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Unread 10-12-2007, 03:57
Lil' Lavery Lil' Lavery is offline
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AKA: Sean Lavery
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Re: compact transmission

Quote:
Originally Posted by Aren_Hill View Post
A. The output shaft needs to be vertical
B. It would need to accommodate 2 small cims and maybe a big one also
C. It needs to be as short as possible meaning from the back of the motors to the outer plate of the transmission, hopefully around 6 inches in total length, I forget the length of a cim but the shorter the better
D. 3 or more speeds capable of being shifted without pneumatics, servo's or one of the small motors in the kit will be used. preferably servo's
E. customizable ratios.

Any advice?
The best piece of advice I can give you is, ease up on your constraints. What you're asking right now is rather unrealistic for use on a FIRST robot. Ignoring the DeWalt transmission, 3+ speed transmissions have been rather large (same with any multi-speed for that matter) compared to your current requests. Here are a handful of links to pictures/white-papers on various 3/4 speed transmission used by FIRST teams in the past, each of which violate one or more of your design constraints.
http://www.chiefdelphi.com/media/papers/1580
http://www.chiefdelphi.com/media/photos/26744
http://www.chiefdelphi.com/media/photos/26830
http://www.chiefdelphi.com/media/photos/17476
http://www.chiefdelphi.com/media/photos/17478
http://www.chiefdelphi.com/media/papers/1539

Good luck, and I certainly hope you can pull off your design successfully at your current restraints, and I hop these pictures provide some helpful hints into possible directions to pursue.
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