“ are rfactor2 physics broken” video

Discussion in 'General Discussion' started by GTClub_wajdi, Dec 29, 2020.

  1. Nieubermesch

    Nieubermesch Registered

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    What I've said also means that none of the physics aspects is totally off, just in conjunction it can create the feeling something is off with each individual aspect.
     
  2. Andrew Hollom

    Andrew Hollom Registered

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    Do you think it might be something simple (and silly) like the force from the tyre's contact patch slip angle being assumed to be purely lateral force rather than being resolved into longitudinal and lateral forces? In other words, is it the drag due to scrub that's missing?
     
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  3. davehenrie

    davehenrie Registered

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    Cant add anything constructive except to remind the one guy who felt the tires did not drop off fast enough. After the virtual 24, a Michelin spokesman liked the tires EXCEPT that they dropped ofcourse to quicklyand too much
    He talked about loosing tenths per lap at Le Mans over a full stint instead of second(s) per stint as the rF2 tire does.
     
  4. mantasisg

    mantasisg Registered

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    Well that was quite straight forward, nothing complex about that observation and most importantly coming from no one else, but the Michelin. Same thing was also observed by community much earlier. And was it addressed in rF2 so far ? But this should be in update soon to come, or it isn't to be expected ?

    Who control these things in rF2 ?
     
  5. Andrew Hollom

    Andrew Hollom Registered

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    I've not tried, but does running a car with extreme toe angle negatively impact its top speed? If not, then I suspect the forces are being incorrectly resolved. If the angle is small, then the error is small, so is easy to overlook, but this is what we used to call a school boy error though, so surely not.
     
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  6. Nieubermesch

    Nieubermesch Registered

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    Yeah, might try that after. I am sure it's being considered. Tyres scrubbing also seem to make car lose speed, what I was getting into was more of the dynamics of the aftermath of that. It's too complex of a subject to say anything with any certainty for me though. Better people can comment more on what I've said.
     
  7. ATQ

    ATQ Registered

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    Looks to me the car has a ton of grip and sharp handling - biting back all the time because it doesn't like the treatment. That's how I would expect it to behave. It's only when the tires are overheated that it slides more easily.
    My guess is (don't own the car so can't test it) that if you were to try proper drifting it would be very difficult. In the video it looks like you're going too slow, abusing the car so it shifts between understeer and oversteer. If you send it into oversteer at higher speed (flick, clutch kick or shift lock - whatever works) I think it would be very difficult to catch the slide.

    I could not find any videos on LMP cars drifting but here are some F1 cars going sideways.
     
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  8. ATQ

    ATQ Registered

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    I think it was Colin Chapman who said of Ronnie Peterson that it was very difficult to set up the car for him. Ronnie would just tell the engineers something like "the car slides too much". When asked at what end the car looses grip first and if it's at the entry, mid corner or exit, he would just go "I dunno...". Then Ronnie would drive around any problem and consistently hit the same lap times, no matter the setup.

    So yeah, being a racecar driver doesn't necessarily mean you have a good understanding of these things. Besides, when driving a real car you're not likely to try all the crazy stuff you would in a sim. That could get very expensive and hurt a lot.
     
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  9. Slip_Angel

    Slip_Angel Registered

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    I know that effect, but in RF2 the ratio between the loss of speed due to scrubbing and gain of grip is quite off.
    You don't lose significant speed(sometimes it actually stays at constant speed) at excessive steering angle BUT you gain good chunk of grip back.

    so scrubbing costs so little speed penalty for grip and end result is you are finishing the cornering without big consequences as you expect from such technique.
     
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  10. Nieubermesch

    Nieubermesch Registered

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    Letting this here, if it can stir up some ideas.

    Yeah, it's what I mean that could be one of the issues. I am uploading a video to see if the behavior you talk about is the one I will be inducing.
     
    Last edited: Jan 16, 2021
  11. Yzangard

    Yzangard Registered

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    This leads to another interesting topic: what reliable cues do we have when we finally drive?

    Sound? No, not really...how can we tell the difference between a tire squealing and a tire slipping? Not really clear, not precise, not obvious...

    The FFB? At best it will be able to confirm but it's difficult to tell us exactly what's going on, there's a zone in the grip of the car that causes a weaker FFB, yet we still have a lot of grip at this level and anyway, not the sharpest or most reliable either.

    There is finally our sight...there, it's sharp, reliable and instantaneous...not for nothing that you need to perfectly adjust your FOV for that matter.
     
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  12. Yzangard

    Yzangard Registered

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    Sorry but where is the problem actually ?

    This guy is a total noob that is failing hard time making his point.
     
    Last edited: Jan 15, 2021
  13. Andrew Hollom

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    The driven wheels don't need a high lateral load to move laterally when they're spinning.
     
  14. Nieubermesch

    Nieubermesch Registered

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    Here it is the video. Do you think some of my driving is resemblant of your own? I think the car is allowed to rotate a bit more than it should when it should be sliding more, on some instances. Altough, as I said, there are points where I will lose the car no matter the input I tried.

    The way those cars are sliding isn't really what I was really doing, they look quite dangerous and are great saves, it isn't the same as what I did to the LMP3 car. I also wouldn't expect that an F1 car could do that, as I can't do it with any one of them in Rfactor2, only with historic ones, for obvious reasons..
     
    Last edited: Jan 16, 2021
  15. Yzangard

    Yzangard Registered

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    ACC and iRacing have similar punishing traits of driving ? Seriously ?

    Nope, not even close, ACC is WAAAAYYYY more forgiving than iRacing. iRacing will instant punish you if you go even a tiny bit over the limit while ACC will...act exactly like rFactor 2 actually, I've seen no difference.
     
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  16. Nieubermesch

    Nieubermesch Registered

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    That's not true. There are subtle and some other accentuated differences on grip dynamics between ACC and Rfactor2. That said, I also think it's going to far to say ACC is closer to Iracing. Altough I think they are when we talk about WHEN car will enter a unstable slide.
     
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  17. Yzangard

    Yzangard Registered

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    There are maybe some subtle differences (very hard to say, would need to have the exact same situation to compare) but they are pretty damn close. I've never seen any "accentuated" difference between them but did I saw everything ? Surely not.

    But iRacing is clearly over slippery to the last degree which is not the case in ACC or rFactor 2. I have thousands of laps made in each of these simulations with all telemetry kept (well, ACC telemetry is thin, to say the least, not a lot of channels to play with) and I can assure you all 3 simulations are pretty close until the "loss of grip behavior" occurs...iRacing is way too much punishing, it is unrealistic, clearly, no need to "prove" it, just common sense is enough. I know I said that to prove many points in this thread we need actually data but :

    1) grip data aren't published with iRacing, so you just can't use them
    2) I don't need any scientific proof to know that a car can't slide for 50m at 30 km/h when sliding on dry surface, especially with extremely high performance tires like F1 cars have...yet, I have videos proving this happens in iRacing
    3) I don't need any scientific proof to know that slightly touching a car when driving should not make it spin like crazy 100% of the time, no matter the angle, the speed or steering position...(this doesn't happen with new damage model cars, as if something is "fixed" with this NDM...will have to wait for GTs to get it to be sure but GT4 can actually "fight" without instant spin all the time).
     
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  18. Nieubermesch

    Nieubermesch Registered

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    Actually looks pretty close to Rfactor 2 behavior. A nice video, because normally we only see drivers driving them smoothly.



    Then you look at this at it doesn't seem that far off, but there is more leeway on Rfactor2, it looks like to me
     
    Last edited: Jan 16, 2021
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  19. Nieubermesch

    Nieubermesch Registered

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    Don't get me wrong, I agree with everything you've just said.
     
  20. mantasisg

    mantasisg Registered

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    Damn.... look at this. Not often we can see GT3 cars or many other modern racecars man-handled like that. Driver should be careful because he might end up "cancelled" by vehicle rights activists for "toxic" driving.

    Just look how sharp, quick and precise are these steering motions, thats because thats how the car is, thats how the tires are.
     
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