Does rF2 implement chassis-flex or semi chassis-flex?

Discussion in 'General Discussion' started by Joe, Sep 2, 2015.

  1. Joe

    Joe Registered

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    I seem to recall one of the replies from rF2 developer implied that the chassis-flex was implemented. Just want to confirm.
    The reason I ask is recently I tried AC cars, which seem improved a lot. But, in terms of bump, bounce and shaking feel on motion rig, the rF2 is still more "realistic" than AC.
    This has been the case since AC came out first time. I wonder if the chassis-flex (or semi chassis-flex) indeed play the role here.
     
  2. GCCRacer

    GCCRacer Banned

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    Depending on mod, but yes it's supported and most mods these days have it.
     
  3. Joe

    Joe Registered

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    Only on mod car? not on rF2 native cars? thanks
     
  4. Maug

    Maug Registered

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    The term mod is used also for the original content.
     
  5. Joe

    Joe Registered

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    Thanks guys. I think this may explain why the rF2 cars feel far better than AC cars on the motion rig.
     
  6. Korva7

    Korva7 Registered

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    Possibly (propably) better suspension physics and tyre model play a role on that too.
     
  7. WiZPER

    WiZPER Member

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    The "flex" is in the physics only, but really advanced - there is no visual flex happening, just to be clear on this :)
     
  8. Joe

    Joe Registered

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    Yes, I meant to "physical" physics, not "Visual" physics. the AC car "Visual" physics is very good however:
     
  9. WiZPER

    WiZPER Member

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    But now you are showing a video of suspension movements, rf2 does this visually fine too - but chassis-flex is not visual in either sim to my knowledge, and I don't even know if AC physics account for it.

    Chassic-flex has an impact on the feel of the car, both in FFB and motion rigs because it allows for a different weight transfer even though you can't tell looking at the 3D model.
     
    Last edited by a moderator: Sep 3, 2015
  10. MikeeCZ

    MikeeCZ Registered

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    Well.. as far as i know AC doesnt have chassi flex at all. DOnt know what do you mean by chassi-flex/semi chassi flex but in rF2 majority of cars ISI and non ISI have chassi flex, some of the ISI cars are still being updated as far as i know tho.

    CHassi flex is not visual, but.. it actually sorta is. The visual position of your wheels is physically accurate (sometimes there is some graphical offset but still), the other parts of the car not so much, those are mostly just visuals. So i believe that you would be able to observe the chassi flex on tyres if you pay attention enough.

    There are not many limititations as to how to implemente the chassi flex, but the ISI cars use two physical bodies (front half of the car and rear half of the car) that are connected together with a very very stiff ball joint, the stiffness is according to the particular car twisting stiffness (as an example of by heart - koenigsegg One:1 has chassie flex stiffness of 92000N/mm, each car differs.)
    These two physical bodies than have all the respective suspension parts bolted to it.. so basicaly the suspensios is moving relative to each other as the two physical bodies twist and bend.
     
  11. David Wright

    David Wright Registered

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    Chassis flex won't affect the position of the tyres, except in extreme circumstances when/if the tyre leaves the road surface.

    Racing cars are normally stiff enough that chassis flex has very little effect. I'd suggest chassis flex is primarily of use for simulating karts.
     
  12. Miro

    Miro Registered

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    From my experience in rF2 it has quite a big impact on car behaviour in different situations such as braking, turning ,even accelerating, etc. and as well on the performance.
     
  13. Emery

    Emery Registered

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    Historic cars are also a primary use. Modern race cars are about 10x stiffer than '60s era. The importance of chassis stiffness became more apparent as tires got wider. For numbers, I know McLaren Mk 1b is twice as stiff as McLaren Mk 1a (late 1965, early 1966), but still significantly less than modern race cars. By the '70s, chassis stiffness was regularly designed in, though rules sometimes made it difficult to implement (e.g. SCCA club racing let you weld in a 6 point rollcage, but you couldn't use more than 6 points, so all the triangulation has to occur within the rollcage and you saw some creative use of spaceframe structures).
     
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  14. Spinelli

    Spinelli Banned

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    I don't agree because Formula 1 cars are some of the stiffest cars around and I often hear engineers saying they made stiffness improvements to the car from one year to the other.
     
  15. TechAde

    TechAde Registered

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    Very little effect, not no effect. F1 engineers chase every very very very little effect they can. :-D

    Sent from my SM-G900F using Tapatalk
     
  16. David Wright

    David Wright Registered

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    The effect of chassis flexing depends not only on chassis stiffness but suspension stiffness. The stiffer the suspension, the stiffer you need your chassis to be. Racing car suspension in the 60s was amazingly soft, and so the 60s chassis didn't have to be anything like as stiff as they need to be with modern stiff suspensions.

    Chassis stiffness was designed in to purpose built racing cars well before the 70s, though I agree the use of the roll cage to stiffen the chassis became common-place in the 70s.
     
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  17. DurgeDriven

    DurgeDriven Banned

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    How is that good visually !

    It is hardly moving , watch a real 60 F1 car

    Even GPL is closer to reality then that !





    Yes yes yes Monaco is bumpier yes and Monza has less movenment......... no matter the AC/Monza is ridiculous.

    P.S. watch the braking at Parabolica suspension does not even dip ! lol

    and 30mph you get suspension movenment in RF2 whilst braking ...omg
     
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  18. Joe

    Joe Registered

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    @DurgeDriven
    Interesting....,
    I checked youtube video of AC classic at Monaco, which suggests you are right (I hardly see suspension drop and rebound and bumping):



    Checked rF2 classic BT20 at both Monaco and Monza too, the rF2 suspension seems more realistic (in referenced to real life one). I am glad you posted the real-life video. This is pretty solid proof though:





    Thanks guys.
    take away from this thread is that the effect of chassis flex is too small to feel. Likely the better suspension, and other aspects modeling contribute to more realistic feel on rF2 than on AC.
     
    Last edited by a moderator: Sep 4, 2015
  19. DurgeDriven

    DurgeDriven Banned

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    Here is GPL

    Why didn't AC use that as a guide they would have been closer. hehehe ;)



    Slower then F3 that lap hehehe , with proper pace you would see more suspension movement
     
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  20. DurgeDriven

    DurgeDriven Banned

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    OT Point I was making it is the combination of all ISI features that gel together so well makes the complete package.


    Without real road, great bump mapping, tyres and physics ( kinda sounds like AC or pCars...lool ) then chassis flex would just be another thing if you get my meaning.


    When Historics are done I expect F3 will stand up on rear tyre a lil' more at Parabolica and want to push push push ! hehehe

    I want Flex ! ............the wait is getting to me. p
     

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