Rollovers since 1.3? (take a look, Aristotelis)

[chaostheory]

When you do see a Formula Renault car take one of those curbs (by accident) it completely unsettles the car so they lose a load of time, & I think they could launch the car as the original nKPro video's posted showed. Take for example the Singapore sling, during a recent KS2 event we saw the same behaviour as in F1, with many people doing a Kobayashi when taking too much right hand curb. I have had some strange rolls in 1.3, but can't say for certain it was the sims fault, as normally when you know that's gonna happen you don't make the same error again or if you do your ready for it =)

Hi CAR.

I think there's a difference between touching the kerb with the wheels and doing it with the underside (like kobayashi)...

The problem I mention have nothing to do with the second one. I'm sure physics work well in this particular case, throwing up the car like we see in the chicane with kobayashi.

I would say more: I'm sure the physics work well when you are throwed with a 'high' roll angle after touching a high curb with the inner wheels at high speed (like in the first netkar examples of the thread)*

Where I think the problem is, is in the behaviour of the car when it is in two wheels.

I can imagine a single seater in the real world rolled about 30 deg. after an unfortunate line in the corner (i take again the track of your example to show you what I mean. See around 1:24. Sorry about the music)

http://www.youtube.com/watch?v=xiajTEeyGeI

What I cannot imagine is a single seater in the real world rolled about 30 deg. with enough grip on his tires to complete the rollover, an that's exactly what happens in netkar.

See again the first video of the thread. At 0:27

http://imageshack.us/photo/my-images/6/rollovery.jpg/

At this point, the car is on the maximum roll angle that was caused enterely by the impulse of the kerb, and the angular velocity is almost zero at this point. Everything working right up to now...

But if you see the video carefully, without changing the steering angle, the car then continues the rolling.

The car is in the point where I think it should have almost no grip in the tires touching the road. At least not enough to allow cornering like it does. Even if the tires find the optimum slip angle, the area in contact should be a few cm^2. This brings us to the plot in the first post (coeff. friction - vertical load). If we add the fact that we have a very small area in contact with the road... Tires are very loaded at this point, but the mass of the vehicle is the same, so less overall grip have to deal with a force I think is impossible to be generated, and it is the force you need to make the green vector (image 2.2 in the first post) long enough to force the center of gravity to go beyond the vertical of the contact point and put the car upside down.

Where the tires get the grip from to do this (by generating cornering (centripetal) force)?

*Maybe sometimes the "problem" is the scaling of the curbs compared with the real ones...

[Guest CAR]

*Maybe sometimes the "problem" is the scaling of the curbs compared with the real ones...

I think that's an important point, maybe if we had the FVA tracks we could make comparable comparisons, but with fictional tracks & community content (which's on the whole conversions) that makes it difficult to draw a conclusion. For example with the ver. of Singapore used for a league event we had to spend a lot of time raising the curbs & getting them just right for nKPro. On the other hand you normally have to flatten bumps for nKPro.

Edited October 7, 2011 by CAR

[chaostheory]

*Maybe sometimes the "problem" is the scaling of the curbs compared with the real ones...

I think that's an important point, maybe if we had the FVA tracks we could make comparable comparisons, but with fictional tracks & community content (which's on the whole conversions) that makes it difficult to draw a conclusion. For example with the ver. of Singapore used for a league event we had to spend a lot of time raising the curbs & getting them just right for nKPro. On the other hand you normally have to flatten bumps for nKPro.

Of couse, but the fact that the average height of the curbs in the real tracks is different from the netkar pro ones doesn't mean that a real car would rollover in a curb like this one, whose height is a fraction of the wheel radius.

[Guest McSaltens]

depends on how much lateral g load are you putting, and the jump it gives by going over the krub in this particular picture, if you go like 180kmh with lateral g about 2 maybe would be possible. obviously in that corner you are on 3rd gear about 150kmh, probably not enough to roll it over. but that kerb is really high!

[chaostheory]

depends on how much lateral g load are you putting, and the jump it gives by going over the krub in this particular picture, if you go like 180kmh with lateral g about 2 maybe would be possible. obviously in that corner you are on 3rd gear about 150kmh, probably not enough to roll it over. but that kerb is really high!

Hi,

It is not my intention to seem redundant, but as I see the forum is almost dead, I'll reopen the discussion with a new point of view.

In the last (and only) indian F1 GP, we could see Massa broke twice his suspension because of a "high speed - high g load hit with a 'high kerb'" (not as high as newbury).

Qualy:

http://www.youtube.com/watch?v=zkzDwtskw04

Race (2:10):

http://www.youtube.com/watch?v=xfXAgf5lyAk

Don't you guys think this is more likely to happen, long before the car starts can roll enough to rollover?

Keep in mind that being at 'high g load' (more than around 1G), means the aerodynamic grip is at least 'relevant'. So aerodynamic lift is another force we have to add in opposition to the roll moment.

That's maybe the main reason because Massa broke his suspension before the car could roll.

Relatively low speed, as said McSaltens, would not allow to rollover because of low G and low impact, and relatively high speed would not allow to rollover because high Lift (up to two times the weight in a F2000 maybe?)

I don't know if I'm right, but I know I never saw a formula "try to" rollover.

Of course, my think is that if Massa would have hit higher kerbs, the same would have happened (once you have broken the suspension, the roll moment won, but it ceases because there are no longer lever arm).

In past Netkar Pro releases there was a more sensible damage model, but I don't know the difficulty of implementing something like that, but I still think that "to not break" the suspension is a more realistic reason to avoid kurbs than "to not rollover".

So what do you think?

[Guest CAR]

Massa broke his suspension twice because he lacks accuracy (I'm not being harsh as it's well known he takes different lines lap after lap). This is an interesting video:

http://www.youtube.com/watch?v=kgx0PrnL34U

If that happened in a game you'd (all of us) probably be swearing about how unrealistic it's

[Guest sluggy]

I just want to share my experience with this issue. I have driven few laps at Blackwood and rolled over both with f2000 and KS2 in second corner before finish. According to replays it seems nKP simulates gravity correctly only to certain distance above ground. If the car takes off, it behaves like feather in the air. On the other hand car handling on crests is very nature. I recommend to try Knutstorp circuit with Abarth.

[chaostheory]

Massa broke his suspension twice because he lacks accuracy (I'm not being harsh as it's well known he takes different lines lap after lap). This is an interesting video:

If that happened in a game you'd (all of us) probably be swearing about how unrealistic it's

That's a good find!

Now it's proven that a F3 can rollover in a kerb...

But still, as you know, it's a different situation. Here aerodynamic lift is inverted when the car changes his attitude, but when rolling around the longitudinal axe, the car keeps pointing the flow direction.

I just want to share my experience with this issue. I have driven few laps at Blackwood and rolled over both with f2000 and KS2 in second corner before finish. According to replays it seems nKP simulates gravity correctly only to certain distance above ground. If the car takes off, it behaves like feather in the air. On the other hand car handling on crests is very nature. I recommend to try Knutstorp circuit with Abarth.

That's the reason why I thing the "bug" (if it is) must be related with tire grip at extreme attitudes. Mass and gravity acceleration related algorythms seem perfectly well implemented. I love the crests at "the ring"...