Physics Modelling

[smurfer]

Hello all,

is there any thread or page that explains the detail of physics modelling?

I'm for example most interested in the question, if tire flex is modelled (if not visually, then maybe physically), since tire pressure and flex is quite important for offroad driving, I guess.

Cheers, smurfer

[Sneaksie]

You can adjust tire pressure, so yes (but visually a wheel stays the same).

[smurfer]

Thanks for the prompt answer.

Does this pressure adjustment just represent an additional kind of spring-damper element orthogonal to the contact point or is lateral tire flex also modelled?

[Sneaksie]

AFAIK it affects wheel grip, a car will skid in deep mud on fully inflated tires. I'm not sure that tire flex effect is being calculated using an accurate physical model, more likely some 'grip' parameter is directly adjusted. To my knowledge, there are no simulations that model every effect true-to-life using mathematical modeling on the market though, especially no offroad ones.

[smurfer]

Thanks for your input again.

To my knowledge, there are no simulations that model every effect true-to-life using mathematical modeling on the market though, especially no offroad ones.

You're right, there is no mathematically perfect model. Nevertheless, there are several simulations with quite advanced tire models based on Pacejka (like racer) or own systems, like Live for Speed (see below). You could count Richard Burns Rallye as offroad, it also follows a complex mathematical model to simulate tire flex (though not visually modelled). LFS' tire flex (http://www.youtube.com/watch?v=uAh3fQ1d1Ek)

But don't get me wrong, I don't want to compare or judge, I'm just curious :)