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Unread 15-09-2014, 23:38
Oblarg Oblarg is offline
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Re: Experience With 6 Cim Drive train

Quote:
Originally Posted by Infinity2718 View Post
Bingo! This would optimize the 6 CIM drivetrain layout with the breakers allowed.

I think people are use to the 4 CIM drivetrain gears and their limits, the 6 CIMs can take a little more than what is expected. They are two different animals.
FWIW, last year with HiGrip wheels and a 120lb (including battery) robot, we were just on the very edge of traction-limited with 6 CIMs geared to 14fps (6.1:1, 4'' wheels) - i.e., we were traction limited if literally nothing else on the robot was drawing current, else we would stall the drive. Now, admittedly, we could probably have clawed back a bit of overhead with more efficient wiring, but...

Say a 150lb robot with plaction tread (COF of ~1.3 instead of ~1). So, 14 fps * (1/1.3) * (120/150) = ~8.5fps. For a comfortable amount of overhead, I don't think I'd set my low gear for anything faster than 7.5-8. Of course, you can adjust this upwards as appropriate for a lighter robot or less-frictioney wheels, but 10 fps would almost certainly be faster than I'd be comfortable with for a max-weight robot with high-traction wheels.
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Member, FRC Team 449: 2007-2010
Drive Mechanics Lead, FRC Team 449: 2009-2010
Alumnus/Technical Mentor, FRC Team 449: 2010-Present
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