Thread: The Game Floor
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Unread 03-01-2009, 17:35
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Re: The Game Floor

Classic model for friction does not depend on surface area.

maximum friction force F is given by the equation:

F=u*N

where u is the coefficient of friction between the two objects and N is the normal force between them.

in our case the net force that the floor is applying to the robot (the normal force) is the weight of the robot.

so:
F=u*W in our case.

so as you can classic friction does not depend on surface area.

if you were to model each wheel individually you would get a lower normal force (roughly the weight of the robot divided by the number of wheels) on each wheel so that N=W/n (W=total weight, n=number of wheels.)

so the force from each wheel would be F'=u*W/N

and we have n wheels so we get a total force of: F=F'*n=n*u*w/n=u*W

magic!

classic theory of friction breaks down in a lot of cases (for example spikes on a carpet), but should be very close to the reality in this year's game.

-Leav
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Participated in FIRST as a student: 2005-2006 (But still learning every season!)
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