AMS2 vs AMS1 Physics

Discussion in 'General Discussion' started by JS1, Aug 2, 2020.

  1. CrimsonEminence

    CrimsonEminence Custom Title Staff Member AMS2 Club Member

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    The car on the video has a broken differential, why it's behaving very odd, washing out every corner, but suddenly becomes nervous and kicky with the rear.

    I was just checking, if it's washing out due to entry follow-up or throttle/car load induced understeer for you.

    Maybe it's really the best, you might record a quick run.^^
     
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  2. BrunoB

    BrunoB TT mode tifosi BANNED

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    @Jugulador be aware I was not patronising or being sarcastic when I said installing a record prog just for recording this is not worth it.
    Because this issue is so tiny seen in relation to the extremely good general behaviour of this car.

    But my intuition and general knowledge of RL car physics tells me that in such corners where the load via the constant throttle pressure is higher on the rear tires - then it should be these and not the front tires that should give away.;)

    @CrimsonEminence haha you think so. But as said this will not be recorded By @BrunoB :D

    ByTheWay: I havent checked it but Im pretty sure that the ghost lap from my fastest lap on the LB Brands HatchGP does show this tiny slide. Hehe and how the driver is extremely good to correct it.:rolleyes:
     
    Last edited: Aug 6, 2020
  3. CrimsonEminence

    CrimsonEminence Custom Title Staff Member AMS2 Club Member

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    Tyres can just generate grip, if they get load, it's not working otherwise. Constant throttle pressure for turning is also highly diff dependent, weight transfer would more likely work against you and too much of it unloads the fronts -> fronts can't generate more grip -> aero and a bit more lifting might help you out. Maybe front tyres are unbalanced in bite, compared to the rears.
     
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  4. BrunoB

    BrunoB TT mode tifosi BANNED

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    OK I understand what you are saying - but be aware that "constant throttle" in the corners described is actually some slight acceleration to counterweight both simulated drag and rubbing/drifting energy wasted with friction against the tarmac.
    So the diff will be in more or less constant power state (until I lift slightly to save the understeer ups);)
     
  5. CrimsonEminence

    CrimsonEminence Custom Title Staff Member AMS2 Club Member

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    Yes and the front tyres will be more or less in less load state.
    I have no clue, how much is car, setup, tyre and driving related, but it's not necessarily unrealistic, that you wash out at some point.

    With a Porsche cup, this for example is the same in R3E and rF2...you often gain time by actually coasting through the apex, applying half throttle or a tiny bit more and open it up gradually, after it "settles" in. This is, because the Porsche Cup lifts it front extremely strong due to rear engine and the big ol' wang at the back that at one way gives stability, but on the other side actually lifts the front a bit. So consistent weight transfer of load to the fronts is required there.
     
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  6. SlowPoke80

    SlowPoke80 Active Member

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    This is exactly what Niels was talking about when he said he prefers empirical tire models over physical ones. It would be so much easier for you to fix things with the AMS1-style empirical type. Instead you now have a needlessly complicated one, which will only yield bad results, because it isn't possible for anyone to attain the absolute perfection needed to get it working realistically.

    I don't know how much control they've given you over modifying the ME, but if it's possible to replace the tire model completely, then you should try it. I know it would be a lot of work, but at least you could get realistically handling cars. The alternative is to throw the same amount of work into the ****ty SETA tire model, and still end up with ****ty results.
     
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  7. tlsmikey

    tlsmikey Active Member AMS2 Club Member

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    I don't think the SETA models are bad, but you're 100% right they are very complicated. This is why ACC is only doing two tires (GT3 and GT4....well, maybe a cup tire but i've not heard confirmation of that). I think iRacing has a SETA model or something similar as well as they roll out tire updates on a per car basis and have lamented over how complicated the model is.

    My point is that it is possible to get some decent function out of these models, but the amount of cars that Reiza had taken on makes me concerned if they'll get all of these working properly in the long run.
     
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  8. Renato Simioni

    Renato Simioni Administrator Staff Member

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    Nah -happier with the results we´ve got already, happy with the amount of adjustability it offers - it is not as inflexible like other physical tyre models, actually quite easy to work with if not quite like the old model. It´s the price of progress, and it offers us potential to improve relative to a tech that we had already pretty much maxed out.

    Everyone is of course entitled to their opinion, and to look elsewhere if they´re not hooking up with it as it is now - maybe revisit lt later to see it´s progressed more to your liking. Ultimately opinions can and do vary, and people do seem to have some very strong, often contradicting convictions about how sim physics should handle like - we don´t expect to cater to them all :)
     
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  9. David Wright

    David Wright Active Member AMS2 Club Member

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    Kunos are using a modified version of their AC tyre physics for ACC which is a brush model I believe. Its not a physical type tyre model.
     
  10. SlowPoke80

    SlowPoke80 Active Member

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    The ACC tire model is quite nice now that they've updated it to have five or six sections per contact patch. It used to just be a single point for each tire, like in AC. That lead to horrible curb physics. The old AC is still fine if one avoids tracks with raised curbs and lots of bumps.
     
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  11. Jugulador

    Jugulador Well-Known Member

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    If you apply constant throttle in any mid/slow corner the car will have a tendency to naturally loose speed, and them the balance inevitably will change with the same happening with car attitude.



    Try to see what is happening with the car on almost every corner. The driver keeps the brakes until near the apex to induce the attack angle farther than the corner radius because he knows that right after go on throttle the weight will shift (you can see it happening, beside this car having a very rigid suspensions) making the car gradually point to the outside EVEN IF HE START TO TURN THE STEERING WHEEL MORE AND MORE AFTER THE APEX on corner #2, the tight one (you used it as an example... and the real car behaves as at most AMS2 cars at the same corner). At every corner he is working different levels on each pedal and doing a lot of steering corrections and you can see that it is to deal with this weight shifting tendency.
     
  12. BrunoB

    BrunoB TT mode tifosi BANNED

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    I wont go into car behaviour in mid/slow corners and what happens when you brake or modulate the throttle up or down - as in the video.
    My friendly critique of this tiny issue is as I have pinpointed from the beginning only something that I consider wrong behaviour in high speed and high pressure "pirouette" corners like the two I pointed out on Brands Hatch GP.
    And furthermore Im talking about the high powered F-Reiza car.
    Eventhough I probably later will check out if the other of Reizas semi-modern formula cars exebit the same anomali in such situations.:cool:

    ByTheWay: But even before I have checked it out I would be pretty surprised if its only the F-Reiza that has this "infection" - because I consider it as probably part of the general new tire model.;)
     
  13. Jugulador

    Jugulador Well-Known Member

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    You said Druids and Surtees corners, that are slow corners (and I used the Druids as an example).

    The Surtees is even more complicated, because it have two different radius, in an elevation change, and it get tighter at this end. You can't "constant throttle" none of those.

    [​IMG]
    Just for reference, because you can be mistaking the corner names.
     
  14. SuperMonaco_GP

    SuperMonaco_GP Active Member

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    the thing of physics/tyre model of ams2 that I really don't like and detracts a lot from the overall experience is how weirdly a lot of cars, especially classic 80/90s F1 tends to do lateral slides "in place", meaning that the auto-center force on the wheel after that happens makes it feel quite broken imho.
    I never been into an 80s or 90s F1 car, but given how those types of cars have always been represented among all other current sims, makes the ams2 versions very weird to drive.

    another thing that I don't understand is this : I play with a Simucube2 DD wheel, therefore I only use total gain ffb and no LFB or effects, just like any other sim. but in ams2 even with just total gain you get a constant "scrub" feel and overexagerated road noise that detracts a huge amount of actual valuable info you get through ffb. so, I get that those are physics based effects, but if so why can't we have the chance to implement them with the "effects" slider and leave them out from the pure gain? I just want to feel tyre load and chassis movements through the ffb, because with a DD wheel there is absolutely no need to activate any kind of effect thanks to the motor torque and fidelity that manages to make you feel such things anyway.
    so, at the current state of ams2 ffb, I think it has a huge potential but there is too much unnecessary noise happening when driving, like I said at least on DD wheels like mine.
     
  15. BrunoB

    BrunoB TT mode tifosi BANNED

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    Hehe you dont know what I can`t ;)
    But I agree partly that Druids is not exactly a high speed corner but I included this corner because the same sudden understeer happens in that corner as in the high speed Surtes.
    Because its the Surtees corner where this anomali shows up most.:eek:
    I take it with completely full throttle !! - but using the RPM limiter in a slightly too low gear as "constant throttle" controller.
    And I havent had time to check the km/h :D but at least for me Surtees is a pretty high speed and specially high lateral forces corner.

    ByTheWay: If you still think Surtees is such a slow corner as you are saying then try to follow BrunoB´s ghost on the LB through that corner - and then come back and tell me that its still a slow corner :D
     
  16. Jugulador

    Jugulador Well-Known Member

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    Challenge accepted:) What car are you using in your BH record?

    Anyway, in Surtees it happen because of the corner shape... is a very hard corner to master in any sim (I never drove on the RL place). At the video I've posted, both of the corners demanded some technique.
     
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  17. BrunoB

    BrunoB TT mode tifosi BANNED

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    Excited that you accepted my little challenge (thumbs up :D)
    Which car you ask?:eek:
    Come on my good man - I have only talked about the very good simulated Formula Reiza the whole time from my 1st post.:confused:

    ByTheWay: But I have to warn you - this car is BrunoB´s speciality. And eventhough Im not quite topping the LB then Im quite unable to understand how the 3 drivers above me does manages to drive even faster.They must be genuine aliens:confused:
     
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  18. Jugulador

    Jugulador Well-Known Member

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    F-Reiza it will be:cool:
     
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  19. BrunoB

    BrunoB TT mode tifosi BANNED

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    Hey @Jug I just checked the LB.
    What is your LB name?
    You are not the GearNazi guy - right?:whistle:

    BrandsHatch_Page2_LB.png
     
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  20. Jugulador

    Jugulador Well-Known Member

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    Im not Mr. Gear nor Sir David Phillip Cooper I... it's Jugulador... will put some time on this board after the new patch, that is 10 hours late. C'mon Reiza, don't be shy:D
     

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