Encoders

[Duane R Balvage]

  Hi All -


  > > The steppers have a "cogging" sensation when you rotate their shafts -
> > would make for a nice feedback.  As for absolute position, this can be
> > done through software - reset this control and it is *now* sitting at
> > zero.
>Then again, assuming that you're simulating pots and not allowing more
>than one rotation then all that's needed is an end stop. Since you're
>using *motors* then
>you can just drive them all against this stop at power on. This also
>allows for 
>proper recall of knob position when recalling stored presets.
>Just arrange for powering the motors as well as sensing the pulses, and
>bingo!
>... not that I'd like to design it or anything :-)


>Robin.


   OR, you could use servomotors - the servos could sense position as well 

  as be feedback to let the motor know where to stop. (I think that's how

  automated mixing desks work ... I could be wrong, tho' :) ) Kinda expensive,

  but, if you "need" that kinda control, you play, you pay. It's kind of like

  cars - a Ford Escort will get you there, neither quickly or with class,but

  it WILL get you there (usually), where a Porsche gets you there quickly

  and with CLASS. Of course, the Escort costs $8,000 , and the Porsche costs

  $80,000. It just comes down to what you want, and what you can afford (which

  USUALLY are on opposite sides of the universe!) Anyways, that's my .02 worth.


                                          Duane


                                           _-___-_---_synth nut
-- 
         
  "Two nothings is nothing, thats mathematics, son...." - Foghorn Leghorn  
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