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Discussion in 'Automobilista 2 - General Discussion' started by BiggieShmeezh, Dec 7, 2020.

  1. BiggieShmeezh

    BiggieShmeezh New Member

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    Why the hell do cars still bounce around like im driving on a kids bouncy castle? Its mainly an issue with the F1 cars and I can't stand driving them in this game as they bounce around so much that it makes it hard to see anything and can cause me to lose grip in some corners. Are there any plans to fix this because it seems like it never will be fixed.
     
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  2. BrunoB

    BrunoB TT mode tifosi BANNED

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    It has been reported several times - and Reiza has (somewhat ;) ) acknowledged it because they have tried to sidestep this problem by introducing a few extra damping lines in the camera menu.
    As I have mentioned before my guess is that this "bug" is something deep in the Madness engine that they cannot control. So they can only try to sidestep it.

    ByTheWay: Your only chance to avoid it is to choose another track. Because eventhough you cant get completely rid of it it is also trackdependent.:rolleyes:
     
  3. SaxOhare

    SaxOhare Well-Known Member AMS2 Club Member

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    I don't mind it at all, at contrary I love it makes me feel like I'm in the car, A car has to shake,The car is shaking around me but still i have a clear view on the road (Head-Movement 100 Head speed off ,no legacy and G-Force at 0)
    I meanly drive formula Vintage Retro or Classic
    Only the Formula-Reiza, the Formula-Ultimate and perhaps one of the other modern F-cars have a annoying wobble while standing still and in slow corners which goes away on higher speeds.
     
  4. Marc Collins

    Marc Collins Internal Tester AMS2 Club Member

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    Use the settings from post above this one and see what happens...
     
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  5. steelreserv

    steelreserv Well-Known Member Staff Member AMS2 Club Member

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    The dampers for many cars in the game are too soft for even the min spring rate, especially the rear dampers. Any camera adjustments are just a visual fix, but it does not fix the root cause.

    Below is a telemetry based "damper histogram" for the Porsche GT3. It tracks the "activity" of the dampers.

    Ideally, you would want a sharp conical-like shaped histogram with zero node peak at around 12-20%, depending on the bumpiness of the track. Not a "mound".

    Here you can see the zero node for the RL and RR are peaked at ~7%. (The fronts I softened to match because you want balance between the dampers.)

    The damper speeds left and right of the zero node (represented in mm/s) indicate rebound and bump respectively with HS damping >30-40mm/s and slow damping at <30-40mm/s (where the peak at the zero node should peak).

    The more your dampers are working, the more the zero node drops and the mound shape appears. This means the dampers are not keeping up with spring oscillations, which leads too...

    B O U N C E
    Capture.PNG

    [​IMG]

    The attached is a more ideal representation of how a proper histogram should appear. This is the Cadillac GT3 for PC2, therefore the issue is NOT the madness engine as suggested previously.

    It is a matter of the springs to stiff and the dampers too soft. Even at Min/Max settings.

    [​IMG]
     

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    Last edited: Dec 8, 2020
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  6. BiggieShmeezh

    BiggieShmeezh New Member

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    Wow this is a very good explaination. So it seems the hardness of the springs or dampers (or both) arent working very well together and causing the bouncing?
     
  7. steelreserv

    steelreserv Well-Known Member Staff Member AMS2 Club Member

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    Yeah. The histograms show the dampers generally are moving to much. They require several cycles (up and down) to stop the springs, which we feel as bounce.

    Dampers that are too stiff compared to the springs, stop the oscillations too much and the wheels cant keep up with the tarmac beneath them.
     
  8. Avoletta1977

    Avoletta1977 Well-Known Member AMS2 Club Member

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    I agree with you.
    By looking at the 911 suspensions values and applying realistics motion ratios (0.8-0.9) the damping ratio is around 0.4-0.5 (too low for a stiff race car); 0.6-0.7 would be a more reasonable value.
    Adding bumpstop into the equation would lead to even lower values and IMHO mostly explains the oscillation in some of the affected cars.

    P.S.
    Of course the tire stiffness may play a big role here, so it's certainly something to be looked at as well (very complex because probably vertical response is linked to several other characteristics and adjusting one may screw everything else), but the upper body damping is quite strange just by the raw presented numbers and adjusting it shouldn't be so complex or time consuming.
     
    Last edited: Dec 9, 2020
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  9. azaris

    azaris Well-Known Member AMS2 Club Member

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    I noticed the same thing a few weeks ago when the Porsches first came out. The conclusion was the same: the suspension velocity histograms are too flat, indicating insufficient high-speed damping. I redid the experiment after the helper springs got fixed and, to my surprise, noticed very little difference in the histograms, even though the car clearly felt better. I figured that maybe the histograms don't tell the whole story because there was a bug, or maybe I misunderstood something, and didn't mention it here.

    I also compared vs. other sims - in R3E the suspension velocity histograms look more or less as they should (which is what I would expect from a sim developed by a suspension manufacturer), while they appear overdamped in AC (corresponding to my feeling that cars in AC feel more stable and glued to the road than in other sims).

    More worryingly, I also noticed the same feature in all other cars I tested, even ones where there is no bouncing feeling from the FFB. Here is the same plot for the Copa Uno, which doesn't bounce in a noticeable way. So now I'm left wondering if there really is a consistent issue in the way dampers are handled or whether it's some kind of telemetry bug?
     

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  10. Jens E.

    Jens E. Member

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    well telemetry should show the "real deal" underneath.
    you even can feel that the car is unable to brake and cornering (heavy understeer!) with this bouncing.
     
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  11. steelreserv

    steelreserv Well-Known Member Staff Member AMS2 Club Member

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    Exactly. The damper transition speeds are missing as a setup option. They were in PC2 and atter few moments using a spreadsheet you could have decent damper settings, Another problem is the cars dont have enough spring options. In PC2 the Porsche GT3’s softest spring setting was 90N/mm, here is in the 200’s. I could be a coding issue as well. I never encountered the bumpstop issue because I tuned it immediately which solved the problem in a significant way and never noticed a change after the first update.

    The stiffened tire walls worsened the problem again. Especially when using curbs. They make cars waaay too unstable now and the car cant recover due to insufficient damping.
     
  12. steelreserv

    steelreserv Well-Known Member Staff Member AMS2 Club Member

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    Packers main job is for pitch control and bottom out prevention. They are more vital for aero cars. Most of the the issue here is straights and cornering, especially straights though. With such low transition speeds I can only wonder if the HS dampers are taking over for the LS dampers job sometimes too.
     
  13. Gordie

    Gordie Active Member

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    Some great explanations and theories here, let's hope this gets looked at as a matter of urgency.
    Having a hard time enjoying this sim atm because of this.
     
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  14. Avoletta1977

    Avoletta1977 Well-Known Member AMS2 Club Member

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    By digging into the data of other sims, the damping ratios for GT3s are much, much higher.
    Even by comparing them with road legal units for conventional cars they seem not properly tuned for the very high spring stiffness values implemented (mainly for slow damping).
     
    Last edited: Dec 8, 2020
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  15. Marc Collins

    Marc Collins Internal Tester AMS2 Club Member

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    Agreed. Contributors, please put the most important evidence in the main physics feedback forum.
     
  16. VFX Pro

    VFX Pro Well-Known Member AMS2 Club Member

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    Are we basically saying that the cars (mainly certain open wheelers) just need a more realistic default setup (springs/dampers) to fix the extra bounciness (which is often perceived as a camera problem)?
     
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  17. Avoletta1977

    Avoletta1977 Well-Known Member AMS2 Club Member

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    We don't know for sure but several setups are odd and they won't certainly help at solving the issue.
     
  18. steelreserv

    steelreserv Well-Known Member Staff Member AMS2 Club Member

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    Well, we should make sure not to confuse some of the other bugs with the formula cars that have been discussed before. The "bounce" or shake when they come to a quick stop, for example, may be unrelated.

    Unfortunately, I haven't driven everything, so I can't speak for the game as a whole, but it appears that it is a problem with several classes, open wheel and tin top.

    But yes. The things that we can ask for and anticipate a fix for in the future are:
    -More setup options (stiffer and softer) for HS and LS dampers
    -More setup options (softer generally) for Springs.
    -Player adjustable damper transition speeds or raising the default to a more realistic range. From 35-40mm/s (as it is now) to around 50-70mm/s.
     
    Last edited: Dec 8, 2020
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  19. Jens E.

    Jens E. Member

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    i only need a car that drives with the standard setup and im fine...
    options (if the car has the option to change them, are welcome for the hardcore setup changing freaks) ;)
     
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  20. steelreserv

    steelreserv Well-Known Member Staff Member AMS2 Club Member

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    I'm in that category, its part of what a "sim" is isn't it? :D
     
    Last edited: Dec 9, 2020
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