I was going through drivetrain basics are reread the paper Drive Train Basics (How to be sure your robot will turn). It is a really good paper explaining the formulas to calculate whether a robot will be able to turn or not. I also looked at the iLITE Drive train simulator to look at the how acceleration is calculated. Some really good stuff! The piece that was missing was the coefficient of friction for different wheels that we may use so I started doing some research and here are the details:
Hi-Grip Wheels from the KOP
These are probably the most used wheels since they are in the Kit of Parts each year. On the Australian page of AndyMark I found this:
Coefficient of friction: 0.95-1.0 static (on tight pile carpet)
Coefficient of friction on HDPE: 0.31
Pneumatic Wheels
AndyMark sells these and they appear to be very similar to the wheels we’ve purchased from Princess Auto:
CoF Forwards/backwards On Aluminum: 0.62 (fully inflated)
CoF Forwards/backwards On Poly-carbonate: 0.61 (fully inflated)
CoF Forwards/backwards On Steel: 0.49 (fully inflated)
CoF Forwards/backwards On Tight Pile Carpet: 1.27 (fully inflated)
Vex Wheels
Vex Robotics lists the coefficient of friction for most of their wheels. I’m not sure how accurate their values are as they seem to list the same value for wheels that would have a very different coefficient.
Mr. McTavish 