Thread: pic: Traction test
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Unread 08-01-2009, 00:30
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Re: pic: Traction test
Just so you know, surface area in no way at all effects friction. It can effect traction though where traction is the sum of all forces you use to propel your robot. One non friction force that is included in traction is "Gripping" force. Carpet to rubber has "gripping" force which is caused by the carpet meshing like gears with the rubber. "Gripping" force is effected by surface area, more grip points more resistance. On this years surfaces, however, it is only friction.

The reason friction does not go up with surface area is that as you add contact point the weight per point (pressure) goes down, netting a even friction force. The formula for friction Ff=µ(Fn). Where Ff is Force of friction, µ is coefficient of friction and Fn is normal force (is this case weight of the robot). Te left robot most of one because of discrepancies in the wheels that made it have slightly more friction with the floor

tl;dr: Surface area doesn't effect friction, winning robot was blind luck.
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Last edited by Woody1458 : 08-01-2009 at 00:33.
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