Thread: COF help?
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Unread 17-01-2009, 19:34
writchie writchie is offline
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Re: COF help?

We get repeatable results with both the incline and pull force methods.

The conditions are new undamaged wheels and new undamaged Glassliner FRP from home depot.

We see static mu of 0.12 +- 0.02 and transverse of 0.13 +- 0.02. All measurements taken with 4 wheels.

At this point, I for one do not believe static mu of 0.05 without some form of lubrication on the floor. But those are the FRC numbers and they are sure sticking to them.

As a further aside, I cannot think of any way to traverse 48 ft of floor in 6 seconds in a standard kit bot frame without mu > 0.083, but then again I could be missing something.

In any case, we are preparing for static mu to be in the range from 0.06 to 0.15 and for the dynamic/static ratio to range from 1.0 - 2.5. As long as you can work under the full range of conditions you should be OK.