The online racing simulator
Searching in All forums
(20 results)
Nikn
awesome!
Nikn
Being a software developer and having my own projects I understand how it can be very hard to make progress past a certain point. I have to say, LFS is damn impressive for a 2-3 man team even after all these years. Keep working at it an a breakthrough will come soon enough! It's exciting to hear that the team hasn't given up.

On a side note, since LFS came out computing power and network bandwidth has gone way up. I can envision a multithreaded tyre model, shader based global illumination, and tons of other cool stuff being feasible all at the same time now!
Nikn
Quote from AndRand :top 3d chart is result (vector sum) of charts below.

Okay, your graph is actually sort of making sense. Basically here's the deal. The data you uses measures combined SR and SA up to some value. The corner of the graph represents unmeasured values of SR and SA that you are interpolating. You are "guesstimating" that more combined SR and SA = less force, when in reality as slip becomes really big in either direction your force reaches a steady magnitude point in the SVx, SVy direction.

So I just tried making my own formulas (not pacejka) and ran into a similar issue as you. (falling off at the corners) so I just added an effect where Fx,Fy are just the naive Fx,Fy you get from the friction circle at very high values of slip. You can see the "ugly" effect in the 3d chart, but the feel might actually not be soo bad. Check it out:
Nikn
The coefficient's are from pacejka's book (http://www.flipkart.com/book/t ... namics-pacejka/0750669187) but four of the coefficients were missing so I guesstimated those. The data they are based off of is empirical but judging from the curves they only measured slip angles up to about 8 degrees (doesn't capture falling off of force at higher slip)

I went to the local engineering library and looked at some more recent literature (2004,2007) on tyre modelling.

Two new articles of interest... apparently speed has a huge effect on slip angle vs Fy curves!!! At low speed the tyre is much more forgiving than at higher speeds... kind of intuitive actually.

I also noticed you mentioned transient response early - this is actually very easy to add from a programming perspective. You simply create a 2DOF spring connecting the tyre to the suspension point where it is supposed to be mounted. The tyre forces move only the tyre and the suspension will be affected by the forces in the connecting spring (instead of the tyre forces directly affecting the suspension).
Nikn
that seems odd.

here is a picture of what a pacejka combined force plot looks like. (some of the params might be a tiny bit off) for some random 195/65/15 tyre

the quality is a bit bad.

Red = greater magnitude, Green = less magnitude, used blue to show band lines. an interesting note is that it's not symmetrical over braking and acceleration.
Nikn
very interesting thread. There's a lot of good literature out there on tyre modeling. Here's two I found:

Understanding Parameters Influencing Tyre Modeling:
http://www.engr.colostate.edu/ ... ing%20Tire%20Modeling.pdf

Mechanics of Pneumatic Tyres:
http://media.wiley.com/product ... 9/04713546/0471354619.pdf

Even if the equations become too confusing, most of the papers out there still contain a lot of partial experiment data that would help a lot when making your own model.

Nikn
If you want it to look a lot more bumpy, turn up the 1g vertical shift and all the 1g shifts in the views option. I'm not sure, but I think they might be set to 0 by default.

Definitely, there needs to be some kind of sound generated when you run over a bump or when the suspension compresses.
Last edited by Nikn, .
Nikn
lol funny
Nikn
i drive a 91 mr2 turbo, and i can say that cruising at 80 mph generates some boost. then again, my turbo is pretty small, but its also pretty dead. i think the original suggestion is valid.
Nikn

Watch that, I see no oversteer at all not even when going over curbs also (i cant find it now) i saw a video of the same F1 car going round an oval and the driver cut the corner went straight over the grass full throttle! This is a game not a simulator

it is probably not being played in simulation mode and assists are likely on?
Nikn
+1

its probably also easy to implement
Nikn
Quote from Jakg : show him a car that has more than 36 degrees of lock stock, and he'll do it

show me a production car that comes with 4 different types of LSD, fully adjustable suspension and nearly infinitely many gear ratios.
Nikn
Why do people say "LFS is a SIM, not an RPG"... An RPG can have SIM aspects and vice versa, things don't have to be so black and white.
Nikn
When damage is more carefully implemented, this could shine. In my opinion it would be sweet if you had to pay for tyres too. In most amateur racing this is the biggest cost. Role playing aspects make any game more fun and addictive.

...As a side note, having NFS ricey stuff to put on your car like premade decals, body kits, rims, wingS, neons, etc would be kind of FUN. Nothing that affects performance, just stuff to express your personality. This way we can spot for sure the n00bs before they even finish a lap >:]
Nikn
Sorry to hijack post, but does anyone think the RAC rear wheels aren't wide enough?
2 step launch control
Nikn
A lot of turbo race cars use a 2-step rev limiter that sets a lower rev limit when both clutch and gas are fully pressed in. The rev limit is also usually an ignition cut as opposed to a the usual fuel cut limiter. The result is fuel still being injected and exploding in the exhaust. There is a lot of exhaust noise, sometimes flames.

It helps with launches by building full boost at reasonable RPMs. It also maintains a desired RPM for launching.

If we added this to LFS, it would help the turbo GTRs. I think its a bit more realistic, and it will also allow higher 1rst gear ratios for turbos.

Here is a video example: http://www.youtube.com/watch?v=v922aYoFcyY

what do u guys think?
Nikn
Adding some sort of mountain road would definately make the content of LFS much more broad while still allowing the game to focus on realistic online racing. It would also be a first for any realistic online sim i believe. I just wonder if making such a track would suck up all the dev's time...

to quote the lfs website's faq: "A wide variety of cars and tracks is planned and our goal is to cover any type of racing. " i think they should and will include a tarmac rally stage in the future.
Nikn
If anyone has some models to show please do. Maybe if there is some good content the devs will get inspired enough to add your content.
Nikn
Not too much new. I still need to get a copy of 3dsmax for this computer . Anyways, MAGGOT can i see your model?