Re: [CAD_CAM_EDM_DRO] Re: Dedicated mb for PID

Yup that is pretty much it. We map it to the z plane for discrete systems.
Also note that sD blows up with high frequencies; I/s blows up approaching
DC (s=0) so a practical system has to have a few more terms in it.

Convolutions are pretty easy.. just a double nested loop in the
simplest form.

Two motion control chips that are hard coded for this are
the National LM 628 and the HP HTCL-1100.

Les

Leslie Watts
L M Watts Furniture
Tiger, Georgia USA
http://www.rabun.net/~leswatts/wattsfurniturewp.html
engineering page:
http://www.rabun.net/~leswatts/shop.html

----- Original Message -----
From: "Doug Harrison" <prototype@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: Sunday, June 30, 2002 12:37 PM
Subject: Re: [CAD_CAM_EDM_DRO] Re: Dedicated mb for PID


> Since operating frequencies are generally below 100Hz (6Krpm) it is
possible
> to use a greatly simplified continuous model as an accurate approximation.
> It's been a long time since me and LaPlace was drinking buddies but the
> Galil filter looks to be a transfer function -
>
> F(s) = P + sD + I/s
>
> Some algorithms for convolution of the FIR filter are given in Numerical
> Recipes for Fortran. They don't appear to be compute intensive.
>
> Doug
>
>