PID.h

00001 // by MaEtUgR
00002 
00003 #ifndef PID_H
00004 #define PID_H
00005 
00006 #include "mbed.h"
00007 
00008 #define BUFFERSIZE 5
00009 
00010 class PID {
00011     public:
00012         PID(float P, float I, float D, float Integral_Max);
00013         void compute(float SetPoint, float ProcessValue);
00014         void setIntegrate(bool Integrate);
00015         void setPID(float P, float I, float D);
00016         
00017         float Value;
00018     
00019     private:
00020         float P, I, D; // PID Values and limits
00021         
00022         Timer dtTimer;  // Timer to measure time between every compute
00023         float LastTime; // Time when last loop was
00024         
00025         float Integral; // the sum of all errors (constaind so it doesn't get infinite)
00026         float Integral_Max; // maximum that the sum of all errors can get (not important: last error not counted)
00027         bool Integrate; // if the integral is used / the controller is in use
00028         
00029         float PreviousError; // the Error of the last computation to get derivative
00030         float RollBuffer[BUFFERSIZE];  // Rollingbufferarray for derivative to filter noise
00031         int RollBufferIndex;
00032 };
00033 
00034 #endif