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Unread 08-12-2012, 23:22
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Re: Balancing an Arm

Quote:
Originally Posted by Tom Line View Post
As Joe said regarding our and their arm in 2011, we counterbalanced. Our gear ratio was 573 (go mechwarriors!) To 1.

We do not have facilities to make a light arm. If you look at chickens arm from the same year, they were able to fab it light enough that they used s 600:1 reduction with no counter balance.

Holding an arm in position using motors requires stalling them. If you have too much weight and draw too much current, you will fry them. You can always gear down, but then you are trading off on speed
Our 2012 arm drew around 4 amps when stalled, holding the arm horizontal. This was around 1 volt. We never had a problem dissipating 4 watts.