Lets talk about the MERC GT3 FFB?

Discussion in 'General Discussion' started by LokiD, Nov 30, 2017.

  1. d0nd33

    d0nd33 Registered

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    Again, it looks like the FFB is working as intended: there is a fall in torque at the steering shaft. Who worked on the car's physics may give an answer to this matter.
    What worries me the most is the very high amplitude of high frequency oscillation, that sounds worse than the lower median torque.
     
    Last edited: Jan 3, 2019
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  2. vittorio

    vittorio Registered

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    Sorry I don't have any knowledge to give advise. I was lucky to trust one guy in USA which I thought had great ideas and klowledge - like replacing dying and cheap consumer Fanatec motors by robust industrial motors including motor inside-out cooling by an air pump. I was lucky to trust the right person because everything he promised indeed works amazingly. But upgrade cost me €500. So in the end - by total cost of ownership - i could have bought me a high end DD wheel too (like OSW), which even didn't existed at this time (only $5000 bodnar wheel).
     
    Last edited: Jan 4, 2019
  3. tlsmikey

    tlsmikey Registered

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    If you took that chart with the merc ffb and overlayed the corvette gt3 you’d see how drastically off the merc is. I don’t know if it’s a physics limitation of the tire model or if something is just modeled wrong but there shouldn’t be that type of fall off. And if there is it should at least be consistent.
     
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  4. davehenrie

    davehenrie Registered

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    I would like to see the graphs of the Calloway and Bentley compared to the Merc. Somewhat similar cars that should have somewhat similar printouts if everything is working correctly on all the cars.
     
  5. RockShark

    RockShark Registered

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    Merc and Calloway FFB overlaid

    ffb.JPG
     
  6. mantasisg

    mantasisg Registered

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    I am not used to telemetry. But maybe that could be result of bumps and kerbs, combined with stiffness of suspension and maybe something like scrub radius ?
     
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  7. Christos Segkounas

    Christos Segkounas Registered

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    I thought people said the AMG FFB is reversed, shouldn't work like that, car's possessed etc
    What I see on this graph is that the AMG's FFB is just lighter at high steering angles...
     
  8. Will Mazeo

    Will Mazeo Registered

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    Never seen anyone saying it's reversed, what people talked about is taht it goes weaker (almost off in my DFGT) after some degree of rotation (and no, it's not understeer), but this is only the ffb resistance, the bumps and curbs work at normal strenght so it gives a very weird feeling, none of the other cars do this.
     
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  9. d0nd33

    d0nd33 Registered

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    You're right, but we can see that there's a lot of noise even when the wheel is turned and torque falls. I guess this is the same effect @SPASKIS noticed one year ago.

    @avenger82 Data Rate in DAMPlugin.ini should be set at 5 to log FFB Output and Steering Shaft Torque at 100Hz, otherwise you'll have a smoother line.
     
    Last edited: Jan 4, 2019
  10. avenger82

    avenger82 Registered

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    OK I though default is enough. Will post more telemetry for Corvette and AMG GT3 on Road Atlanta, because I will the issue is very pronounced in first few corners with Merc.
     
  11. Korva7

    Korva7 Registered

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    I'm pretty sure that the people who have done the physics have noticed the difference in ffb compared to other gt3s, and if there was good reason to think that the ffb is not right, they would have done something to make it more similar to other gt3s before release or in some of the updates these cars has had. In assetto corsa there seems to be separate option for stronger pneumatic trail drop off (Enhanced understeer effect) but i prefer that the amount of that effect is based on the steering geometry of the car.
     
  12. patchedupdemon

    patchedupdemon Registered

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    Don’t give S397 too much credit, they are used to releasing unfinished products and not fixing them, the original gt3 pack still had issues unfixed
     
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  13. vittorio

    vittorio Registered

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    Too much credit? Assuming S397 drove and tested their cars and beta testers did too? Wrong FFB isn't something you don't notice like some GFX glitches. The only thing i can imagine is that FFB for AMG doesn't feel well on some wheels (and maybe even only at some settings). As I already said, for me it is the best GT3 because of FFB. Another thing I can imagine is, that they too felt that FFB is different, looked at physics data and concluded it is correct. (but if that is the case why S397 didn't answer already)

    EDIT: I think what is most likely is that S397 knew after tests that FFB is different but it is correct, and probably even know it is difficult for some wheels (as I still think low end wheels have problems after discussions at discord). But artificially change their model to get wrong but more common FFB was not an option. Physics calculated that behaviour.
     
    Last edited: Jan 4, 2019
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  14. Andregee

    Andregee Registered

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    The ffb isn´t broken. Is not more than less the result of the steering force calculation with low caster settings. What Studio 397 could do would be to use a different calculation method with negative aspects to other cars so that we can´t feel understeer with other cars no more, to integrate a slider with which we change the calculation, or to make the caster changeable in the setup.
     
  15. patchedupdemon

    patchedupdemon Registered

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    this car is in most sims and feels the same in all but one, rf2, there is no reason for it to feel vastly different from any other rwd front engined car reguarding ffb, unless people are saying all the other sims have it wrong and rf2 is the only one to have it correct.
    Rf2 and car modelling along with its physics has a lot to improve on, I mean a lot, the only saving grace is the tyre model
     
  16. vittorio

    vittorio Registered

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    what "sims" are these where you think AMG GT3 is modeled correctly?
     
  17. stonec

    stonec Registered

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    Most other sims are not calculating FFB 100% from raw physics output, they use effect-based FFB, which makes all cars feel similar. Different FFB of this car could well be a result of different suspension geometry. If S397 got the data from the manufacturer and the end result of FFB is this, what are they supposed to do?
     
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  18. mantasisg

    mantasisg Registered

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    It is best when there are as little as possible "ffb calculations" and it comes from physics as purely as possible.

    @patchedupdemon there actually are some reasons, possible explanations. I think you are underrating S397, rF2 physics models wouldn't automatically make cars great. Though I dislike few things myself about their physics, which I think ISI did better, but I think ISI also overdone few things, probably... so it is 50/50.
     
  19. patchedupdemon

    patchedupdemon Registered

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    They are supposed to reply to this long thread explaining why it feels as it does, saying nothing gives the appearance of just burying heads in sand, why not put it to bed once and for all.
    Steering geometry doesn’t really differ that much between these cars, it would have to be vastly different for it to give such polar opposites in ffb feel.
    The merc feels like driving any front wheel drive car on ice, as soon as you turn the wheel, no matter the speed, all feeling just goes.
    Either it’s a mistake in how they created the cars steering geometry, or it’s a conflict with some of our wheels
    Either way they should show some interest
     
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  20. Korva7

    Korva7 Registered

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    @mantasisg think it's mostly the same guys working on the physics engine now under s397 as it was on isi's time. I could be wrong though.
     

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