Disclaimer

How does it work?

What PID controller does this work with?

Example code (Arduino)

#include<pidautotuner.h>voidsetup() {PIDAutotunertuner=PIDAutotuner();// Set the target value to tune to// This will depend on what you are tuning. This should be set to a value within// the usual range of the setpoint. For low-inertia systems, values at the lower// end of this range usually give better results. For anything else, start with a// value at the middle of the range.tuner.setTargetInputValue(targetInputValue);// Set the loop interval in microseconds// This must be the same as the interval the PID control loop will run attuner.setLoopInterval(loopInterval);// Set the output range// These are the minimum and maximum possible output values of whatever you are// using to control the system (Arduino analogWrite, for example, is 0-255)tuner.setOutputRange(0,255);// Set the Ziegler-Nichols tuning mode// Set it to either PIDAutotuner::ZNModeBasicPID, PIDAutotuner::ZNModeLessOvershoot,// or PIDAutotuner::ZNModeNoOvershoot. Defaults to ZNModeNoOvershoot as it is the// safest option.tuner.setZNMode(PIDAutotuner::ZNModeBasicPID);// This must be called immediately before the tuning loop// Must be called with the current time in microsecondstuner.startTuningLoop(micros());// Run a loop until tuner.isFinished() returns truelongmicroseconds;while (!tuner.isFinished()) {// This loop must run at the same speed as the PID control loop being tunedlongprevMicroseconds=microseconds;microseconds=micros();// Get input value here (temperature, encoder position, velocity, etc)doubleinput=doSomethingToGetInput();// Call tunePID() with the input value and current time in microsecondsdoubleoutput=tuner.tunePID(input,microseconds);// Set the output - tunePid() will return values within the range configured// by setOutputRange(). Don't change the value or the tuning results will be// incorrect.doSomethingToSetOutput(output);// This loop must run at the same speed as the PID control loop being tunedwhile (micros()-microseconds<loopInterval)delayMicroseconds(1);    }// Turn the output off here.doSomethingToSetOutput(0);// Get PID gains - set your PID controller's gains to thesedoublekp=tuner.getKp();doubleki=tuner.getKi();doublekd=tuner.getKd();}voidloop() {// ...}