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Unread 25-01-2011, 15:53
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Re: articulating arm help

Quote:
Originally Posted by Alan Anderson View Post
If you intend to use the motor alone to hold the arm up, without any mechanical counterweight or spring-loading, be cautious. You'll be running the motor at or near stall a lot of the time. A CIM can handle that for a while, but it will get very warm and you might want to consider a way to cool it off during or between matches.

A Fisher-Price or Banebots motor will not handle that kind of abuse well at all. They rely on an internal fan to keep their windings cool, and if they're not turning, neither is the fan. You'll melt something in short order, followed by smoke. Nearby veterans will sniff the air and nod at the familiar smell of a fried motor.
We've successfully run fisher price and banebots motors stalled at between 5-10% in order to keep mechanisms in place. The trick is to design the mechanical system such that only that little power is needed. If you do need much more then that, your motors will burn.