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Unread 04-03-2004, 18:12
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Frank(Aflak) Frank(Aflak) is offline
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Join Date: Dec 2002
Location: Saint Louis
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Re: Team 1246 Rookie Bot

Quote:
Originally Posted by FadyS.
We're going to the Canadian Regional. I've already asked this before in a different thread but looking at where we placed our Globes on the bot, are there any suggestions how we can fix the backdriving problem? We can hang because we put stops after this pic so that the arms are all the way vertical without slamming back on the motors themselves, but we were having trouble getting the arm at 90 degrees with the ball where the moment is greatest. It just drops back down at that point. Also, this pic shows our temporary drive train with the fisher price. Our competitive drive train is a CIM + Bosch gearbox with 15ft/s optimal output. We were having trouble getting our gearbox in time because we sent it out to get machined so we tested our bot with the fisher prices just to get it mobile for practice and testing.

Here is what we did (actually, we designed for this, its not really a fix on our bot, its a feature!)

Here is a fix: Add about a foot of garage door spring that will be pulling your arm up. You can stretch it as far as you like, but please be careful, seeing as one of thos springs can kill. I put a cable through the middle of ours and anchored it in two non-spring related places so that in the event of a catastrophic spring mount failure, the spring won't do any damage.

It is working great for us.
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