Re: Low cost Servo Controller

Oops, my last post didn't come through.

Jon,

The center of mass and center of percussion of the structure are far from the spindle so the 800 lbs
inertia /gravity force will tend to more stress the base which is built into the floor.

I will put some pictures on the web site as soon as the z axis is mounted to the y axis. Right now
I am cleaning up and installing a Boxford VSL lathe with Themac tool post grinder to expedite
the ballscrew end machining.

Anyway the structure is built so the deflections will be what they will be. It is the most rigid
that budget and engineering analysis will allow.

I would like to learn what the best controls will allow as far as high speed performance. My lm628
software was tested with a small xyz voice coil driven machine and the very best I can do (following
tech80 advice) is 1000 microsecond trajectory updates. If EMC can do 200 microsecond servo
updates I would think one could go 5 times faster or one fifth following error given the proper
amp and encoder. Perhaps even better considering feedforward.



--
Leslie M.Watts
Illinois Tool Works
Corporate Advanced Technology group
(847) 657-4559
http://www.netcom.com/~leswatts/leswp.html