Eric van Es wrote:
>
> Martin R. Green wrote:
> >
> > OK, I finally have to ask...
> >
> > What's PID?
> >
> > Ignorantly yours,
> > Martin R. Green
> > elimar@bigfoot.com
> >
> Wow! Big thing to explain!
>
> What it is: A summing amp (if you like) with and proportional, integral
> and derivative input. It adds them to obtain the desired effect.
>
> Note: PID is feedback control! It is a controller that conditions your
> input to the plant, moter, etc.
>
> P: Output is proportional to the input. Basically an amplifier.
> I: Integrates the output of the system's error and applies a signal that
> will (theoretically) remedy this.
> D: Output is proportional to the rate of change of the error on the
> output of the system.
>
> This really is a major field of study - actually impossible to explain
> by e-mail! Maybe you could take a short course on control systems!
>
> Sorry I can't help more! AND I stand corrected on all of the above!
>

Have a look at these 2 articles. They give a very good intro discription
of analog and digital PIDs.

http://www.mcjournal.com/main/back/tutorial.htm

http://www.mcjournal.com/main/tutser2.htm


Enjoy.


Peter.
--
Peter Homann   email: peterh@adacel.com.au       Work : +61 3 9596-2991
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