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Unread 20-01-2011, 12:14
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Kit Gerhart Kit Gerhart is offline
Mentor, coach, whatever--
FRC #0233 ("The Pink Team")
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Join Date: Nov 2001
Rookie Year: 1996
Location: Cape Canaveral, FL USA
Posts: 559
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Re: RS550 Enough Power?

Quote:
Originally Posted by iCurtis View Post
For more anecdotal 256:1, we used them for this actuation. There were two of them (one powered the "stick" that pushes it up, the 2nd rotated it forward to lock it out. One of them was cantilevered, the other was not. The cantilevered one failed at 6:30 PM on Thursday, so we luckily got a chance to fix it without any intervening matches. We un-cantilevered the output, and it did not fail for the rest of the tournament. We never needed to replace the one which was not cantilevered to begin with. There were probably 50 cycles on the one we replaced, and 100+ on the one that was not replaced.

There was *a lot* of torque in that set up. We wouldn't do it again (apparently our lead mentors were betting in the stands on whether it would fail every single lift), but the BB did hold up. We must've used the 550 and 540, because both FPs were in the toughbox on top of the arm.

Just another data point.
We tried using one with a Fisher-Price for our arm rotation in 2007, and destroyed it instantly. In retrospect, we should have known better, given all the power of the F/P and moment of inertia of the arm.

If used properly, and with less powerful motors than the F/P, the 256:1 planetaries are fine. Also, I think the current ones are stronger than the ones we broke in '07.
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