I began porting the Arduino Autotune Library and I was very successfull so far. My hopefully last error is in line 126 of my autotune.ino
autotune.ino:
// This #include statement was automatically added by the Particle IDE.
#include "PID_AutoTune_v0.h"
// This #include statement was automatically added by the Particle IDE.
#include "pid/pid.h"
byte ATuneModeRemember=2;
double input=80, output=50, setpoint=180;
double kp=2,ki=0.5,kd=2;
double kpmodel=1.5, taup=100, theta[50];
double outputStart=5;
double aTuneStep=50, aTuneNoise=1, aTuneStartValue=100;
unsigned int aTuneLookBack=20;
boolean tuning = false;
unsigned long modelTime, serialTime;
PID myPID(&input, &output, &setpoint,kp,ki,kd, PID::DIRECT);
PID_ATune aTune(&input, &output);
//set to false to connect to the real world
boolean useSimulation = true;
void setup()
{
if(useSimulation)
{
for(byte i=0;i<50;i++)
{
theta[i]=outputStart;
}
modelTime = 0;
}
//Setup the pid
myPID.SetMode(PID::AUTOMATIC);
if(tuning)
{
tuning=false;
changeAutoTune();
tuning=true;
}
serialTime = 0;
Serial.begin(9600);
}
void loop()
{
unsigned long now = millis();
if(!useSimulation)
{ //pull the input in from the real world
input = analogRead(0);
}
if(tuning)
{
byte val = (aTune.Runtime());
if (val!=0)
{
tuning = false;
}
if(!tuning)
{ //we're done, set the tuning parameters
kp = aTune.GetKp();
ki = aTune.GetKi();
kd = aTune.GetKd();
myPID.SetTunings(kp,ki,kd);
AutoTuneHelper(false);
}
}
else myPID.Compute();
if(useSimulation)
{
theta[30]=output;
if(now>=modelTime)
{
modelTime +=100;
DoModel();
}
}
else
{
analogWrite(0,output);
}
//send-receive with processing if it's time
if(millis()>serialTime)
{
SerialReceive();
SerialSend();
serialTime+=500;
}
}
void changeAutoTune()
{
if(!tuning)
{
//Set the output to the desired starting frequency.
output=aTuneStartValue;
aTune.SetNoiseBand(aTuneNoise);
aTune.SetOutputStep(aTuneStep);
aTune.SetLookbackSec((int)aTuneLookBack);
AutoTuneHelper(true);
tuning = true;
}
else
{ //cancel autotune
aTune.Cancel();
tuning = false;
AutoTuneHelper(false);
}
}
void AutoTuneHelper(boolean start)
{
if(start)
ATuneModeRemember = myPID.GetMode();
else
myPID.SetMode(ATuneModeRemember);
}
void SerialSend()
{
Serial.print("setpoint: ");Serial.print(setpoint); Serial.print(" ");
Serial.print("input: ");Serial.print(input); Serial.print(" ");
Serial.print("output: ");Serial.print(output); Serial.print(" ");
if(tuning){
Serial.println("tuning mode");
} else {
Serial.print("kp: ");Serial.print(myPID.GetKp());Serial.print(" ");
Serial.print("ki: ");Serial.print(myPID.GetKi());Serial.print(" ");
Serial.print("kd: ");Serial.print(myPID.GetKd());Serial.println();
}
}
void SerialReceive()
{
if(Serial.available())
{
char b = Serial.read();
Serial.flush();
if((b=='1' && !tuning) || (b!='1' && tuning))changeAutoTune();
}
}
void DoModel()
{
//cycle the dead time
for(byte i=0;i<49;i++)
{
theta[i] = theta[i+1];
}
//compute the input
input = (kpmodel / taup) *(theta[0]-outputStart) + input*(1-1/taup) + ((float)random(-10,10))/100;
}
PID_AutoTune_v0.cpp
#include <PID_AutoTune_v0.h>
#include "application.h"
PID_ATune::PID_ATune(double* Input, double* Output)
{
input = Input;
output = Output;
controlType =0 ; //default to PI
noiseBand = 0.5;
running = false;
oStep = 30;
SetLookbackSec(10);
lastTime = millis();
}
void PID_ATune::Cancel()
{
running = false;
}
int PID_ATune::Runtime()
{
justevaled=false;
if(peakCount>9 && running)
{
running = false;
FinishUp();
return 1;
}
unsigned long now = millis();
if((now-lastTime)<sampleTime) return false;
lastTime = now;
double refVal = *input;
justevaled=true;
if(!running)
{ //initialize working variables the first time around
peakType = 0;
peakCount=0;
justchanged=false;
absMax=refVal;
absMin=refVal;
setpoint = refVal;
running = true;
outputStart = *output;
*output = outputStart+oStep;
}
else
{
if(refVal>absMax)absMax=refVal;
if(refVal<absMin)absMin=refVal;
}
//oscillate the output base on the input's relation to the setpoint
if(refVal>setpoint+noiseBand) *output = outputStart-oStep;
else if (refVal<setpoint-noiseBand) *output = outputStart+oStep;
//bool isMax=true, isMin=true;
isMax=true;isMin=true;
//id peaks
for(int i=nLookBack-1;i>=0;i--)
{
double val = lastInputs[i];
if(isMax) isMax = refVal>val;
if(isMin) isMin = refVal<val;
lastInputs[i+1] = lastInputs[i];
}
lastInputs[0] = refVal;
if(nLookBack<9)
{ //we don't want to trust the maxes or mins until the inputs array has been filled
return 0;
}
if(isMax)
{
if(peakType==0)peakType=1;
if(peakType==-1)
{
peakType = 1;
justchanged=true;
peak2 = peak1;
}
peak1 = now;
peaks[peakCount] = refVal;
}
else if(isMin)
{
if(peakType==0)peakType=-1;
if(peakType==1)
{
peakType=-1;
peakCount++;
justchanged=true;
}
if(peakCount<10)peaks[peakCount] = refVal;
}
if(justchanged && peakCount>2)
{ //we've transitioned. check if we can autotune based on the last peaks
double avgSeparation = (abs(peaks[peakCount-1]-peaks[peakCount-2])+abs(peaks[peakCount-2]-peaks[peakCount-3]))/2;
if( avgSeparation < 0.05*(absMax-absMin))
{
FinishUp();
running = false;
return 1;
}
}
justchanged=false;
return 0;
}
void PID_ATune::FinishUp()
{
*output = outputStart;
//we can generate tuning parameters!
Ku = 4*(2*oStep)/((absMax-absMin)*3.14159);
Pu = (double)(peak1-peak2) / 1000;
}
double PID_ATune::GetKp()
{
return controlType==1 ? 0.6 * Ku : 0.4 * Ku;
}
double PID_ATune::GetKi()
{
return controlType==1? 1.2*Ku / Pu : 0.48 * Ku / Pu; // Ki = Kc/Ti
}
double PID_ATune::GetKd()
{
return controlType==1? 0.075 * Ku * Pu : 0; //Kd = Kc * Td
}
void PID_ATune::SetOutputStep(double Step)
{
oStep = Step;
}
double PID_ATune::GetOutputStep()
{
return oStep;
}
void PID_ATune::SetControlType(int Type) //0=PI, 1=PID
{
controlType = Type;
}
int PID_ATune::GetControlType()
{
return controlType;
}
void PID_ATune::SetNoiseBand(double Band)
{
noiseBand = Band;
}
double PID_ATune::GetNoiseBand()
{
return noiseBand;
}
void PID_ATune::SetLookbackSec(int value)
{
if (value<1) value = 1;
if(value<25)
{
nLookBack = value * 4;
sampleTime = 250;
}
else
{
nLookBack = 100;
sampleTime = value*10;
}
}
int PID_ATune::GetLookbackSec()
{
return nLookBack * sampleTime / 1000;
}
PID_AutoTune_v0.h
#ifndef PID_AutoTune_v0
#define PID_AutoTune_v0
#define LIBRARY_VERSION 0.0.1
class PID_ATune
{
public:
//commonly used functions **************************************************************************
PID_ATune(double*, double*); // * Constructor. links the Autotune to a given PID
int Runtime(); // * Similar to the PID Compue function, returns non 0 when done
void Cancel(); // * Stops the AutoTune
void SetOutputStep(double); // * how far above and below the starting value will the output step?
double GetOutputStep(); //
void SetControlType(int); // * Determies if the tuning parameters returned will be PI (D=0)
int GetControlType(); // or PID. (0=PI, 1=PID)
void SetLookbackSec(int); // * how far back are we looking to identify peaks
int GetLookbackSec(); //
void SetNoiseBand(double); // * the autotune will ignore signal chatter smaller than this value
double GetNoiseBand(); // this should be acurately set
double GetKp(); // * once autotune is complete, these functions contain the
double GetKi(); // computed tuning parameters.
double GetKd(); //
private:
void FinishUp();
bool isMax, isMin;
double *input, *output;
double setpoint;
double noiseBand;
int controlType;
bool running;
unsigned long peak1, peak2, lastTime;
int sampleTime;
int nLookBack;
int peakType;
double lastInputs[101];
double peaks[10];
int peakCount;
bool justchanged;
bool justevaled;
double absMax, absMin;
double oStep;
double outputStart;
double Ku, Pu;
};
#endif
My last two errors:
PID_AutoTune_v0.cpp: In member function 'int PID_ATune::Runtime()':
PID_AutoTune_v0.cpp:35:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if((now-lastTime)<sampleTime) return false;
^
autotune.cpp: In function 'void AutoTuneHelper(boolean)':
autotune.cpp:126:36: error: invalid conversion from 'byte {aka unsigned char}' to 'PID::mode_t' [-fpermissive]
tuning = false;
^
In file included from autotune.cpp:5:0:
This looks like an error in pid library. Would you like to create an issue on GitHub to let the author know?
CREATE ISSUE
pid/pid.h:20:10: error: initializing argument 1 of 'void PID::SetMode(PID::mode_t)' [-fpermissive]
void SetMode(mode_t); // * sets PID to either MANUAL (0) or AUTOMATIC (1)
^
make[1]: *** [../build/target/user/platform-6autotune.o] Error 1
make: *** [user] Error 2
I think I get these errors because SetMode is missing a PID:: between the brackets.
But I have no idea how to add it to this line: myPID.SetMode(ATuneModeRemember);
If I change it to myPID.SetMode(PID::ATuneModeRemember);
I get the following error:
PID_AutoTune_v0.cpp: In member function 'int PID_ATune::Runtime()':
PID_AutoTune_v0.cpp:35:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if((now-lastTime)<sampleTime) return false;
^
autotune.cpp: In function 'void AutoTuneHelper(boolean)':
autotune.cpp:126:19: error: 'ATuneModeRemember' is not a member of 'PID'
tuning = false;
^
make[1]: *** [../build/target/user/platform-6autotune.o] Error 1
make: *** [user] Error 2
So any help will be greatly appreciated! 