Re: stepper to servo transition

Thanks for the "heads up" on mixing drives and motors. It looks
like Rutex makes a drive for hall-commutated motors:

http://www.rutex.com/us/cart.php?
target=product&action=view&product_id=16&category_id=5

@$200, this looks pretty good. And for just $100, what do you think
of getting their step/dir-->+/-10V board (R991H) which I could use
to control drives like Compumotor's TQ10, or 670T(which I can find
locally for ~$130)? For some reason, I'm a sucker for those cute
little black and yellow Parker motors that appear regularly on eBay.

re:slip rings--
Fortunately, I do not need them. I'm not particularly gifted when
it comes to mechanical stuff (like gears and transmissions). At
first, when I considered how to do this, I came to the conclusion
that slip rings would be absolutely required. But after presenting
the idea at one of the TCRG meetings, one of the guys said, "ya'
know, you don't really need slip rings..." In my usual style, I
informed him that I had given it serious thought, and he must be
wrong. He then proceeded to explain how you could transmit the
secondary axis coaxially up to a right angle gear -- sort of like
half of a differential, if that makes sense. It requires that the
secondary axis compensate for moves in the primary axis-- but this
is a trivial addition to my program. What nerve!--don't you just
hate it when people talk sense? Anyway-- this is huge plus. I had
no desire to a) purchase expensive, potentially short-lived slip
rings and b) to run encoder signals through them!

On the other hand, for rapid proof-of-concept prototyping, my
improvised slip rings were far easier than the mechanical route.

Bruce