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Unread 28-03-2012, 10:52
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AKA: Patrick Freivald
FRC #1551 (The Grapes of Wrath)
Team Role: Mentor
 
Join Date: Jan 2007
Rookie Year: 2001
Location: Naples, NY
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Re: Turning on the bridge

Quote:
Originally Posted by MrBasse View Post
Where is there low friction HDPE? The polycarbonate on the bridges is quite grippy against many types of rubber wheels. That includes the kit wheels from this year, last year, and also any pneumatic wheels that may be in use. I can tell you right now, with pneumatics in the middle and omnis on the back of our bot, there wasn't a team we met that could push us sideways on a bridge (especially uphill).
Geared down 45:1 with four CIMs and roughtop tread we couldn't push many robots up the bridge even in line with their wheel base; that is to say, as long as our back wheels were on carpet we had no problem, but as soon as all four wheels were on the bridge we needed a little help. Rubber wheels likely would have worked better, but I still think it would be nigh-impossible (though not actually impossible, of course) if the robot was perpendicular to its wheel base.

We could do the math, of course, to find out what torque would be necessary -- though we'd need the coefficient of friction of both the pushing robot's wheels on polycarbonate, and the pushed robot's wheels.
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Team 1551
"The Grapes of Wrath"
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