[ODE] Vehicle Gears/DriveDrain/Engine techniques.

[Ruud van Gaal]

> > yes there will be an analog gas pedal involved.
> 
> I'm getting there as well.. soon. But I don't have access to 
> any analog input devices, unfortunately..

Your mouse is an analog device...
I use my mouse all the time while testing my carsim.

Ruud

> Something my car sim scream for is a better "tire model", ie. 
> friction circles/curves and stuff. The friction approximation 
> ODE uses just don't seem to cut it in my case, the car 
> behaves very oddly when wheel slippage is occuring.

Indeed, don't use ODE's friction model; it really has nothing to do with
tires.
Try Pacejka's tire model, or any other SAE models that also do the
trick.
Get 'Race Car Vehicle Dynamics' from Milliken & Milliken; it shows you
the curves involved.
The Pacejka model approximates the road reaction forces (thus the
driving forces).
Visit rec.autos.simulators; there you'll find answers to your
questions... (Google for old 'Car physics' threads).

> I haven't looked into it yet, but how hard would it be to 
> implement a different friction approximation? That is, some 
> kind of gradual blend from static friction to sliding friction?

There is no static & sliding friction with tires; those are irrelevant
there.
Driving forces are related to the velocity ratio, not slip velocity
itself.
So a simple model is to take wheel world velocity, and contact patch
velocity (due to the wheel spinning). That ratio is the input for the
tire force formula. (longitudinally)

> For great info on car simulation programming, check 
> http://www.racer.nl/

Ah, yes. :) My little baby, lol.

Ruud