RE: [CAD_CAM_EDM_DRO] Re:Encoder Velocity Est. - was re:GeckoDriv es.....

Ray, there are a couple of references on the Texas Instruments web site in
the motor control section search for spra363, spra415 and spra416. These are
pdf app notes for the TMS320 series DSPs. Actually I am not playing with the
TI TMS320F240 motion control chip but porting some of their assembly
language routines to the Analog Devices ADMC401 chip. I have this demented
idea that I can build up a cheap AC servo from an auto alternator by using
these chips for electronic commutation using space vector modulation that
these chips are really designed for. These chips have a built in quadrature
encoder and 3 phase programmable PWM driver that I will use to drive an
International Rectifier IRPT1058 power driver module.
Regards
John Craddock

> -----Original Message-----
> From: Ray [mailto:rehenry@...]
> Sent: Wednesday, March 21, 2001 11:15 PM
> To: CAD_CAM_EDM_DRO@yahoogroups.com
> Subject: [CAD_CAM_EDM_DRO] Re: RE: Re: Re: Re: GeckoDrives..
> Can anyone
> Help?
>
>
>
> John
>
> I saw a paper on this a year or ago. The authors built a small
> board to sit near the encoder and create a velocity signal
> from the pulse
> train. Do you know of any systems using this approach?
>
> Ray
>
> From: John Craddock <johncrad@...>
> Subject: RE: Re: Re: Re: GeckoDrives.. Can anyone Help?
>
> One can go to very low speeds with coarse grained encoders by
> swapping from
> pulse count to measuring the time interval between pulses
> below a set pulse
> repetition rate.
>
>
> Welcome to CAD_CAM_EDM_DRO@...,an unmoderated list
> for the discussion of shop built systems, for CAD, CAM, EDM, and DRO.
>
> Addresses:
> Post message: CAD_CAM_EDM_DRO@yahoogroups.com
> Subscribe: CAD_CAM_EDM_DRO-subscribe@yahoogroups.com
> Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@yahoogroups.com
> List owner: CAD_CAM_EDM_DRO-owner@yahoogroups.com, wanliker@...
> Moderator: jmelson@... timg@...
> [Moderator]
> URL to this page: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO
> bill,
> List Manager
>
> FAQ: http://www.ktmarketing.com/faq.html
>
> Your use of Yahoo! Groups is subject to

http://docs.yahoo.com/info/terms/