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Unread 09-01-2007, 09:32
Justin M. Justin M. is offline
Mechanical/Driver
FRC #0321 (RoboLancers)
Team Role: Mechanical
 
Join Date: Jan 2005
Rookie Year: 2005
Location: Philadelphia, PA
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Re: Using two CIMs in the Banebots Transmission

Quote:
Originally Posted by Joe Johnson View Post
This is an age old design choice. In general, I come down on the chain between the wheels camp rather than independently driving each wheel. It boils down to this: When you are pushing against another robot, your front wheels tend to lift and your back wheels tend to get more weight on them. This means that your front wheels are likely slipping and your back wheels are doing most of the pushing. In the independently driven wheels case, only your back motors are doing any useful pushing. This is not why you wanted 4 motor drive! So... whether you buy 2 planetary gearboxes or buy the adaptor to drive 1 planetary gearbox with 2 CIMs, I highly recommend that you consider having chain link all your wheels (and by the way the right number of drive wheels is 6 -- FYI).

Joe J.

P.S. It is my considered opinion that the Banebot 56mm gearbox is sufficiently over designed for 1 CIM motor that it can easily accept the load of 2 CIMs. In fact, I think it be converted to accept 2 CIMs AND a Fisher Price in case you are in the Team 25 Camp (a.k.a. The 3-Motors-Per-Side-Minimum Camp)
Thanks for the tip. I was considering doing that to distrubute pushing power among all the wheels. Just run a chain from the output shaft to the wheels, then attach an additional sprocket to the opposite side of the wheel, and run a chain connecting the two wheels together with the same size sprockets.
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Last edited by Justin M. : 09-01-2007 at 09:35.