndEff = 0; //Current angle of end-effector
float MotorValue1; // Inputvalue to set motor 1
float MotorValue2; // Inputvalue to set motor 2

//Inverse kinematics
float VdesX; // Desired velocity in x direction
float VdesY; // Desired velocity in y direction
float Error1; // Difference in reference angle and current angle motor 1
float Error2; // Difference in reference angle and current angle motor 2
int xDir;
int yDir;
float RatioGears = 134.0/30.0;
float RatioPulleys = 87.4/27.5;
//Print to screen
int PrintFlag = false;
int CounterPrint = 0;


//------------------------------------------------------------------------------
//------------------------------------------------------------------------------

void PrintToScreen()
{
    CounterPrint++;
    if (CounterPrint == 100) {
        PrintFlag = true;
        CounterPrint = 0;
    }
}

// Function to set motors off
void SetMotorsOff()
{
    // Turn motors off
    PwmPin1 = 0;
    PwmPin2 = 0;

}

// Function for processing EMG
void ProcessingEMG()
{
    //Filter Left Biceps
    double LB_Filter_1 = bqc1.step(emg0.read()); //High Pass + Notch
    double LB_Rectify = fabs(LB_Filter_1); //Rectify Signal
    Movag_LB.Insert(LB_Rectify); //Moving Average
    LeftBicepsOut = Movag_LB.GetAverage(); //Get final value

    //Filter Right Biceps
    double RB_Filter_1 = bqc2.step(emg1.read()); //High Pass + Notch
    double RB_Rectify = fabs(RB_Filter_1); //Rectify Signal
    Movag_RB.Insert(RB_Rectify); //Moving Average
    RightBicepsOut = Movag_RB.GetAverage();  //Get final value

    if (LeftBicepsOut > ThresholdLeft) {
        EMGBoolLeft = true;
    } 
    else {
        EMGBoolLeft = false;
    }
    if (RightBicepsOut > ThresholdRight) {
        EMGBoolRight = true;
    } 
    else {
        EMGBoolRight = false;
    }

}

void MeasureAll()
{
    //Processing and reading EMG
    ProcessingEMG();

    //Measure current motor angles
    float Counts1 = Encoder1.getPulses();
    float Counts2 = Encoder2.getPulses();
    q1 = Counts1/8400*(2*6.28318530718); //angle motor 1 (Times 2 to compensate for endcoding X4 --> X2)
    q2 = Counts2/8400*(2*6.28318530718); // angle motor 2 (Times 2 to compensate for endcoding X4 --> X2)
    
    
    qArm = -1*q1/RatioGears; //Adjust for opposite direction due to gears
    qEndEff = q2/RatioPulleys; 



}

// Function to set desired cartesian velocities of end-effector
void Vdesired()
{
    xDir = 1-BUT1.read();
    yDir = 1-BUT2.read();
    double Vconst = 0.05; // m/s (3 cm per second)
    VdesX = xDir*Vconst; // Left biceps is X-direction
    VdesY = -1*yDir*Vconst; // Right biceps is minus Y-direction
}

// Inverse Kinematics
void InverseKinematics()
{
    // matrix inverse Jacobian
    double InvJac11 = (L2*(cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm)) + cos(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) - L0*cos(qArm) - L1*cos(qArm) + (cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff))*(L0 + L1) + sin(qArm)*sin(qEndEff)*(L0 + L1))/((L2*(cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff)) - sin(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) + L0*sin(qArm) - (cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm))*(L0 + L1) + cos(qArm)*sin(qEndEff)*(L0 + L1))*(L2*(cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm)) + cos(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) - L0*cos(qArm) - L1*cos(qArm) + (cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff))*(L0 + L1) + sin(qArm)*sin(qEndEff)*(L0 + L1)) - (L2*(cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm)) + cos(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) - L0*cos(qArm) + (cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff))*(L0 + L1) + sin(qArm)*sin(qEndEff)*(L0 + L1))*(L2*(cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff)) - sin(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) + L0*sin(qArm) + L1*sin(qArm) - (cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm))*(L0 + L1) + cos(qArm)*sin(qEndEff)*(L0 + L1)));
    double InvJac12 = -(L2*(cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff)) - sin(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) + L0*sin(qArm) + L1*sin(qArm) - (cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm))*(L0 + L1) + cos(qArm)*sin(qEndEff)*(L0 + L1))/((L2*(cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff)) - sin(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) + L0*sin(qArm) - (cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm))*(L0 + L1) + cos(qArm)*sin(qEndEff)*(L0 + L1))*(L2*(cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm)) + cos(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) - L0*cos(qArm) - L1*cos(qArm) + (cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff))*(L0 + L1) + sin(qArm)*sin(qEndEff)*(L0 + L1)) - (L2*(cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm)) + cos(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) - L0*cos(qArm) + (cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff))*(L0 + L1) + sin(qArm)*sin(qEndEff)*(L0 + L1))*(L2*(cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff)) - sin(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) + L0*sin(qArm) + L1*sin(qArm) - (cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm))*(L0 + L1) + cos(qArm)*sin(qEndEff)*(L0 + L1)));
    double InvJac21 = -(L2*(cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm)) + cos(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) - L0*cos(qArm) + (cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff))*(L0 + L1) + sin(qArm)*sin(qEndEff)*(L0 + L1))/((L2*(cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff)) - sin(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) + L0*sin(qArm) - (cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm))*(L0 + L1) + cos(qArm)*sin(qEndEff)*(L0 + L1))*(L2*(cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm)) + cos(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) - L0*cos(qArm) - L1*cos(qArm) + (cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff))*(L0 + L1) + sin(qArm)*sin(qEndEff)*(L0 + L1)) - (L2*(cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm)) + cos(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) - L0*cos(qArm) + (cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff))*(L0 + L1) + sin(qArm)*sin(qEndEff)*(L0 + L1))*(L2*(cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff)) - sin(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) + L0*sin(qArm) + L1*sin(qArm) - (cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm))*(L0 + L1) + cos(qArm)*sin(qEndEff)*(L0 + L1)));
    double InvJac22 = (L2*(cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff)) - sin(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) + L0*sin(qArm) - (cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm))*(L0 + L1) + cos(qArm)*sin(qEndEff)*(L0 + L1))/((L2*(cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff)) - sin(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) + L0*sin(qArm) - (cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm))*(L0 + L1) + cos(qArm)*sin(qEndEff)*(L0 + L1))*(L2*(cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm)) + cos(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) - L0*cos(qArm) - L1*cos(qArm) + (cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff))*(L0 + L1) + sin(qArm)*sin(qEndEff)*(L0 + L1)) - (L2*(cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm)) + cos(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) - L0*cos(qArm) + (cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff))*(L0 + L1) + sin(qArm)*sin(qEndEff)*(L0 + L1))*(L2*(cos(qArm)*cos(qEndEff) - sin(qArm)*sin(qEndEff)) - sin(qArm)*(L0 + L1 - cos(qEndEff)*(L0 + L1)) + L0*sin(qArm) + L1*sin(qArm) - (cos(qArm)*sin(qEndEff) + cos(qEndEff)*sin(qArm))*(L0 + L1) + cos(qArm)*sin(qEndEff)*(L0 + L1)));



    double q1DotRef = (InvJac11*VdesX + InvJac12*VdesY); //reference angular velocity motor 1
    double q2DotRef = (InvJac21*VdesX + InvJac22*VdesY); //reference angular velocity motor 2

    q1Ref += q1DotRef*Ts; // set new reference position motor angle 1
    q2Ref += q2DotRef*Ts; // set new reference position motor angle 1
}

//State machine
void StateMachine()
{
    switch (CurrentState) {
        case Waiting:
            SetMotorsOff();
            Encoder1.reset();
            q1Ref = 0;
            q1 = 0;
            Error1 = 0;
            Encoder2.reset();
            q2Ref = 0;
            q2 = 0;
            Error2 = 0;

            LedRed = 0;
            LedGreen = 0;
            LedBlue = 1; //Yellow

            if (BUT2 == false) {
                CurrentState = EMGCal;
                TimerLoop.reset();
            }

            break;

        case Homing:
            LedRed = 0;
            LedGreen = 0;
            LedBlue = 0; //White
            static bool Switch2Demo = false;
            static bool Switch2OP = false;
            if (BUT2 == false) 
            {
                Switch2Demo = true;
                TimerLoop.reset();
            }
            if ((Switch2Demo == true) && (TimerLoop.read()>=2.0))
            {
                CurrentState = Demo;
                Switch2Demo = false;   
            }
            if (BUT1 == false) 
            {
                Switch2OP = true;
                TimerLoop.reset();
            }
            if ((Switch2OP == true) && (TimerLoop.read()>=2.0))
            {
                CurrentState = Operation;
                Switch2OP = false;   
            }
            
            
            break;

        case Emergency:
            LedRed = 0;
            LedGreen = 1;
            LedBlue = 1; //Red
            break;

        case EMGCal:
            LedRed = 0;
            LedGreen = 1;
            LedBlue = 0; //Pink
            static double MaxLeft = 0;
            static double MaxRight = 0;

            if(LeftBicepsOut > MaxLeft) {
                MaxLeft = LeftBicepsOut;
                ThresholdLeft = abs(0.2000*MaxLeft);
                TimerLoop.reset();
            }

            if(RightBicepsOut > MaxRight) {
                MaxRight = RightBicepsOut;
                ThresholdRight = abs(0.2000*MaxRight);
                TimerLoop.reset();
            }

            if (BUT1 == false) {
                //ThresholdLeft = abs(0.15000*MaxLeft);
                //ThresholdRight = abs(0.15000*MaxRight);
            }
            if ((ThresholdLeft<0.9) && (ThresholdRight <0.9) && (TimerLoop.read() >= 5.0)) {
                TimerLoop.reset();
                CurrentState = MotorCal;
            }
            break;

        case MotorCal:
            LedRed = 1;
            LedGreen = 0;
            LedBlue = 0; //Turqoise
            if (NextMotorFlag == false) {
                if (BUT1==false) {
                    q1Ref += 0.0005*(6.2830);
                }
                if (BUTSW3 == false) {
                    q1Ref = 0;
                    Encoder1.reset();
                }
                if (BUT2 == false) {
                    q1Ref -=0.0005*(6.2830);
                }
                if (BUTSW2 == false) {
                    if (q1Ref>=-0.52*(6.2830)) {
                        q1Ref -=0.0005*(6.2830);
                    } else {
                        TimerLoop.reset();
                        NextMotorFlag = true;
                    }

                } //End of if (BUTSW2 == false)
            } //End of if (NextMotorFlag == false)

            else if ((NextMotorFlag == true) && (TimerLoop.read()>= 2)) {
                if (BUT1==false) {
                    q2Ref += 0.0005*(6.2830);
                }
                if (BUTSW3 == false) {
                    q2Ref = 0;
                    Encoder2.reset();
                }
                if (BUT2 == false) {
                    q2Ref -= 0.0005*(6.2830);
                }
                if (BUTSW2 == false) {
                    if (q2Ref<=0.733*(6.2830)) {
                        q2Ref +=0.0005*(6.2830);
                    } else {
                        CurrentState = Homing;
                        Encoder1.reset();
                        Encoder2.reset();
                        q1Ref = 0;
                        q2Ref = 0;
                        Error1 = 0;
                        Error2 = 0;
                        q1 = 0;
                        q2 = 0;
                        TimerLoop.reset();
                    }
                } // end of if (BUTSW2) statement
            }// end of else if statement

            break;

        case Operation:
            LedRed = 1;
            LedGreen = 0;
            LedBlue = 1; //Green
            break;

        case Demo:
            LedRed = 1;
            LedGreen = 1;
            LedBlue = 0; //Blue

            //if (TimerLoop.read() <= 5.0)
            //{
            // if((EMGBoolLeft == true) || (EMGBoolRight == true))
            //{
            TimerLoop.reset();
            Vdesired();
            InverseKinematics();
            //}
            //}
            //else
            //{
            // q1Ref = 0;
            // q2Ref = 0;
            // Error1 = q1Ref - q1;
            // Error2 = q2Ref - q2;
            //  if ((Error1 <= 0.1) && (Error2 <= 0.1))
            //{
            //    TimerLoop.reset();
            // }

            break;


    } //End of switch
} // End of stateMachine function

//------------------------------------------------------------------------------

void SetErrors()
{
    if (CurrentState == Demo)
    {
    Error1 = -1*RatioGears*(q1Ref - qArm);
    Error2 = RatioPulleys*(q2Ref - qEndEff);
    }
    else
    Error1 = q1Ref - q1;
    Error2 = q2Ref - q2;
    
}
//------------------------------------------------------------------------------
// controller motor 1
void PID_Controller1(double Err1)
{
    double Kp = 19.8; // proportional gain
    double Ki = 3.98;//integral gain
    double Kd = 1.96;  //derivative gain
    static double ErrorIntegral = 0;
    static double ErrorPrevious = Err1;
    static BiQuad LowPassFilter(0.0640, 0.1279, 0.0640, -1.1683, 0.4241);

    //Proportional part:
    double u_k = Kp * Err1;

    //Integral part:
    ErrorIntegral = ErrorIntegral + Err1*Ts;
    double u_i = Ki * ErrorIntegral;

    //Derivative part:
    double ErrorDerivative = (Err1 - ErrorPrevious)/Ts;
    double FilteredErrorDerivative = LowPassFilter.step(ErrorDerivative);
    double u_d = Kd * FilteredErrorDerivative;
    ErrorPrevious = Err1;

    MotorValue1 =  u_k + u_i + u_d; //This will become the MotorValue to set motor 1
}

// controller motor 2
void PID_Controller2(double Err2)
{
    double Kp = 11.1; // proportional gain
    double Ki = 2.24;//integral gain
    double Kd = 1.1;  //derivative gain
    static double ErrorIntegral = 0;
    static double ErrorPrevious = Err2;
    static BiQuad LowPassFilter(0.0640, 0.1279, 0.0640, -1.1683, 0.4241);

    //Proportional part:
    double u_k = Kp * Err2;

    //Integral part:
    ErrorIntegral = ErrorIntegral + Err2*Ts;
    double u_i = Ki * ErrorIntegral;

    //Derivative part:
    double ErrorDerivative = (Err2 - ErrorPrevious)/Ts;
    double FilteredErrorDerivative = LowPassFilter.step(ErrorDerivative);
    double u_d = Kd * FilteredErrorDerivative;
    ErrorPrevious = Err2;

    MotorValue2 =  u_k + u_i + u_d; //This will become the MotorValue to set motor 2
}

// Main function for motorcontrol
void MotorControllers()
{
    PID_Controller1(Error1);
    PID_Controller2(Error2);

}
//------------------------------------------------------------------------------

//Ticker function set motorvalues
void SetMotors()
{
// Motor 1
    if (MotorValue1 >=0) { // set direction
        DirectionPin1 = 1;
    } else {
        DirectionPin1 = 0;
    }

    if (fabs(MotorValue1)>1) { // set duty cycle
        PwmPin1 = 1;
    } else {
        PwmPin1 = fabs(MotorValue1);
    }

// Motor 2
    if (MotorValue2 >=0) { // set direction
        DirectionPin2 = 1;
    } else {
        DirectionPin2 = 0;
    }

    if (fabs(MotorValue2)>1) { // set duty cycle
        PwmPin2 = 1;
    } else {
        PwmPin2 = fabs(MotorValue2);
    }

}




//-----------------------------------------------------------------------------


// Execution function
void LoopFunction()
{
    MeasureAll();
    StateMachine();
    SetErrors();
    MotorControllers();
    SetMotors();
    PrintToScreen();
}

int main()
{
    PwmPin1.period_us(60);
    PwmPin2.period_us(60);
    pc.baud(115200);
    pc.printf("Hi I'm PTR, you can call me Peter!\r\n");
    TimerLoop.start(); // start Timer
    CurrentState = Waiting; // set initial state as Waiting
    bqc1.add( &bq1 ).add( &bq2 ); //make BiQuadChain EMG left
    bqc2.add( &bq3 ).add( &bq4 ); //make BiQuadChain EMG right
    TickerLoop.attach(&LoopFunction, 0.002f); //ticker for function calls 500 Hz

    while (true) {
        if (PrintFlag == true) {
            pc.printf("xButton = %i, yButton = %i, q1Ref = %f, q1 = %f, q2Ref = %f, q2= %f Error1 = %f, Error2 = %f\r",xDir,yDir,q1Ref,q1,q2Ref,q2,Error1,Error2);
        }
    }

}