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Unread 26-05-2014, 09:30
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Re: Physics of T-boning

If you are going to have a physics discussion about T-boning, some discussion about the Traction Circle should be brought up. Basically, for a wheel to carpet that has consistent traction (say colson), the effective CoF (coefficient of friction) in lateral and longitudinal are teh same. Then you get into sliding conditions, the effective CoF follows a circle. thus if you are eqaul side slip as longitudinal then the effective CoF of either component direction is reduced to square root of 2 or 0.707.

This video does a decent job of describing:
https://www.youtube.com/watch?v=JjCcFsGLpaM

Another item needs to be static vs. dynaminc CoF. Once you get into a slipping/sliding condition, you are in the Dynaminc CoF which is lower than static. thus you have a dramatic reduction. (10-30% reduction depending on surfaces and materials).

Lastly, you need to look at the torque it would take to pull off of the "T". This one is a little trickier. I will see if I can draw something up about this one. Ultimately though, CG placement for-aft will mean taht the robot stands a decent chance of pulling out in one direction, and no chance in the other direction (assuming the CG is not the exact midpoint.