PIDController.h

/*----------------------------------------------------------------------------*/
/* Copyright (c) FIRST 2008. All Rights Reserved.                                                         */
/* Open Source Software - may be modified and shared by FRC teams. The code   */
/* must be accompanied by the FIRST BSD license file in $(WIND_BASE)/WPILib.  */
/*----------------------------------------------------------------------------*/

#ifndef PIDCONTROLLER_H_
#define PIDCONTROLLER_H_

#include "Base.h"
#include "semLib.h"

class PIDOutput;
class PIDSource;
class Notifier;

class PIDController
{
public:
        PIDController(float p, float i, float d,
                                        PIDSource *source, PIDOutput *output,
                                        float period = 0.05);
        virtual ~PIDController();
        virtual float Get();
        virtual void SetContinuous(bool continuous = true);
        virtual void SetInputRange(float minimumInput, float maximumInput);
        virtual void SetOutputRange(float mimimumOutput, float maximumOutput);
        virtual void SetPID(float p, float i, float d);
        virtual float GetP();
        virtual float GetI();
        virtual float GetD();
        
        virtual void SetSetpoint(float setpoint);
        virtual float GetSetpoint();

        virtual float GetError();
        
        virtual void SetTolerance(float percent);
        virtual bool OnTarget();
        
        virtual void Enable();
        virtual void Disable();
        virtual bool IsEnabled();
        
        virtual void Reset();

private:
        float m_P;                      // factor for "proportional" control
        float m_I;                      // factor for "integral" control
        float m_D;                      // factor for "derivative" control
        float m_maximumOutput;  // |maximum output|
        float m_minimumOutput;  // |minimum output|
        float m_maximumInput;           // maximum input - limit setpoint to this
        float m_minimumInput;           // minimum input - limit setpoint to this
        bool m_continuous;      // do the endpoints wrap around? eg. Absolute encoder
        bool m_enabled;                         //is the pid controller enabled
        float m_prevError;      // the prior sensor input (used to compute velocity)
        double m_totalError; //the sum of the errors for use in the integral calc
        float m_tolerance;      //the percetage error that is considered on target
        float m_setpoint;
        float m_error;
        float m_result;
        float m_period;
        
        SEM_ID m_semaphore;
        
        PIDSource *m_pidInput;
        PIDOutput *m_pidOutput;
        Notifier *m_controlLoop;

        static void CallCalculate(void *controller);
        void Calculate();
        DISALLOW_COPY_AND_ASSIGN(PIDController);
};

#endif