encoder.h

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#ifndef ENCODER_H
#define ENCODER_H
 
#include "QEI.h"
#include "mbed.h"
#include <chrono>
 
#define GEAR_RATIO 18.75
#define DIAMETER 0.08
#define WHEEL_DISTANCE 0.212
#define COUNTS_PER_REV 256
#define POLLING_PERIOD 10ms
 
#ifndef M_PI
#define M_PI 3.14159265358979323846264338327950288
#endif
 
class Encoder : public QEI {
  private:
    volatile int m_start_pulse;
 
    volatile int m_end_pulse;
 
    volatile int m_pulse_width;
 
    volatile int m_pulse_counter;
 
    volatile double m_pulse_per_sec;
 
    volatile double m_velocity;
 
    Timer m_t;
 
    Timeout m_to;
 
  public:
    Encoder(PinName A, PinName B);
 
    static constexpr double CIRCUMFERENCE = DIAMETER * M_PI;
 
    static constexpr double FULL_ROTATION_SIDE_PIVOT = 2.0 * M_PI * WHEEL_DISTANCE;
 
    static constexpr double FULL_ROTATION_CENTER_PIVOT = M_PI * WHEEL_DISTANCE;
 
    void start();
 
    int getCounter() const;
 
    void resetCounter();
 
    double getVelocity() const;
 
    double getDistance() const;
 
    double getPPS() const;
 
    static double getAverageAngular(const Encoder &right_encoder, const Encoder &left_encoder);
 
    static double getAverageVelocity(const Encoder &right_encoder, const Encoder &left_encoder);
 
    static double getAverageDistance(const Encoder &right_encoder, const Encoder &left_encoder);
 
  private:
    void m_calculateSpeed(const double &time_elapsed);
 
    void m_stop();
};
 
#endif