Microsoft has been promoting CPR by referring to competing sims' vehicle
dynamics models using the term "2D stick model." While Microsoft
doesn't mention Papyrus specifically, it is clear that Papyrus sims are
among the targets of this somewhat deprecating language.
This terminology seems to have spread among sim fans, even those who, if
they thought about it, would realize that it is misleading and
inaccurate.
I'll quote from a recent discussion on this newsgroup. A reader said:
I responded:
However. To further elaborate on the Papyrus vehicle dynamics models:
While it is true that Papyrus' current sims (except for Software Allies'
SODA) use a 2D physics model, it is completely untrue that they use a
"car on a stick" model for the player's car (though it is true that they
use such a model for the AI).
Anyone that has actually driven a current Papyrus sim would never
mistake this. Although the physics model is 2D (preventing the car from
getting airborne), Papyrus did model weight transfer due to cornering,
acceleration and braking, and separate aerodynamic downforce from the
chassis, front wing or air dam and rear wing or spoiler. This all
contributes to dynamic changes to the load applied to each tire, as well
as the yaw, pitch and roll of the chassis.
Not only is each tire modeled independently, but static and dynamic
camber changes can cause uneven contact patches with the road, leading
to uneven temperature across the surface of a single tire. These
temperatures are calculated and reported to the user in real-time.
Anyone with even a passing familiarity with setting up a race car will
tell you that knowing the inside, middle and outside temperature of each
tire is crucial to tuning the setup on a car.
Outside of the racing tire companies, Papyrus' Dave Kaemmer is possibly
the best in the world at modeling accurate tire coefficients. One only
has to review his work, and the work of his peers, to see this.
The result of the very sophisticated Papyrus vehicle dynamics model is a
car which behaves uncannily like a real race car. Very subtle things
happen at the limit of adhesion. For example, in Papyrus CART, it is
possible to use the transient oversteer due to weight transfer during
braking to rotate the car during turn-in, just as they teach you to do
at the Skip Barber Racing School. During slow and medium-speed corners,
with a good setup, I can use lift-throttle oversteer to "hook" the nose
down and point the car in towards the apex.
Another dramatic experience stands out in my mind. Almost eerily, I
experienced the car "walking" up the banking in Papyrus CART at
Milwaukee *before* I heard real drivers talking about this phenomenon in
TV interviews at the race track!
If you would like to read more about race car vehicle dynamics in racing
simulations, please see my MS-CPR review at:
http://www.simracing.com/~alison/sims/ [address restored]
You might also like to read my Overview of Vehicle Dynamics, under Setup
in the How To section.
For extremely in-depth discussions of vehicle dynamics, see the 1993
edition of Paul Van Valkenburg's classic book, "Race Car Engineering and
Mechanics", and the massive, 992-page "Race Car Vehicle Dynamics" by
Milliken and Milliken. Both of these books are available from:
Amazon Books at [link lost in import]
Barnes & Noble at [link lost in import]
Classic Motorbooks at 800/826-6600
Eagle Woman
Remove the spam blocker NOSPAM to email me.
http://www.simracing.com/~alison [address restored]
Ok......so.....what is your point?
Most likely referring to the shape of your head...I figure since
you had absolutely nothing constructive to say, that you welcome
any and all flames your way.
> Ok......so.....what is your point?
Well, I think her point is that the Papy physics aint so bad as she
first thought. And anyway, who cares. Great and informative post Alison
:) One of the best reads I've had since on this NG.
As always my newsgroup server failed to post the original message that
started this thread. Could some one email me the original post. I would like
to read Alison's great and informative post.
Thanks
John
>> Ok......so.....what is your point?
> Well, I think her point is that the Papy physics aint so bad as she
>first thought. And anyway, who cares. Great and informative post Alison
>:) One of the best reads I've had since on this NG.
>> Ok......so.....what is your point?
> Well, I think her point is that the Papy physics aint so bad as she
>first thought.
Uh, not exactly. My point is that I have *always* appreciated Papy's
physics model because of its realism and the way it accurately evoked
the sensations and behaviors I recall from racing real cars.
I should also note that Papyrus deserves a great deal of congratulations
and thanks for its superb optimization effort in making a sim that
worked so well with the processing hardware that was available in the
bad old days when ICR2 came out.
OK, sim developers: take the best of what Papy knows and the best of
what Ubisoft and Terminal Reality are bringing in, and give us paying
customers the ultimate sim!
[Editorial comment: my little brother Nate grabbed the keyboard and
wrote the above two paragraphs. Mom! He's always bullying me! Bullied
me into revising my original review, too. He even takes the best
computer whenever we race! MoOOOoooommmmm! :-) ]
I do not!
Ooh! Thanks!
Eagle Woman
Remove the spam blocker NOSPAM to email me.
http://www.nh.ultranet.com/~alison
