Re: servo hunting

Hi,
You may already know about this link but check it it if you don't..
http://www.isomedia.com/homes/billmw/
Has a servo system, and is real helpful..
regards
Hans Wedemeyer

Elliot Burke wrote:

> My experience with servos is limited, so I'll ask the group here:
> If a servo is controlled digitally, is it inevitable or even usual
> that it
> will hunt between two adjacent values? The situation envisioned is if
> the
> encoder is at a point where it near a transition between two values,
> will
> noise or other causes make it switch between them?
> If this is so, then why wouldn't hysterisis be used to prevent this?
>
> A colleague is using microsteppers and having great difficulties
> getting
> quiet positioning. The residual vibration level of desired is in the
> sub
> microinch level. Positioning accuracy or precision doesn't have to be
> that
> low, he just doesn't want it moving around once he puts it somewhere.
>
> Elliot Burke
>
>
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