How Does DDWFTTW Work and What Are Its Key Principles?

[Dale]

In articles about vehicle dynamics (try a web search for "vehicle dynamics contact patch"), contact patch is often used as a dynamic term, and in this context, the contact patch moves with the vehicle (it has the same velocity wrt ground). There are also statements made about how the tread surface in a tire deforms as it flows through the contact patch, yet another dynamic usage of the term contact patch.

OK, that makes the terminology confusing, but that happens sometimes. The important velocity for determining work is the velocity of the material in the contact patch (which is equal to the velocity of the ground assuming rolling without slipping), not the velocity of the "vehicle dynamics contact patch" (which is equal to the velocity of the vehicle under standard assumptions).

the static friction force between tire and road can perform work

Yes, in a frame where the ground is moving.

 

[Dale]

I think that it is time to close the thread permanently. I tried to keep it open to support our good members, but it seems to be full of physics misunderstandings which I think are too muddled now to continue.