File content as of revision 3:d16182dd3a2a:

#include "mbed.h"
#include "FastPWM.h"
#include "MODSERIAL.h"
#include "Matrix.h"
#include "QEI.h"
#include <math.h>
MODSERIAL pc(USBTX, USBRX);
DigitalOut motor1Direction(D7);
DigitalOut motor2Direction(D4);
DigitalOut Led(LED_GREEN);
DigitalIn button2(SW3); //dit is nog button op mbed bor
FastPWM motor1PWM(D6);
FastPWM motor2PWM(D5);
AnalogIn potMeter1(A4);
AnalogIn potMeter2(A5);
QEI Encoder1 (D12, D13, NC, 64, QEI::X4_ENCODING);
QEI Encoder2 (D10, D11, NC, 64, QEI::X4_ENCODING);

// Tickers
Ticker potmeterTicker;

//------------------------------------------------------------------------------
//Global Variables
 
double currentPosition1 = 0.0;          // Starting position of motor 1 [rad]
double currentPosition2 = -(0.5*3.14);  // Starting position of motor 2 wrt motor 1 [rad]
int a = 0;

//Inverse Kinematics
const double L0 = 0.1;              // Horizontal length from base to first joint [m]   NAMETEN!!
const double L1 = 0.3;              // Length link 1 [m]                                NAMETEN!!
const double L2 = 0.3;              // Length link 2 [m]                                NAMETEN!!
const double L3 = 0.1;              // Vertical length from base to first joint [m]     NAMETEN!
volatile double q1 = 0.0;           // Starting reference angle of first link [rad]
volatile double q2 = -(0.5*3.14);   // Starting reference angle of second link wrt first link [rad]
double t = 2.0;                     // Time interval [s]                                SHOULD BE REPLACED          SAMPLING TIJD!!
volatile double vx_des = 0.0;       // Starting velocity in x-direction [rad/s]
volatile double vy_des = 0.0;       // Starting velocity in y-direction [rad/s]
Matrix Q_set(2,1);                  // Setting a matrix for storing the angular velocities [rad/sec]
Matrix J(2,2);                      // Setting a matrix for the Jacobian
Matrix V(2,1);                      // Setting a matrix for storing the EMG-measured velocities

// Motor Control
volatile double potMeterPosition1 = 0.0;
//volatile double potMeterPosition2 = 0.0;
volatile double motorValue1 = 0.01;
volatile double motorValue2 = 0.01;
volatile double Kp = 0.34; //dit maken we variabel, dit zorgt voor een grote of kleine overshoot
volatile double Ki = 0.0; //dit moeten we bepalen met een plot bijvoorbeeld
volatile double Kd = 0.0;
volatile double Ts = 0.01;                      //                                                          SAMPLING TIJD!!


//------------------------------------------------------------------------------
// Potmeter values TO DETERMINE VX_DES, VY_DES
void GetPotMeterVelocity1()  //Potmeter standard to control X-DIRECTION
{
    double potMeter1In = potMeter1.read();
    //vx_des = 0.5*3.14*potMeter1In - 0.25*3.14 ; // Reference value y, scaled to -0.25 to 0.25 revolutions
    vx_des = 3.7;
    //return vx_des;
}

double SwitchPotmeterVelocity1() {  //Button has been pressed,
    vy_des = vx_des;
    return vy_des;
}

//------------------------------------------------------------------------------
// KINEMATIC FUNCTIONS

Matrix ComputeJ(void)
{
    double a = -sin(q2)/(L1*cos(q1)*sin(q2)-L1*cos(q2)*sin(q1));
    double b = cos(q2)/(L1*cos(q1)*sin(q2)-L1*cos(q2)*sin(q1));
    double c = (L1*sin(q1)+L2*sin(q2))/(L1*L2*cos(q1)*sin(q2)-L1*L2*cos(q2)*sin(q1));
    double d = -(L1*cos(q1)+L2*cos(q2))/(L1*L2*cos(q1)*sin(q2)-L1*L2*cos(q2)*sin(q1));
    J << a << b
      << c << d;
    return J;
}

Matrix ComputeV(void)
{
    V.add(1,1,vx_des); // Add desired x-velocity in V
    V.add(2,1,vy_des); // Add desired y-velocity in V
    return V;
}

double IntegrateQ1()
{
    q1  = q1 + (Q_set(1,1))*t;    // new value for q1
    return q1;
}

double IntegrateQ2()
{
    q2 = q2 + (Q_set(2,1))*t;    // new value for q2
    return q2;
}

Matrix ComputeQ_set(void)
{
    float a = J(1,1);
    float b = J(1,2);
    float c = J(2,1);
    float d = J(2,2);
    float e = V(1,1);
    float f = V(2,1);
    float first_row = a*e + b*f;
    float second_row = c*e + d*f;
    Q_set.add(1,1,first_row);
    Q_set.add(2,1,second_row);
    return Q_set;
}

double ErrorInverseKinematics1()
{
    double errorIK1 = q1 - currentPosition1;
    return errorIK1;
}
 
double ErrorInverseKinematics2()
{
    double errorIK2 = q2 - currentPosition2;
    return errorIK2;
}
//------------------------------------------------------------------------------
// MOTOR PART
//Encoder Posities
double MeasureEncoderPosition1()        // Read current position of motor 1, returns value in [rad]
{
    int counts1i = Encoder1.getPulses();
    double counts1 = counts1i*1.0f;
    double measuredPosition1 = (counts1/8400)*6.28; //Rotational position in radians
    return measuredPosition1;
}

double MeasureEncoderPosition2()        // Read current postion of motor 2, returns value in [rad]
{
    int counts2i = Encoder2.getPulses();
    double counts2 = counts2i*1.0f;
    double measuredPosition2 = (counts2/8400)*6.28; //Rotational position in radians
    return measuredPosition2;
}

double FeedbackControl1(double Error1)
{
    static double Error_integral1 = 0;
    static double Error_prev1 = Error1;
    // Proportional part:
    double u_k1 = Kp * Error1;
    // Integral part:
    Error_integral1 = Error_integral1 + Error1 * Ts;
    double u_i1 = Ki * Error_integral1;
    // Derivative part:
    double Error_derivative1 = (Error1 - Error_prev1)/Ts;
    double u_d1 = Kd * Error_derivative1;
    Error_prev1 = Error1;
    // Sum all parts and return it
    return u_k1 + u_i1 + u_d1; //motorValue
}

double FeedbackControl2(double Error2)
{
    static double Error_integral2 = 0;
    static double Error_prev2 = Error2;
    // Proportional part:
    double u_k2 = Kp * Error2;
    // Integral part:
    Error_integral2 = Error_integral2 + Error2 * Ts;
    double u_i2 = Ki * Error_integral2;
    // Derivative part:
    double Error_derivative2 = (Error2 - Error_prev2)/Ts;
    double u_d2 = Kd * Error_derivative2;
    Error_prev2 = Error2;
    // Sum all parts and return it
    return u_k2 + u_i2 + u_d2; //motorValue
}

void SetMotor1(double motorValue1)
{
    // Given -1<=motorValue<=1, this sets the PWM and direction
    // bits for motor 1. Positive value makes motor rotating
    // clockwise. motorValues outside range are truncated to
    // within range
    // 0 = clockwise motor direction
    // 1 = counterclockwise motor direction
    if (motorValue1 >=0) {
        motor1Direction=0;
    } else {
        motor1Direction=1;
    }
    if (fabs(motorValue1)>1) {
        motor1PWM = 1;
    } else {
        motor1PWM = fabs(motorValue1);
    }
}

void SetMotor2(double motorValue2)
{
    // Given -1<=motorValue<=1, this sets the PWM and direction
    // bits for motor 1. Positive value makes motor rotating
    // clockwise. motorValues outside range are truncated to
    // within range
    // 0 = counterclockwise motor direction
    // 1 = clockwise motor direction
    if (motorValue2 >=0) {
        motor2Direction=1;
    } else {
        motor2Direction=0;
    }
    if (fabs(motorValue2)>1) {
        motor2PWM = 1;
    } else {
        motor2PWM = fabs(motorValue2);
    }
}

/*void MeasureAndControl1(void)
{
    // This function determines the desired velocity, measures the
    // actual velocity, and controls the motor with
    // a simple Feedback controller. Call this from a Ticker.
    MeterPosition1 = q1;
    currentPosition1 = MeasureEncoderPosition1();
    motorValue1 = FeedbackControl1(potMeterPosition1 - currentPosition1);
    SetMotor1(motorValue1);
}

void MeasureAndControl2(void)
{
    // This function determines the desired velocity, measures the
    // actual velocity, and controls the motor with
    // a simple Feedback controller. Call this from a Ticker.
    potMeterPosition2 = q2;
    currentPosition2 = MeasureEncoderPosition2();
    motorValue2 = FeedbackControl2(potMeterPosition2 - currentPosition2);
    SetMotor2(motorValue2);
}*/

//------------------------------------------------------------------------------
// MAIN
int main()
{
    pc.baud(115200);
    potmeterTicker.attach(GetPotMeterVelocity1, 0.01);
    
    while (true) {
        currentPosition1 = MeasureEncoderPosition1();   // You want to know the current angle of the motors to get the right Jacobian
        currentPosition2 = MeasureEncoderPosition2();   // You want to know the current angle of the motors to get the right Jacobian
        J = ComputeJ();                                 // Compute matrix J (inverse Jacobian, and Twist is already left out)
        V = ComputeV();                                 // Compute matrix V (stores the desired velocities obtained from the EMG signal)
        Q_set = ComputeQ_set();                         // Compute Q_set (stores Q1 and Q2)
        q1 = IntegrateQ1();                                  // Compute required angle to go to desired position of end-effector
        q2 = IntegrateQ2();                                  // Compute required angle to go to desired position of end-effector
        if (q1 < 1.047) {                               // q1 can only be smaller than 1.047 rad
            q1 = q1;
        } else {                                        // If value of q1 is greater than 1.047 rad, then stay at maximum angle
            q1 = 1.047;
        }
        if (q2 < 0.61) {                                // q2 cannot be smaller than 0.61 rad
            q2 = 0.61;                                  // Stay at mimimum angle
        } else if (q2 > 1.57) {                         // q2 cannot be greater than 1.57 rad
            q2 = 1.57;                                  // Stay at maximum angle
        } else {                                        // If q2 is in the right range, let calculated q2 be q2
            q2 = q2;
        }
        // Determine error and add PID control
        double errorIK1 = ErrorInverseKinematics1();       // Determine difference between current angle motor 1 and desired angle
        double errorIK2 = ErrorInverseKinematics2();        // Determine difference between current angle motor 2 and desired angle
        // Determine motorValues
        motorValue1 = FeedbackControl1(errorIK1);                       // Calculate motorValue1
        motorValue2 = FeedbackControl2(errorIK2);                       // Calculate motorValue2
        // Make Motor move
        SetMotor1(motorValue1);
        SetMotor2(motorValue2);

        // Press button to switch velocity direction
        //if (!button2.read()) {
        if (!button2.read()) { //button2 blijven indrukken
            //SwitchPotmeterVelocity1();
            vy_des=vx_des;
            vx_des=0;
        } else {
            vy_des=0;
        }
        pc.printf("vx_des = %f \t vy_des = %f \r\n", vx_des, vy_des);
        pc.printf("Error IK1 = %f \t Error IK2 = %f \r\n", errorIK1, errorIK2);
        pc.printf("MotorValue 1 = %f \t MotorValue 2 = %f \r\n", motorValue1, motorValue2);
        pc.printf("q1 Qset = %f \t q2 Qset = %f \r\n", Q_set(1,1), Q_set(2,1));
        wait(0.01);
    }
}