Greetings all. My kids have been begging me to build some kind of
robot. I'm thinking of something like an 18" square platform (wood,
initially), cruising around via radio control from my main computer
setup. It'll have an ultrasonic ranger (that I've already built) on
it, a PIC to talk (via RF, I've already got that part done) to the
computer, etc. The place where I'm stuck is the motors. I'm thinking
of two drive wheels, each with its own PWM-controlled motor with a
sensor to measure how fast and how far each one has rotated. So what
I need are two fairly hefty, 12-Vdc motors, reversible. I have an old
windshield wiper motor from a former car, but it seems (?) to have
the field in series with the armature (?)... at any rate, I can't
get it to go in reverse, which is crucial since if I use two matching
motors, one will have to go one way (CW, say), while the other goes
the other way (CCW). It doesn't need to go very fast...60 RPM or so
would be fine.

Any advice? Pointers to advice? I suppose it should go without saying
that I don't want to spend much money on these things, so any hints
on finding them used or otherwise cheap would be much appreciated
(the reason I thought of windshield wiper motors is that I figured
I could get them from a junkyard).

Thank in advance!

Michael

Thank you for reading my little posting.


_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.