Chief Delphi - PID Control

Quote:

Originally Posted by virtuald (Post 897097)

I made a spreadsheet to model an ideal PID system. Its useful for understanding some of the basics, and how changing the parameters affects the output of the system.

http://www.virtualroadside.com/blog/...n-spreadsheet/

Dustin,

Your spreadsheet looks cool, but have you stopped to think what is this "position" you're calculating? Is the spreadsheet a) simply a way of showing how the P, I and D gains of the controller change the step response of the closed loop system with a particular plant (in your case, an integrator), or b) a simulator to predict how the PID controller will affect "a system" whatever it may be, from a steam locomotive speed or airplane roll to a FIRST robot's arm?

The answer it a), of course, and it is important to know the difference and clearly state it. If a student downloads your file and then uses it to tune his team's robot arm/speed/position control not understanding what exactly this spreadsheet does - obviously it is not magic as to work for every plant in the world -, he could come up with an unstable or severely oscillatory system, damaging equipment or worse, getting injured; at the very best, he'll be frustrated the robot doesn't behave the way it is expected to. With that disclaimer, I believe your spreadsheet can be useful in teaching students the basics of PID control.