File content as of revision 32:d651c23bbb77:

#include "mbed.h"
#include "HIDScope.h"
#include "QEI.h"
#include "MODSERIAL.h"
#include "BiQuad.h"
#include "FastPWM.h"
#define  M_PI 3.14159265358979323846  /* pi */
#include <math.h>
#include "Servo.h"
#include <cmath>
#include <complex>

Serial pc(USBTX, USBRX);

// TICKERS
Ticker loop_ticker;

// BENODIGD VOOR PROCESS STATE MACHINE
enum states {Motors_off, Calib_motor, Calib_EMG, Homing, Operation_mode};
states currentState = Motors_off;
bool stateChanged = true; // Make sure the initialization of first state is executed

// INPUTS
DigitalIn Power_button_pressed(D1); // Geen InterruptIn gebruiken!
DigitalIn Emergency_button_pressed(D2);
DigitalIn Motor_calib_button_pressed(SW2);

AnalogIn EMG_biceps_right_raw (A0);
AnalogIn EMG_biceps_left_raw (A1);
AnalogIn EMG_calf_raw (A2);

QEI Encoder1(D12, D13, NC, 8400, QEI::X2_ENCODING); //Checken of die D12, D9 etc wel kloppen, 8400= gear ratio x 64
QEI Encoder2(D9, D10, NC, 8400, QEI::X2_ENCODING);

// OUTPUTS
PwmOut motor1(D6);  // Misschien moeten we hiervoor DigitalOut gebruiken, moet
PwmOut motor2(D5);  // samen kunnen gaan met de servo motor

DigitalOut motor1_dir(D7);
DigitalOut motor2_dir(D4);

// VARIABELEN VOOR ENCODER, MOTORHOEK ETC.
int pulses_M1;
int pulses_M2;
int counts1;
int counts2;
const double conversion_factor = (2.0*M_PI)/(64.0*131.25*2.0);
double theta_h_1_rad;
double theta_h_2_rad;

// DEFINITIES VOOR FILTERS

// BICEPS-RECHTS
// Definities voor eerste BiQuadChain (High-pass en Notch)
BiQuadChain bqcbr;
BiQuad bqbr1(0.8006, -1.6012, 0.8006, -1.5610, 0.6414); // High-pass
BiQuad bqbr2(1, -1.6180, 1, -1.6019, 0.9801); // Notch
// Na het nemen van de absolute waarde moet de tweede BiQuadChain worden toegepast.
// Definieer (twee Low-pass -> vierde orde verkrijgen):
BiQuadChain bqcbr2;
BiQuad bqbr3(1.5515e-4, 3.1030e-4, 1.5515e-4, -1.9645, 0.9651); // Low-pass
BiQuad bqbr4(1.5515e-4, 3.1030e-4, 1.5515e-4, -1.9645, 0.9651); // Low-pass

// BICEPS-LINKS
// Definities voor eerste BiQuadChain (High-pass en Notch)
BiQuadChain bqcbl;
BiQuad bqbl1(0.8006, -1.6012, 0.8006, -1.5610, 0.6414); // High-pass
BiQuad bqbl2(1, -1.6180, 1, -1.6019, 0.9801); // Notch
// Na het nemen van de absolute waarde moet de tweede BiQuadChain worden toegepast.
// Definieer (twee Low-pass -> vierde orde verkrijgen):
BiQuadChain bqcbl2;
BiQuad bqbl3(1.5515e-4, 3.1030e-4, 1.5515e-4, -1.9645, 0.9651); // Low-pass
BiQuad bqbl4(1.5515e-4, 3.1030e-4, 1.5515e-4, -1.9645, 0.9651); // Low-pass

// KUIT
// Definities voor eerste BiQuadChain (High-pass en Notch)
BiQuadChain bqck;
BiQuad bqk1(0.8006, -1.6012, 0.8006, -1.5610, 0.6414); // High-pass
BiQuad bqk2(1, -1.6180, 1, -1.6019, 0.9801); // Notch
// Na het nemen van de absolute waarde moet de tweede BiQuadChain worden toegepast.
// Definieer (twee Low-pass -> vierde orde verkrijgen):
BiQuadChain bqck2;
BiQuad bqk3(1.5515e-4, 3.1030e-4, 1.5515e-4, -1.9645, 0.9651); // Low-pass
BiQuad bqk4(1.5515e-4, 3.1030e-4, 1.5515e-4, -1.9645, 0.9651); // Low-pass

// VARIABELEN VOOR EMG + FILTEREN
double filtered_EMG_biceps_right;
double filtered_EMG_biceps_left;
double filtered_EMG_calf;

double filtered_EMG_biceps_right_1;
double filtered_EMG_biceps_left_1;
double filtered_EMG_calf_1;

double filtered_EMG_biceps_right_abs;
double filtered_EMG_biceps_left_abs;
double filtered_EMG_calf_abs;

double filtered_EMG_biceps_right_total;
double filtered_EMG_biceps_left_total;
double filtered_EMG_calf_total;

// Variabelen voor HIDScope
HIDScope scope(3);

// VARIABELEN VOOR (INITIATIE VAN) EMG KALIBRATIE LOOP
bool calib = false;
static int i_calib = 0;

double mean_EMG_biceps_right;
double mean_EMG_biceps_left;
double mean_EMG_calf;

// VARIABELEN VOOR OPERATION MODE (EMG)
double normalized_EMG_biceps_right;
double normalized_EMG_biceps_left;
double normalized_EMG_calf;

// VARIABELEN VOOR OPERATION MODE (RKI)
double vx; // Gelijk aan variabele die snelheid aangeeft in EMG (in x-richting)
double vy; // Gelijk aan variabele die snelheid aangeeft in EMG (in y-richting)

const double delta_t = 0.002;

double Joint_1_position_x = 0.0;
double Joint_2_position_x = 0.0;

double Joint_1_position_y = 0.0;
double Joint_2_position_y = 0.0;

double Joint_1_position_x_prev = 0.0;
double Joint_2_position_x_prev = 0.0;

double Joint_1_position_y_prev;
double Joint_2_position_y_prev;

double Joint_velocity_x[2][1] = {{0.0}, {0.0}};
double Joint_velocity_y[2][1] = {{0.0}, {0.0}};

double q1_dot_x;
double q2_dot_x;

double q1_dot_y;
double q2_dot_y;

double q1;
double q2;

double Motor_1_position_x = 0.0;
double Motor_2_position_x = 0.0;

double Motor_1_position_y = 0.0;
double Motor_2_position_y = 0.0;

// VARIABELEN VOOR OPERATION MODE (PI-CONTROLLER)

const double Kp = 17.5;
const double Ki = 0.03;

// Voor x-richting
double theta_k_1_x = 0.0;
double theta_k_2_x = 0.0;

double error_integral_1_x = 0.0;
double error_integral_2_x = 0.0;

double u_i_1_x;
double u_i_2_x;

double theta_t_1_x;
double theta_t_2_x;

double error_q1_x;
double error_q2_x;

double abs_theta_t_1_x;
double abs_theta_t_2_x;

// Voor y-richting
double theta_k_1_y = 0.0;
double theta_k_2_y = 0.0;

double error_integral_1_y = 0.0;
double error_integral_2_y = 0.0;

double u_i_1_y;
double u_i_2_y;

double theta_t_1_y;
double theta_t_2_y;

double error_q1_y;
double error_q2_y;

double abs_theta_t_1_y;
double abs_theta_t_2_y;

// VOIDS

// Noodfunctie waarbij alles uitgaat (evt. nog een rood LEDje laten branden).
// Enige optie is resetten, dan wordt het script opnieuw opgestart.
void emergency()
{
    loop_ticker.detach();
    motor1.write(0);
    motor2.write(0);
    pc.printf("Ik ga exploderen!!!\r\n");
}

// Motoren uitzetten
void motors_off()
{
    motor1.write(0);
    motor2.write(0);
    pc.printf("Motoren uit functie\r\n");
}

// Motoren aanzetten
void motors_on()
{
    motor1.write(0.3);
    motor1_dir.write(0);
    motor2.write(0.3);
    motor2_dir.write(1);
    // Door motor 1 een richting van 1 te geven en motor 2 een van 0, draaien
    // beide motoren rechtsom
    pc.printf("Motoren aan functie\r\n");
}

void Inverse_Kinematics()
{
    // Defining joint velocities based on calculations of matlab
    
    Joint_velocity_x[0][0] = (vx*(cos(q1+3.141592653589793/6.0)*-8.5E2-sin(q1)*4.25E2+cos(q1)*cos(q2)*2.25E2+cos(q1)*sin(q2)*6.77E2+cos(q2)*sin(q1)*6.77E2-sin(q1)*sin(q2)*2.25E2+sqrt(3.0)*cos(q1)*4.25E2-sqrt(3.0)*cos(q1)*cos(q2)*4.25E2+sqrt(3.0)*sin(q1)*sin(q2)*4.25E2)*(4.0E1/1.7E1))/(cos(q1)*cos(q1+3.141592653589793/6.0)*4.25E2+sin(q1)*sin(q1+3.141592653589793/6.0)*4.25E2-cos(q1)*sin(q2)*sin(q1+3.141592653589793/6.0)*6.77E2-cos(q2)*sin(q1)*sin(q1+3.141592653589793/6.0)*6.77E2+cos(q1+3.141592653589793/6.0)*sin(q1)*sin(q2)*6.77E2+sin(q1)*sin(q2)*sin(q1+3.141592653589793/6.0)*2.25E2-sqrt(3.0)*cos(q1)*sin(q1+3.141592653589793/6.0)*4.25E2+sqrt(3.0)*cos(q1+3.141592653589793/6.0)*sin(q1)*4.25E2-cos(q1)*cos(q2)*cos(q1+3.141592653589793/6.0)*6.77E2-cos(q1)*cos(q2)*sin(q1+3.141592653589793/6.0)*2.25E2+cos(q1)*cos(q1+3.141592653589793/6.0)*sin(q2)*2.25E2+cos(q2)*cos(q1+3.141592653589793/6.0)*sin(q1)*2.25E2+sqrt(3.0)*cos(q1)*cos(q2)*sin(q1+3.141592653589793/6.0)*4.25E2-sqrt(3.0)*cos(q1)*cos(q1+3.141592653589793/6.0)*sin(q2)*4.25E2-sqrt(3.0)*cos(q2)*cos(q1+3.141592653589793/6.0)*sin(q1)*4.25E2-sqrt(3.0)*sin(q1)*sin(q2)*sin(q1+3.141592653589793/6.0)*4.25E2);
    Joint_velocity_x[1][0] = (vx*(sin(q1)*-4.25E2+cos(q1)*cos(q2)*2.25E2+cos(q1)*sin(q2)*6.77E2+cos(q2)*sin(q1)*6.77E2-sin(q1)*sin(q2)*2.25E2+sqrt(3.0)*cos(q1)*4.25E2-sqrt(3.0)*cos(q1)*cos(q2)*4.25E2+sqrt(3.0)*sin(q1)*sin(q2)*4.25E2)*(-4.0E1/1.7E1))/(cos(q1)*cos(q1+3.141592653589793/6.0)*4.25E2+sin(q1)*sin(q1+3.141592653589793/6.0)*4.25E2-cos(q1)*sin(q2)*sin(q1+3.141592653589793/6.0)*6.77E2-cos(q2)*sin(q1)*sin(q1+3.141592653589793/6.0)*6.77E2+cos(q1+3.141592653589793/6.0)*sin(q1)*sin(q2)*6.77E2+sin(q1)*sin(q2)*sin(q1+3.141592653589793/6.0)*2.25E2-sqrt(3.0)*cos(q1)*sin(q1+3.141592653589793/6.0)*4.25E2+sqrt(3.0)*cos(q1+3.141592653589793/6.0)*sin(q1)*4.25E2-cos(q1)*cos(q2)*cos(q1+3.141592653589793/6.0)*6.77E2-cos(q1)*cos(q2)*sin(q1+3.141592653589793/6.0)*2.25E2+cos(q1)*cos(q1+3.141592653589793/6.0)*sin(q2)*2.25E2+cos(q2)*cos(q1+3.141592653589793/6.0)*sin(q1)*2.25E2+sqrt(3.0)*cos(q1)*cos(q2)*sin(q1+3.141592653589793/6.0)*4.25E2-sqrt(3.0)*cos(q1)*cos(q1+3.141592653589793/6.0)*sin(q2)*4.25E2-sqrt(3.0)*cos(q2)*cos(q1+3.141592653589793/6.0)*sin(q1)*4.25E2-sqrt(3.0)*sin(q1)*sin(q2)*sin(q1+3.141592653589793/6.0)*4.25E2);

    Joint_velocity_y[0][0] = (vy*(cos(q1)*4.25E2-sin(q1+3.141592653589793/6.0)*8.5E2-cos(q1)*cos(q2)*6.77E2+cos(q1)*sin(q2)*2.25E2+cos(q2)*sin(q1)*2.25E2+sin(q1)*sin(q2)*6.77E2+sqrt(3.0)*sin(q1)*4.25E2-sqrt(3.0)*cos(q1)*sin(q2)*4.25E2-sqrt(3.0)*cos(q2)*sin(q1)*4.25E2)*(4.0E1/1.7E1))/(cos(q1)*cos(q1+3.141592653589793/6.0)*4.25E2+sin(q1)*sin(q1+3.141592653589793/6.0)*4.25E2-cos(q1)*sin(q2)*sin(q1+3.141592653589793/6.0)*6.77E2-cos(q2)*sin(q1)*sin(q1+3.141592653589793/6.0)*6.77E2+cos(q1+3.141592653589793/6.0)*sin(q1)*sin(q2)*6.77E2+sin(q1)*sin(q2)*sin(q1+3.141592653589793/6.0)*2.25E2-sqrt(3.0)*cos(q1)*sin(q1+3.141592653589793/6.0)*4.25E2+sqrt(3.0)*cos(q1+3.141592653589793/6.0)*sin(q1)*4.25E2-cos(q1)*cos(q2)*cos(q1+3.141592653589793/6.0)*6.77E2-cos(q1)*cos(q2)*sin(q1+3.141592653589793/6.0)*2.25E2+cos(q1)*cos(q1+3.141592653589793/6.0)*sin(q2)*2.25E2+cos(q2)*cos(q1+3.141592653589793/6.0)*sin(q1)*2.25E2+sqrt(3.0)*cos(q1)*cos(q2)*sin(q1+3.141592653589793/6.0)*4.25E2-sqrt(3.0)*cos(q1)*cos(q1+3.141592653589793/6.0)*sin(q2)*4.25E2-sqrt(3.0)*cos(q2)*cos(q1+3.141592653589793/6.0)*sin(q1)*4.25E2-sqrt(3.0)*sin(q1)*sin(q2)*sin(q1+3.141592653589793/6.0)*4.25E2);
    Joint_velocity_y[1][0] = (vy*(cos(q1)*4.25E2-cos(q1)*cos(q2)*6.77E2+cos(q1)*sin(q2)*2.25E2+cos(q2)*sin(q1)*2.25E2+sin(q1)*sin(q2)*6.77E2+sqrt(3.0)*sin(q1)*4.25E2-sqrt(3.0)*cos(q1)*sin(q2)*4.25E2-sqrt(3.0)*cos(q2)*sin(q1)*4.25E2)*(-4.0E1/1.7E1))/(cos(q1)*cos(q1+3.141592653589793/6.0)*4.25E2+sin(q1)*sin(q1+3.141592653589793/6.0)*4.25E2-cos(q1)*sin(q2)*sin(q1+3.141592653589793/6.0)*6.77E2-cos(q2)*sin(q1)*sin(q1+3.141592653589793/6.0)*6.77E2+cos(q1+3.141592653589793/6.0)*sin(q1)*sin(q2)*6.77E2+sin(q1)*sin(q2)*sin(q1+3.141592653589793/6.0)*2.25E2-sqrt(3.0)*cos(q1)*sin(q1+3.141592653589793/6.0)*4.25E2+sqrt(3.0)*cos(q1+3.141592653589793/6.0)*sin(q1)*4.25E2-cos(q1)*cos(q2)*cos(q1+3.141592653589793/6.0)*6.77E2-cos(q1)*cos(q2)*sin(q1+3.141592653589793/6.0)*2.25E2+cos(q1)*cos(q1+3.141592653589793/6.0)*sin(q2)*2.25E2+cos(q2)*cos(q1+3.141592653589793/6.0)*sin(q1)*2.25E2+sqrt(3.0)*cos(q1)*cos(q2)*sin(q1+3.141592653589793/6.0)*4.25E2-sqrt(3.0)*cos(q1)*cos(q1+3.141592653589793/6.0)*sin(q2)*4.25E2-sqrt(3.0)*cos(q2)*cos(q1+3.141592653589793/6.0)*sin(q1)*4.25E2-sqrt(3.0)*sin(q1)*sin(q2)*sin(q1+3.141592653589793/6.0)*4.25E2);

    // Integratie
    Joint_1_position_x = Joint_1_position_x_prev + Joint_velocity_x[0][0]*delta_t;
    Joint_2_position_x = Joint_2_position_x_prev + Joint_velocity_x[1][0]*delta_t;

    Joint_1_position_y = Joint_1_position_y_prev + Joint_velocity_y[0][0]*delta_t;
    Joint_2_position_y = Joint_2_position_y_prev + Joint_velocity_y[1][0]*delta_t;

    Joint_1_position_x_prev = Joint_1_position_x;
    Joint_2_position_x_prev = Joint_2_position_x;

    Joint_1_position_y_prev = Joint_1_position_y;
    Joint_2_position_y_prev = Joint_2_position_y;

    Motor_1_position_x = Joint_1_position_x;
    Motor_2_position_x = Joint_1_position_x + Joint_2_position_x;

    Motor_1_position_y = Joint_1_position_y;
    Motor_2_position_y = Joint_1_position_y + Joint_2_position_y;
}

// PI-CONTROLLER X-RICHTING
void PI_controller_x()
{
// Proportional part:
    theta_k_1_x= Kp * error_q1_x;
    theta_k_2_x= Kp * error_q2_x;

// Integral part
    error_integral_1_x = error_integral_1_x + error_q1_x *delta_t;
    error_integral_2_x = error_integral_2_x + error_q2_x *delta_t;
    u_i_1_x= Ki * error_integral_1_x;
    u_i_2_x= Ki * error_integral_2_x;

// sum all parts and return it
    theta_t_1_x = theta_k_1_x + u_i_1_x;
    theta_t_2_x = theta_k_2_x + u_i_2_x;
}

// PI-CONTROLLER Y-RICHTING
void PI_controller_y()
{
// Proportional part:
    theta_k_1_y= Kp * error_q1_y;
    theta_k_2_y= Kp * error_q2_y;

// Integral part
    error_integral_1_y = error_integral_1_y + error_q1_y *delta_t;
    error_integral_2_y = error_integral_2_y + error_q2_y *delta_t;
    u_i_1_y= Ki * error_integral_1_y;
    u_i_2_y= Ki * error_integral_2_y;

// sum all parts and return it
    theta_t_1_y = theta_k_1_y + u_i_1_y;
    theta_t_2_y = theta_k_2_y + u_i_2_y;
}

void Define_motor_dir_x()
{
    if (theta_t_1_x >= 0 && theta_t_2_x >= 0) {
        motor1_dir.write(0);
        motor2_dir.write(1);
    }
    if (theta_t_1_x < 0 && theta_t_2_x >= 0) {
        motor1_dir.write(1);
        motor1_dir.write(1);
    }
    if (theta_t_1_x >= 0 && theta_t_2_x < 0) {
        motor1_dir.write(0);
        motor2_dir.write(0);
    } else {
        motor1_dir.write(1);
        motor2_dir.write(0);
    }
}

void Define_motor_dir_y()
{
    if (theta_t_1_y >= 0 && theta_t_2_y >= 0) {
        motor1_dir.write(0);
        motor2_dir.write(1);
    }
    if (theta_t_1_y < 0 && theta_t_2_y >= 0) {
        motor1_dir.write(1);
        motor1_dir.write(1);
    }
    if (theta_t_1_y >= 0 && theta_t_2_y < 0) {
        motor1_dir.write(0);
        motor2_dir.write(0);
    } else {
        motor1_dir.write(1);
        motor2_dir.write(0);
    }
}
// Finite state machine programming (calibration servo motor?)
void ProcessStateMachine(void)
{
    // Berekenen van de motorhoeken (in radialen)
    pulses_M1 = Encoder1.getPulses();
    pulses_M2 = Encoder2.getPulses();
    counts1 = pulses_M1*2;
    counts2 = pulses_M2*2;
    theta_h_1_rad = conversion_factor*counts1;
    theta_h_2_rad = conversion_factor*counts2;

    // Calculating joint angles based on motor angles (current encoder values)
    q1 = theta_h_1_rad;                       // Relative angle joint 1 (rad)
    q2 = theta_h_2_rad - theta_h_1_rad;       // Relative angle joint 2 (rad)

    // Eerste deel van de filters (High-pass + Notch) over het ruwe EMG signaal
    // doen. Het ruwe signaal wordt gelezen binnen een ticker en wordt daardoor 'gesampled'
    filtered_EMG_biceps_right_1=bqbr1.step(EMG_biceps_right_raw.read());
    filtered_EMG_biceps_left_1=bqcbl.step(EMG_biceps_left_raw.read());
    filtered_EMG_calf_1=bqck.step(EMG_calf_raw.read());

    // Vervolgens wordt de absolute waarde hiervan genomen
    filtered_EMG_biceps_right_abs=abs(filtered_EMG_biceps_right_1);
    filtered_EMG_biceps_left_abs=abs(filtered_EMG_biceps_left_1);
    filtered_EMG_calf_abs=abs(filtered_EMG_calf_1);

    // Tenslotte wordt het tweede deel van de filters (twee low-pass, voor 4e orde filter)
    // over het signaal gedaan
    filtered_EMG_biceps_right=bqcbr2.step(filtered_EMG_biceps_right_abs);
    filtered_EMG_biceps_left=bqcbl2.step(filtered_EMG_biceps_left_abs);
    filtered_EMG_calf=bqck2.step(filtered_EMG_calf_abs);

    // De gefilterde EMG-signalen kunnen tevens visueel worden weergegeven in de HIDScope
    scope.set(0, normalized_EMG_biceps_right);
    scope.set(1, normalized_EMG_biceps_left);
    scope.set(2, normalized_EMG_calf);
    scope.send();

    // Tijdens de kalibratie moet vervolgens een maximale spierspanning worden bepaald, die
    // later kan worden gebruikt voor een normalisatie. De spieren worden hiertoe gedurende
    // 5 seconden maximaal aangespannen. De EMG waarden worden bij elkaar opgeteld,
    // waarna het gemiddelde wordt bepaald.
    if (calib) {
        if (i_calib == 0) {
            filtered_EMG_biceps_right_total=0;
            filtered_EMG_biceps_left_total=0;
            filtered_EMG_calf_total=0;
        }
        if (i_calib <= 2500) {
            filtered_EMG_biceps_right_total+=filtered_EMG_biceps_right;
            filtered_EMG_biceps_left_total+=filtered_EMG_biceps_left;
            filtered_EMG_calf_total+=filtered_EMG_calf;
            i_calib++;
        }
        if (i_calib > 2500) {
            mean_EMG_biceps_right=filtered_EMG_biceps_right_total/2500.0;
            mean_EMG_biceps_left=filtered_EMG_biceps_left_total/2500.0;
            mean_EMG_calf=filtered_EMG_calf_total/2500.0;
            pc.printf("Ontspan spieren\r\n");
            pc.printf("Rechterbiceps_max = %f, Linkerbiceps_max = %f, Kuit_max = %f\r\n", mean_EMG_biceps_right, mean_EMG_biceps_left, mean_EMG_calf);
            calib = false;
        }
    }

    // Genormaliseerde EMG's berekenen
    normalized_EMG_biceps_right=filtered_EMG_biceps_right/mean_EMG_biceps_right;
    normalized_EMG_biceps_left=filtered_EMG_biceps_left/mean_EMG_biceps_left;
    normalized_EMG_calf=filtered_EMG_calf/mean_EMG_calf;

    // Finite state machine
    switch (currentState) {
        case Motors_off:

            if (stateChanged) {
                motors_off(); // functie waarbij motoren uitgaan
                stateChanged = false;
                pc.printf("Motors off state\r\n");
            }
            if  (Emergency_button_pressed.read() == false) { // Normaal waarde 1 bij indrukken, nu nul -> false
                emergency();
            }
            if  (Power_button_pressed.read() == false) { // Normaal waarde 1 bij indrukken, nu nul -> false
                currentState = Calib_motor;
                stateChanged = true;
                pc.printf("Moving to Calib_motor state\r\n");
            }
            break;

        case Calib_motor:

            if (stateChanged) {
                pc.printf("Zet motoren handmatig in home positie\r\n");
                stateChanged = false;
            }

            if  (Emergency_button_pressed.read() == false) {
                emergency();
            }
            if (Motor_calib_button_pressed.read() == false) {
                theta_h_1_rad = 0;
                theta_h_2_rad = 0;
                pc.printf("Huidige hoek in radialen motor 1:%f en motor 2: %f (moet 0 zijn) \r\n", theta_h_1_rad, theta_h_2_rad);
                currentState = Calib_EMG;
                stateChanged = true;
                pc.printf("Moving to Calib_EMG state\r\n");
            }
            break;

        case Calib_EMG:

            if (stateChanged) {
                i_calib = 0;
                calib = true;
                pc.printf("Span spieren aan\r\n");
                stateChanged = false;
            }

            if  (Emergency_button_pressed.read() == false) {
                emergency();
            }

            if (i_calib > 2500) {
                calib = false;
                currentState = Homing;
                stateChanged = true;
                pc.printf("Moving to Homing state\r\n");
            }
            break;

        case Homing: 

            if (stateChanged) {
                // Ervoor zorgen dat de motoren zo bewegen dat de robotarm
                // (inclusief de end-effector) in de juiste home positie wordt gezet
                stateChanged = false;
            }
            if  (Emergency_button_pressed.read() == false) {
                emergency();
            }

            if (theta_h_1_rad != 0.0) {
                if (theta_h_1_rad < 0) {
                    motor1.write(0.3);
                    motor1_dir.write(0);
                } else {
                    motor1.write(0.3);
                    motor1_dir.write(1);
                }
            }
            if (theta_h_1_rad == 0.0) {
                motor1.write(0);
            }
            if (theta_h_2_rad != 0.0) {
                if (theta_h_2_rad < 0) {
                    motor2.write(0.3);
                    motor2_dir.write(1);
                } else {
                    motor2.write(0.3);
                    motor2_dir.write(0);
                }
            }
            if (theta_h_2_rad == 0.0) {
                motor2.write(0);
            }

            if (theta_h_1_rad == 0.0 && theta_h_2_rad == 0.0)
                // Veranderen wanneer encoders werken en motor in elkaar zit
            {
                currentState = Operation_mode;
                stateChanged = true;
                pc.printf("Moving to operation mode \r\n");
            }

            break;

        case Operation_mode: // Overgaan tot emergency wanneer referentie niet
            // overeenkomt met werkelijkheid

            // pc.printf("normalized_EMG_biceps_right= %f, mean_EMG_biceps_right = %f, filtered_EMG_biceps_right = %f\r\n", normalized_EMG_biceps_right, mean_EMG_biceps_right, filtered_EMG_biceps_right);
            if (stateChanged) {
                motors_off();
                Joint_1_position_x = 0;
                Joint_2_position_x = 0;
                Joint_1_position_y = 0;
                Joint_2_position_y = 0;
                Joint_1_position_x_prev = Joint_1_position_x;
                Joint_2_position_x_prev = Joint_2_position_x;
                Joint_1_position_y_prev = Joint_1_position_y;
                Joint_2_position_y_prev = Joint_2_position_y;
                Joint_velocity_x[0][0] = 0;
                Joint_velocity_x[1][0] = 0;
                Joint_velocity_y[0][0] = 0;
                Joint_velocity_y[1][0] = 0;
                Motor_1_position_x = 0;
                Motor_2_position_x = 0;
                Motor_1_position_y = 0;
                Motor_2_position_y = 0;
                theta_k_1_x = 0.0;
                theta_k_2_x = 0.0;
                error_integral_1_x = 0.0;
                error_integral_2_x = 0.0;
                theta_k_1_y = 0.0;
                theta_k_2_y = 0.0;
                error_integral_1_y = 0.0;
                error_integral_2_y = 0.0;
                stateChanged = false;
            }
            // Hier moet een functie worden aangeroepen die ervoor zorgt dat
            // aan de hand van EMG-signalen de motoren kunnen worden aangestuurd,
            // zodat de robotarm kan bewegen

            // if (Power_button_pressed.read() == false) { // Normaal waarde 1 bij indrukken, nu nul -> false
            // motors_off();
            // currentState = Motors_off;
            // stateChanged = true;
            // pc.printf("Terug naar de state Motors_off\r\n");
            // }
            if (Emergency_button_pressed.read() == false) {
                emergency();
            }
            if (Motor_calib_button_pressed.read() == false) { // Is nu voor de homing
                motors_off();
                currentState = Homing;
                stateChanged = true;
                pc.printf("Terug naar de state Homing\r\n");
            }
            if (normalized_EMG_biceps_right >= 0.3) {

                if (normalized_EMG_calf < 0.3) {
                    vx = 0.0;
                    vy = 0.05;
                }
                if (normalized_EMG_calf >= 0.3) {
                    vx = 0.0;
                    vy = -0.05;
                }
                Inverse_Kinematics();
                error_q1_y = Motor_1_position_y - theta_h_1_rad;
                error_q2_y = Motor_2_position_y - theta_h_2_rad;
                PI_controller_y();

                abs_theta_t_1_y = abs(theta_t_1_y);
                abs_theta_t_2_y = abs(theta_t_2_y);

                motor1.write(abs_theta_t_1_y);
                motor2.write(abs_theta_t_2_y);
                Define_motor_dir_y();

            } else if (normalized_EMG_biceps_left >= 0.3) {
                if (normalized_EMG_calf < 0.3) {
                    vx = 0.05;
                    vy = 0.0;
                }
                if (normalized_EMG_calf >= 0.3) {
                    vx = -0.05;
                    vy = 0.0;
                }
                Inverse_Kinematics();
                error_q1_x = Motor_1_position_x - theta_h_1_rad;
                error_q2_x = Motor_2_position_x - theta_h_2_rad;
                PI_controller_x();

                abs_theta_t_1_x = abs(theta_t_1_x);
                abs_theta_t_2_x = abs(theta_t_2_x);

                motor1.write(abs_theta_t_1_x);
                motor2.write(abs_theta_t_2_x);
                Define_motor_dir_x();

            } else {
                motor1.write(0);
                motor2.write(0);
            }

            break;

        default:
            // Zelfde functie als die eerder is toegepast om motoren uit te schakelen -> safety!
            motors_off();
            pc.printf("Unknown or uninplemented state reached!\r\n");

    }
}

int main(void)
{
    pc.printf("Opstarten\r\n");

    // Chain voor rechter biceps
    bqcbr.add(&bqbr1).add(&bqbr2);
    bqcbr2.add(&bqbr3).add(&bqbr4);
    // Chain voor linker biceps
    bqcbl.add(&bqbl1).add(&bqbl2);
    bqcbl2.add(&bqbl3).add(&bqbl4);
    // Chain voor kuit
    bqck.add(&bqk1).add(&bqk2);
    bqck2.add(&bqk3).add(&bqk4);

    loop_ticker.attach(&ProcessStateMachine, 0.002f);

    while(true) {
        // wait(0.2);
        /* do nothing */
    }
}