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integerPID alternative class

This commit is contained in:
Josh Stewart 2016-04-09 09:19:32 +10:00
parent fb095d8cfc
commit 61a2c22ee2
2 changed files with 267 additions and 1 deletions
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191
PID_v1.cpp
View File

@ -11,7 +11,8 @@
#include "WProgram.h"
#endif
#include <PID_v1.h>
#include "PID_v1.h"
/*Constructor (...)*********************************************************
* The parameters specified here are those for for which we can't set up
@ -193,3 +194,191 @@ double PID::GetKd(){ return dispKd;}
int PID::GetMode(){ return inAuto ? AUTOMATIC : MANUAL;}
int PID::GetDirection(){ return controllerDirection;}
/*Constructor (...)*********************************************************
* The parameters specified here are those for for which we can't set up
* reliable defaults, so we need to have the user set them.
***************************************************************************/
integerPID::integerPID(long* Input, long* Output, long* Setpoint,
byte Kp, byte Ki, byte Kd, byte ControllerDirection)
{
myOutput = Output;
myInput = Input;
mySetpoint = Setpoint;
inAuto = false;
integerPID::SetOutputLimits(0, 255); //default output limit corresponds to
//the arduino pwm limits
//SampleTime = 100; //default Controller Sample Time is 0.1 seconds
integerPID::SetControllerDirection(ControllerDirection);
integerPID::SetTunings(Kp, Ki, Kd);
//lastTime = millis()-SampleTime;
}
/* Compute() **********************************************************************
* This, as they say, is where the magic happens. this function should be called
* every time "void loop()" executes. the function will decide for itself whether a new
* pid Output needs to be computed. returns true when the output is computed,
* false when nothing has been done.
**********************************************************************************/
bool integerPID::Compute()
{
if(!inAuto) return false;
unsigned long now = millis();
SampleTime = (now - lastTime);
//if(timeChange>=SampleTime)
{
/*Compute all the working error variables*/
long input = *myInput;
long error = *mySetpoint - input;
ITerm+= (ki * error)/100;
//ITerm+= divs100(ki * error);
if(ITerm > outMax) ITerm= outMax;
else if(ITerm < outMin) ITerm= outMin;
long dInput = (input - lastInput);
/*Compute PID Output*/
long output = (kp * error)/100 + ITerm- (kd * dInput)/100;
//long output = divs100(kp * error) + ITerm- divs100(kd * dInput);
if(output > outMax) output = outMax;
else if(output < outMin) output = outMin;
*myOutput = output;
/*Remember some variables for next time*/
lastInput = input;
//lastTime = now;
return true;
}
//else return false;
}
/* SetTunings(...)*************************************************************
* This function allows the controller's dynamic performance to be adjusted.
* it's called automatically from the constructor, but tunings can also
* be adjusted on the fly during normal operation
******************************************************************************/
void integerPID::SetTunings(byte Kp, byte Ki, byte Kd)
{
if (Kp<0 || Ki<0 || Kd<0) return;
dispKp = Kp; dispKi = Ki; dispKd = Kd;
/*
double SampleTimeInSec = ((double)SampleTime)/1000;
kp = Kp;
ki = Ki * SampleTimeInSec;
kd = Kd / SampleTimeInSec;
*/
long InverseSampleTimeInSec = 100000 / SampleTime;
kp = Kp;
ki = (Ki * 100) / InverseSampleTimeInSec;
kd = (Kd * InverseSampleTimeInSec) / 100;
if(controllerDirection ==REVERSE)
{
kp = (0 - kp);
ki = (0 - ki);
kd = (0 - kd);
}
}
/* SetSampleTime(...) *********************************************************
* sets the period, in Milliseconds, at which the calculation is performed
******************************************************************************/
void integerPID::SetSampleTime(int NewSampleTime)
{
if (NewSampleTime > 0)
{
unsigned long ratioX1000 = (unsigned long)(NewSampleTime * 1000) / (unsigned long)SampleTime;
ki = (ki * ratioX1000) / 1000;
//kd /= ratio;
kd = (kd * 1000) / ratioX1000;
SampleTime = (unsigned long)NewSampleTime;
}
}
/* SetOutputLimits(...)****************************************************
* This function will be used far more often than SetInputLimits. while
* the input to the controller will generally be in the 0-1023 range (which is
* the default already,) the output will be a little different. maybe they'll
* be doing a time window and will need 0-8000 or something. or maybe they'll
* want to clamp it from 0-125. who knows. at any rate, that can all be done
* here.
**************************************************************************/
void integerPID::SetOutputLimits(long Min, long Max)
{
if(Min >= Max) return;
outMin = Min;
outMax = Max;
if(inAuto)
{
if(*myOutput > outMax) *myOutput = outMax;
else if(*myOutput < outMin) *myOutput = outMin;
if(ITerm > outMax) ITerm= outMax;
else if(ITerm < outMin) ITerm= outMin;
}
}
/* SetMode(...)****************************************************************
* Allows the controller Mode to be set to manual (0) or Automatic (non-zero)
* when the transition from manual to auto occurs, the controller is
* automatically initialized
******************************************************************************/
void integerPID::SetMode(int Mode)
{
bool newAuto = (Mode == AUTOMATIC);
if(newAuto == !inAuto)
{ /*we just went from manual to auto*/
integerPID::Initialize();
}
inAuto = newAuto;
}
/* Initialize()****************************************************************
* does all the things that need to happen to ensure a bumpless transfer
* from manual to automatic mode.
******************************************************************************/
void integerPID::Initialize()
{
ITerm = *myOutput;
lastInput = *myInput;
if(ITerm > outMax) ITerm = outMax;
else if(ITerm < outMin) ITerm = outMin;
}
/* SetControllerDirection(...)*************************************************
* The PID will either be connected to a DIRECT acting process (+Output leads
* to +Input) or a REVERSE acting process(+Output leads to -Input.) we need to
* know which one, because otherwise we may increase the output when we should
* be decreasing. This is called from the constructor.
******************************************************************************/
void integerPID::SetControllerDirection(byte Direction)
{
if(inAuto && Direction !=controllerDirection)
{
kp = (0 - kp);
ki = (0 - ki);
kd = (0 - kd);
}
controllerDirection = Direction;
}
/* Status Funcions*************************************************************
* Just because you set the Kp=-1 doesn't mean it actually happened. these
* functions query the internal state of the PID. they're here for display
* purposes. this are the functions the PID Front-end uses for example
******************************************************************************/
byte integerPID::GetKp(){ return dispKp; }
byte integerPID::GetKi(){ return dispKi;}
byte integerPID::GetKd(){ return dispKd;}
int integerPID::GetMode(){ return inAuto ? AUTOMATIC : MANUAL;}
int integerPID::GetDirection(){ return controllerDirection;}

77
PID_v1.h
View File

@ -76,5 +76,82 @@ class PID
double outMin, outMax;
bool inAuto;
};
class integerPID
{
public:
//Constants used in some of the functions below
#define AUTOMATIC 1
#define MANUAL 0
#define DIRECT 0
#define REVERSE 1
//commonly used functions **************************************************************************
integerPID(long*, long*, long*, // * constructor. links the PID to the Input, Output, and
byte, byte, byte, byte); // Setpoint. Initial tuning parameters are also set here
void SetMode(int Mode); // * sets PID to either Manual (0) or Auto (non-0)
bool Compute(); // * performs the PID calculation. it should be
// called every time loop() cycles. ON/OFF and
// calculation frequency can be set using SetMode
// SetSampleTime respectively
void SetOutputLimits(long, long); //clamps the output to a specific range. 0-255 by default, but
//it's likely the user will want to change this depending on
//the application
//available but not commonly used functions ********************************************************
void SetTunings(byte, byte, // * While most users will set the tunings once in the
byte); // constructor, this function gives the user the option
// of changing tunings during runtime for Adaptive control
void SetControllerDirection(byte); // * Sets the Direction, or "Action" of the controller. DIRECT
// means the output will increase when error is positive. REVERSE
// means the opposite. it's very unlikely that this will be needed
// once it is set in the constructor.
void SetSampleTime(int); // * sets the frequency, in Milliseconds, with which
// the PID calculation is performed. default is 100
//Display functions ****************************************************************
byte GetKp(); // These functions query the pid for interal values.
byte GetKi(); // they were created mainly for the pid front-end,
byte GetKd(); // where it's important to know what is actually
int GetMode(); // inside the PID.
int GetDirection(); //
private:
void Initialize();
byte dispKp; // * we'll hold on to the tuning parameters in user-entered
byte dispKi; // format for display purposes
byte dispKd; //
byte kp; // * (P)roportional Tuning Parameter
byte ki; // * (I)ntegral Tuning Parameter
byte kd; // * (D)erivative Tuning Parameter
int controllerDirection;
long *myInput; // * Pointers to the Input, Output, and Setpoint variables
long *myOutput; // This creates a hard link between the variables and the
long *mySetpoint; // PID, freeing the user from having to constantly tell us
// what these values are. with pointers we'll just know.
unsigned long lastTime;
long ITerm, lastInput;
unsigned long SampleTime;
long outMin, outMax;
bool inAuto;
};
#endif