Force feedback integration : need help about physics

Hi, all.

Currently working on force feedback integration in Torcs,
I am very close to the moment when I'm able to inject some effects
into my wheel.

But now, it's time to really think about :
1) what effects we want to render in the drivers hands
    (let's list them all ; we'll see later if we can, depending on the FF device)
2) what forces / moments computed into the physics simulation engines
    (simu V2 and simu V3) we can use to set effects / effects parameters ;
    and may be there is a need to compute other ones ?
3) how we get these forces / moments from the simu interface
    to the human driver module.

I have some very small ideas about that, but really need your input :

1) - increase the steering counter-force with speed
      (more and more hard to steer when speed increases,
       linked to wheels' inertia, and also active steering systems)
    - provide some vibrations when rolling on kerbs,
      but also on sand, grass, ... or bumpy road / track
      (we have data about the ground under each wheel,
       but can we have / compute realistic "vibration" frequencies
       for these different grounds, apart from the real bums/holes ?)
    - even provide shocks when hardly bumping on kerbs
    - is there a way to make the driver feel in its hands
      * the spinning of the front wheels for front wheel drive cars
      * the sliding of these wheels when the car under-steers

2) Racer <http://www.racer.nl> : they use
    * the steering wheels/tires aligning torque, computed through a Pacejka
      model, to inject a constant force effect,
    * the speed of the car and the "force applied by the ground
      on the steering wheels/tires", when one roll on a kerb,
      to inject a periodic force effect

    Vdrift <http://vdrift.net> is at the very beginning, only testing ...

3) After a quick look into car.h, I don't understand many details,
    but I feel that we lack some variables here to make the job ...
    Then, looking further into simuV2/V3, I found many more computed variables,
    but I don't see clearly the ones that could we exported ...
    even if some have a nice name, like "feedback", "raeaction", "Inertia", ...

I'm pretty sure some of you guys have very precise ideas about all this ...

Your help would be greatly appreciated !

Cheers, Jean-Philippe.

PS: As far as libs, compilation, ... that is code is concerned, I'm working
     with the very promising open source library OIS <www.wreckedgames.com>,
     that already provides force feedback under Windows (R 1.2.0)
     in a very close future under Linux (there is a published patch
     on the forum), but not under Mac OS for the moment, even if the
     infrastructure is ready now.

     My opinion is that when Torcs is ported to SDL (isn't it already ?),
     we have the opportunity to get rid of Plib/js and replace it by OIS,
     that already ships a SDL input manager ... so, no supplementary dependency !

     When I have something working, you'll get the patch and the HOW-TO-BUILD
     (if you are interested, of course).

-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/