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Unread 04-01-2009, 13:15
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Re: Frictional Discrepancies

Quote:
Originally Posted by Tristan Lall View Post
There's an order of magnitude between the two sets of published figures (for the inline case, assuming that's how AndyMark tested them). This makes design difficult.

Any guesses as to which is accurate? I'd surmise that AndyMark tested early-production wheels, and that FIRST is quoting from a generic material specification, but that's entirely speculative.
I think it's pretty clear that the AndyMark numbers are wrong. From what I remember of previous years with rubber on carpet, a mu of .6 or so was decent, and more than .9 was absolutely amazing. Mu of 0.5 would be only a small step down.
The numbers FIRST quoted sound like they were derived from testing, given that the manual has both inline and transverse coefficients.
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