Drive to the limit, look at telemetry data of Alien Sim Racer and real Pro driver

Discussion in 'General Discussion' started by Joe, Dec 17, 2015.

  1. Lazza

    Lazza Registered

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    The thesis shows a straight line force response in both real life and rF1; altering STS in rF2 changes the shape of the output, so it's no longer a straight line. Is that better? Sort of...

    What's wrong with just reducing the FFB level if it's producing too much force on your wheel? Then you can keep your straight line, and make the actual forces more realistic if that's what your calculations show.

    I think Paul's reasoning with lowering the STS is very different, by the way.
     
  2. David O'Reilly

    David O'Reilly Registered

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    Senna blipped the throttle mid corner inthe turbo cars to keep the turbo spinning and so have less lag. In the Honda NSX it was a different scenario. The early NSX had a lot of understeer and he was provoking the rear to slide to defeat the understeer.
     
  3. unknwn

    unknwn Registered

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    @Paul Loatman
    Are you using Accuforce wheel?
     
  4. DrR1pper

    DrR1pper Registered

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    In the "dynamic resistance" but "stationary" picture, where there are two equal but opposite torques acting on the steering wheel in the background, they would simply cancel each other out. So if you "did grab the wheel, and tried to turn it" it would feel no different to not having those two equal but opposite background torques.

    Also, you can't have two torque outputs from an ffb wheel simultaneously. Well, not unless it has at least 2 motors running independantly and a sim programmed for it.
     
  5. Ozzy

    Ozzy Registered

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    Doesn't rF2 calculate the centrifugal force of a tyre acting on the steering?
     
  6. Ozzy

    Ozzy Registered

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    That is what I meant. The centrifugal forces also should lead to some dampening effect but dynamically depending on how fast the tire rotates.
    In case I confused something, I mean the force you feel if you hold a rotating bicycle wheel between your hands and then try to change direction.
     
  7. Ozzy

    Ozzy Registered

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    The oscillation is probably a problem of FFB wheels. I think their motors cannot "hold" a specific position. Don't know if servo motors can do this?

    But in fact as long as you hold the wheel in your hands it shouldn't be a big problem?
     
  8. Ozzy

    Ozzy Registered

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    Why damping and friction do not cause oscillation is pretty obvious imo.
    These effects don't try to position your wheel. They simply counteract a steering movement regardless of your wheel position.
    The forces which try to position your wheel at e.g the center will cause oscillation if the wheel constantly overshoot the desired angle.
    This problem is pretty old. Maybe you could add some sort of prediction into the FFB algorithm but I don't know if the software itself knows where the wheel should stop?


    Edit: thinking about this, I came to conclusion it cannot work because the prediction also would have to know the inertia of the wheel (with your hands and arms[emoji12] )
     
    Last edited by a moderator: Dec 21, 2015
  9. DurgeDriven

    DurgeDriven Banned

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    I like enough centre force that when you screw lock when parked the wheel will want to return a little of the way.


    All you experts out there sitting in garage turn your steering full lock, is there any force exerted wanting to straighten the wheel slightly ?

    If not and your wheel just sits there ......then it is canned.
     
  10. Ozzy

    Ozzy Registered

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    Hmm, I think the friction is dynamic. If you are not moving, the wheel is extremely "dampened". And if you're rolling the friction is nearly neglectable imo.
    For me the dampening should simulate the resistance of the steering system internals and I don't know why this should be dynamic.
     
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  11. Ozzy

    Ozzy Registered

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    I was talking about position based feed back because you were talking about oscillation...[emoji12]
     
  12. Ozzy

    Ozzy Registered

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    OK I think I was not clear. With friction we mean
    A)tire friction, which is in fact dynamic and I bet simulated in rF2.
    B) the friction in the steering system which is IMO static and simulated with dampening/friction effects

    So I think everything is there and wondering why you use such an high amount of damping? If you use it to eliminate oscillation than I think that's just to much, maybe try lowering the multiplier instead.

    The problem is that dampening only masks the underlying problems of oscillation and eliminating dampening when in the air would be a dirty hack and would also be unrealistic for the steering system (not for the tire friction)


    Edit: Forgot C) centrifugal forces, dynamic but should also be felt in the air as long as don't hit the brakes
     
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  13. Ozzy

    Ozzy Registered

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    Never used an AF but I totally agree with you I also has dampening enabled in rF2 because I feel it's more realistic. But it's not meant to kill oscillation and I can't imagine a thing which could dynamically increase dampening to prevent it. How could the software know if your wheel oscilates or you are driving slalom on purpose?
     
  14. Ozzy

    Ozzy Registered

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    Maybe the centrifugal force is really missing? With an AF you should easliy feel the dampening getting more and more as you drive faster? Does this not happen, always thought it is because of my weak G25.
     
  15. Ozzy

    Ozzy Registered

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    I'm confused why should centrifugal forces not increase dampening? Dampening is nothing special FFB wise. Damping does not hold your wheel, it is simply only active when the wheel gets turned by another force and inactive when not ...btw. exactly like turn a wheel which rotates between your hands, remember :p

    Don't get me wrong. I'm with you, there maybe something wrong missing, thats why I brought up this centrifugal forces thing. :D
     
  16. unknwn

    unknwn Registered

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    Above shouldn't make it impossible to have dynamic dampening/resistance that counteracts the unnatural bouncyness (at least by using "left or right" torque).
    Have you tried gyroscopic effects in AC? It dynamically adds resistance in the center as you speed up, dampens other forces and removes pretty much all of wheel oscillations and bouncing, however it makes the wheel sloppier, which is the reason why I am not using it. Either way in both cases (with or without this effect) my wheel appears to be either too bouncy or too slow to countersteer. Something in the "middle" would feel more natural.
     
    Last edited by a moderator: Dec 21, 2015
  17. Guimengo

    Guimengo Guest

    Centripetal, not centrifugal force. The former is real and has an equation, the latter is an "imaginary" interpretation of the former.
     
  18. Ozzy

    Ozzy Registered

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    Ahh thanks, wasn't sure about that.
     
  19. Joe

    Joe Registered

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  20. DrR1pper

    DrR1pper Registered

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    I think it's either already implemented or it can't be (or rather not in a way that you can/want to notice/feel it).

    Small example problem that may shed light as to why. How do you simulate constant speed on an ffb wheel under any condition?
     
    Last edited by a moderator: Dec 25, 2015

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