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To Reiza: What physics do you actually want?

Discussion in 'Automobilista 2 - General Discussion' started by Richard Wilks, Jan 3, 2023.

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  1. steelreserv

    steelreserv Well-Known Member Staff Member AMS2 Club Member

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    I've watched that video 100 times before and many others and at no point does it suggest that the clutch packs are in a constant state of slip. Of course the LSD slips. Its designed to control the slip. But by doing so, at times, it also locks the clutches packs when wheel slip is detected.

    The "sticky diff fix" was primarily oriented around the physics of a clutch in the "stick to slip" state. Stick means locked.

    And like I said before, its the margins where the LSD resists the slip and keeps the diff locked. That's its purpose.
     
  2. steelreserv

    steelreserv Well-Known Member Staff Member AMS2 Club Member

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    Simple experiement that is safe to conduct at home.

    Put the palms of your hands together lightly and make circles. Then increase the pressure of your palms together. That's how a clutch works.

    As an extra bonus, put you palms together and apply moderate pressure so that they constantly slip. The heat you feel is another reason why your suggestion doesn't hold it weight.
     
  3. Richard Wilks

    Richard Wilks Active Member

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    So basically you are admitting your LSD is a locker, and binds the two wheels together mid corner. Do you confirm this? Do you know thats what the physics are doing? OR is that only your interpretation from the graphics?

    The clutches are in a constant state of slip when wheel speed is different. The bigger this difference, the more torque is transfered. There could be extreme situations where 100% torque transfer could be achieved, but this is undesirable for the reasons i outlined and others more.

    I dont understand whats so hard on this. The spool or weld differential behaviour is well documented. And the last thing you want in a car is to go from one state to the other. Again, thats why detroit lockers are not a thing anymore.
     
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  4. Richard Wilks

    Richard Wilks Active Member

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    You just said above that the diff is always locked and it opens when you turn into a corner. Now you are telling me the opposite. So what is it?

    I think you are more confused than you think.
     
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  5. Nolive721

    Nolive721 Active Member

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    oh boy:whistle:I guess you just prove my point so thank you and lets move on:rolleyes:
     
  6. Richard Wilks

    Richard Wilks Active Member

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    "
    What is limited-slip differential (LSD)?
    By shifting torque between the driven wheels, a limited-slip differential (abbreviated as LSD) allows for faster cornering. This allows the car to make the most of its engine’s output by reducing wheelspin and maximizing traction. It is a type of differential that allows its two output shafts to rotate at different speeds but limits the maximum difference between the two shafts."

    https://studentlesson.com/definitio...rential/#Types_of_a_limited-slip_differential

    Again:

    It is a type of differential that allows its two output shafts to rotate at different speeds but limits the maximum difference between the two shafts.
     
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  7. steelreserv

    steelreserv Well-Known Member Staff Member AMS2 Club Member

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    I can take a look at it. TC has been a hot topic for a while, so it won’t get overlooked.
     
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  8. Dusty926

    Dusty926 Member

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    It disturbs me that more people have not chipped in to say this yet; Going back to PC2 is like going back to a mobile flight game after playing X-Plane. It drives...kinda like cars do, but it feels like garbage, nothing has any discernable weight but instead a constant, muddy roll that makes it extremely difficult to gauge how the car's behaving from the cockpit. It feels like complete garbage, and doesn't drive like any cars that I could think of.

    The Formula Vintage equivalents in PC2 especially feel absolutely wretched compared to every other sim you could drive. People in this thread are very quick to throw around faux-experience and technical semantics, but I can't take any of it in good faith as a layman when they hype up something that truly, drives barely any better than Forza Motorsport 7
     
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  9. Richard Wilks

    Richard Wilks Active Member

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    I dont see anybody hyping up anything, besides the specific combo i mentioned.

    The formula vintage in PCars2 was decent with historic/vintage tires, but nothing special. With the normal tires it was not good, because those had way too much grip for the car in question. There were other problems, but i could make the lotus 72 run very decent for example just with some setup tweaks.

    The group Cs with the same historic/comp tires were very good, certainly better than the ones in AMS2.

    Too bad very few people picked these optional tires from the setup menu, they transformed some cars.
     
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  10. steelreserv

    steelreserv Well-Known Member Staff Member AMS2 Club Member

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    Finish that quote bud.

    “ it is also known as self-locking differential or differential lockout.”

    Thats all taken from an introductory paragraph about the function of several types of LSD anyway.

    The relevant LSD here is a clutch plate LSD.
     
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  11. Richard Wilks

    Richard Wilks Active Member

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    Look, this is going around in circles. You obviously believe that a race car, or any car for that matter, should lock its wheels instantly as soon as it gets any slip (or in a straight line too apparently).

    All the sources i get say that they limit shaft speed difference, DESPITE THEIR NAME.

    Locking the shaft mid corner is a highly undesirable effect that existed with detroit lockers and ratchets, and was put into history for exactly that, being undesirable.

    Now if indeed the game is doing what you say, locking the wheels solid mid corner, part of the problem is already explained, you are turning cars into drift diff welded machines as soon as any wheel speed difference is created.

    Then we wonder why the rear is stepping out imediatly...
     
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  12. Richard Wilks

    Richard Wilks Active Member

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    Futhermore:

    "
    What is a Detroit Locker?


    The Detroit Locker is an automatic locking differential. This means it is normally locked during straight-line driving and sends 100% of the available torque to both wheels equally. During turns and maneuvers, the internal components unlock to allow one wheel to spin faster or slower as necessary (free wheel)."

    So basically what you have been describing the cars have in AMS2 its this, at least in a straightline.
     
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  13. Richard Wilks

    Richard Wilks Active Member

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    More definitions:

    "
    What's the difference between a locker and limited slip?

    Lockers produce 100% lock-up where all the power is directed to both tires all the time when the unit is engaged. Lockers are tougher. Limited slips direct torque to both tires and when slippage occurs the unit directs torque to the tire with the best traction."
     
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  14. steelreserv

    steelreserv Well-Known Member Staff Member AMS2 Club Member

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    Lat g metrics are an expression of a car’s cornering capabilities. Not vehicle dynamics.
     
  15. steelreserv

    steelreserv Well-Known Member Staff Member AMS2 Club Member

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    Why do you keep bringing up a locker. Its for rock climbing.

    I never suggested clutch lsd’s never slip. They always slip.

    You’re the one claiming the clutches never have enough pressure to lock the housing to axle, and thats false.
     
  16. BazzaLB

    BazzaLB Well-Known Member

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    I'm not sure if you two are just arguing semantics at this point. I was the guy who asked steel to make comment on this thread via the "latest release" thread. I was hoping for reasoned discourse that we could all learn from. It seems to me that with the LSD, because it is designed to "limit" the rotation difference between the left and right, if those differences are small enough to be below that limit, then for all intent and purpose the diff is "locked" from a logical perspective if not from a physical one, but once those differences become large enough to be over the limit of the LSD, then the diff is "unlocked". But I am not sure you two are actually disagreeing here necessarily but have instead become bogged down in semantics about defining the term "locked" which is confusing the discussion.

    Of course I could be wrong.. maybe you are both in complete disagreement. :)
     
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  17. Richard Wilks

    Richard Wilks Active Member

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    Now did you? The statements i highlighted, not only contradict what you just said, it contradicts what you have been posting. I maintained that Torque difference between shafts is not the same as locked shafts. You kept telling it was until now you decided to change your tune.

    You went from, its always locked until there is rotational difference, to they lock when there is rotational difference, to now they never lock there is always slip.

    So which one is it?...

    Also your initial definition of a detroit locker was wrong.
     
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  18. Richard Wilks

    Richard Wilks Active Member

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    I understand what you mean, and it might be semantics yes, but the diff is not "locked" in the sense that the wheels are bind together. The two wheels are getting the same torque. This is a FUNDAMENTAL difference and yes, very confusing one, when discussing such matters.

    Of course, there are situations where if 100% of the power is trransfered to BOTH wheels, they will act as a unit, as the video describes, but this "connection" is "broken", its not a solid connection, and thus, its not the same as having a spool or a really welded diff.
     
  19. Richard Wilks

    Richard Wilks Active Member

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    But i will agree with Bazza here. Discussing this is pointless already.

    Clearly, you won't admit i am right about anything, for obvious reasons. You can barely admit that the cars have a problem, when for me and others, that is clear as day. So it might be the diff, it might be the tires, it might be a lot of things. But there is a problem.
     
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  20. GodzillaGTR

    GodzillaGTR Well-Known Member AMS2 Club Member

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    I assume you are joking? Otherwise that logic should apply to the physics guys, beta testers and setup guys for Reiza as well then. I guess they all must have driven every car in the game in real life and at the limit to know how to create them and set them up and provide feedback on them?
     
    Last edited: Jan 7, 2023
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