Poll: Is this driving realistic?

Discussion in 'General Discussion' started by Nieubermesch, Jan 23, 2021.

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Is this driving realistic?

  1. Yes

    31.6%
  2. No

    68.4%
  1. BT7 Driver

    BT7 Driver Registered

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    Edit - I need an editor or stronger coffee at that time in the morning - sloppy units error corrected - m/s^2 not Newtons!

    I don't think you need to be overly worried @Lazza - I think you almost certainly have the conversion right and it is easily checked.

    The other point to be made is the combination of the words Vertical (direction) and G (unit). Vertical G is then so easy to misread as a force, but it's actually an acceleration, expressed in G units rather than m/s^2. That may have been part of the train of thought at one point in time.

    @Yzangard - you reached the goal, establishing the car mass (F = ma), but I thought it would be useful to provide some clarifications around the physics as some of the posts may have generated confusion.

    Like Lazza, I contribute to these threads to encourage the better informed posts, respond to those less well informed and hopefully provide useful information and resources for those who are interested.

    I saw a reference to slip angles in iRacing greater than 1 degree leading to instant wall contact. I have no idea how that conclusion was reached, but it certainly doesn't align with my telemetry work with the sim. Part of the problem is that many iRacing subscribers don't understand what slip angles are (often confusing them with car yaw angle, for example) or how to derive slip angle estimates in a sim that doesn't report them directly. I do tend toward the view that the iRacing has a countersteer response problem, in some cars at least, but that's the subject of ongoing debate over there.
     
    Last edited: Feb 4, 2021
  2. Lazza

    Lazza Registered

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    @BT7 Driver you beat me to posting, so just for clarity: yes, I'm just using the local car Y acceleration to arrive at vertical G. The fact I'm using that and making it zero based didn't bother me; what bothers me (slightly) is that I forgot that's how I was doing it :D
     
  3. BT7 Driver

    BT7 Driver Registered

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    Cool, thanks for confirming. Don't change the base - you have it correct.
     
  4. Yzangard

    Yzangard Registered

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    It was my "mistake" actually, I should have explained why not being 1 caused an issue with what I was searching and indeed, it may lead others to think that gravity is wrong in the game.

    As reported a bit earlier, what @Lazza plugin is reporting is acceleration so on a horizontal plane, vertical acceleration is null, so 0 is the right value to report.

    Just to let others be aware of that, when we are checking for vertical load on tires, gravity exists and counts but it is not up to MOTEC to do the calculus for us. If there are inconsistencies, maybe it is just our own created math channel in MOTEC that didn't took everything into account, not the game itself.

    Sorry @Lazza , I should have been clearer since the beginning.
     
  5. Lazza

    Lazza Registered

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    Out of interest, and this is more physics related than realistic driving, but I suspected the "detached doesn't mean detached" thing might have been an rF2 bug. So I did some testing in rF1, found a good repeatable test in the Howston at Essington (out of the pits, 3rd gear, on the limiter: understeer off T2).

    Increased the rear ARB base value 100-fold (diameter based rather than spring), and the same "detached" now oversteers in the same scenario.

    The rF1 hdv comment on detaching ARBs is even clearer ("AllowNoAntiSway=1 // Whether first setting gets overridden to mean no antisway bar"), so it seems like a long long long-standing bug. Through years of modding I never thought to check it (and generally the lowest ARB settings are close enough that the difference isn't major).

    It's possible I tested it badly, of course.
     
    Last edited: Feb 4, 2021

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