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Unread 25-01-2011, 14:54
AustinSchuh AustinSchuh is offline
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FRC #0971 (Spartan Robotics) #254 (The Cheesy Poofs)
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Re: articulating arm help

Quote:
Originally Posted by HarveyAce View Post
Should we just use two there and use a cim to power the arm?
You can still use the BB for the arm, but understand that the BB will not like being anywhere near stall for any significant period of time. This means that you should design the torque that the motor needs to apply to keep the arm up to be significantly less than the stall torque (1/4 or less of the stall torque. I don't have a good number for this). Adding a second BB if it looks like it'll take much torque on the motor to keep the arm up will help. It wouldn't hurt to also put a fan blowing across the motor to cool it when it isn't spinning.

971 used 2 FP motors in a single joint arm in 2008, and it worked just fine. We had way too much power in the joint, which meant that the motors weren't loaded very highly.