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Unread 26-01-2010, 19:04
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VEX Robotics Engineer
AKA: Arthur Dutra IV; NERD #18
FRC #0148 (Robowranglers)
Team Role: Engineer
 
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Re: Extra CIM.... question

Quote:
Originally Posted by apalrd View Post
If you are set on using the Toughbox for the 5th CIM but are using it for non-drive, a Toughbox Nano would provide the same thing for smaller size and weight.

Toughboxes weigh alot. Weight = BAD. FRC robots are almost always right on the 120lb edge of things, and every ounce counts.
But Toughboxes can easily be lightened if you have access to a lathe. You can replace the extruded box with standoffs, and the internal gears can easily be swiss cheesed. Our favorite method of lightening the gears is to turn a .125 deep pocket into both sides on the lathe then drill six holes on the rotary table.

Of as we often do, take the gears and bearings from the Toughbox, maybe swap in different gear ratios to achieve the desired robot speed we're looking for, then design our own housing, whether CNC milled or CNC punched sheet metal.




Edit:
For high speed applications, our favorite method is to just use timing belt directly from the CIM motor drive shaft. This works good for 1:1 to 4:1 reductions. It's much quieter than roller chain at high speeds (what? it's faster than Aunt Jane at planting seeds?), and at these speeds the timing belt is pretty tolerant of loose belts.

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Art Dutra IV
Robotics Engineer, VEX Robotics, Inc., a subsidiary of Innovation First International (IFI)
Robowranglers Team 148 | GUS Robotics Team 228 (Alumni) | Rho Beta Epsilon (Alumni) | @arthurdutra

世上无难事,只怕有心人.

Last edited by artdutra04 : 26-01-2010 at 19:09.