FFB on front wheel drive cars

Discussion in 'General Discussion' started by blagger, Jun 3, 2017.

  1. Lazza

    Lazza Registered

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    As far as I know recent TGMs have 55-65 nodes (rim to rim), and around 200 sections (longitudinally around the tyre). I'm not sure that correlates directly to what's used within the model itself though, as obviously you can interpolate those just the same way you can interpolate tables for a simpler model.
     
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  2. McFlex

    McFlex Registered

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    Yep thas was me. Although that 397 stated in thier may update that they think about upgrading the honda to the newest cpm model i think i allready happend at least to the medium tires and the maybe didn't notice or it was done by accident or just a wrong file they uploaded.
     
  3. LokiD

    LokiD Registered

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    really interesting read there mate. Will play with those settings when I get a chance. Cheers.
     
  4. boblevieux

    boblevieux Registered

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  5. SPASKIS

    SPASKIS Registered

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    I have been reading Michael's blog and for what I have read, the simulation tool seems to be very well done. The mesh detail seems sufficient and the construction of tire regarding layers is also taken into account. From load/tire deflection point of view the tool seem to provide very accurate results.

    While in terms of stiffness the approach seems to be flawless, I have some doubts whatsoever with contact patch model itself and validity of lookup table strategy for determining pneumatic trail and slip angle. I didn't fully understand what combinations of cases are analised in order to generate look up tables. In the tyre technology PDF it is stated that only 72 cases are run but that they can be increased. I didn't find an equivalent figure in the blog. However according to the reported calculation time this recommended number seems to have increased by 5-10 in between both documents.
    I will try to better understand which are the DOF available for this batch tests and what kind of results are provided to the tgm file. 72 loading cases seem to me very few to properly adress non linear behaviour of the real model in the contact patch under the combination of so many variables affecting final result. It should be also noted that in the blog, the picture show very weird values for pneumatic trail at zero slip angle.

    As a summary in a first glance I would expect a very realistic behaviour in terms of tire deformation under loads but I would expect CPM not benefitting form the huge potential of tyre tool due to the huge number of tests that would be required to cover the whole range of variables on which the pressure distribution at the contact patch depends.
     
  6. kevib1

    kevib1 Registered

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    I have noticed that in both the Clio and Civic the steering lock is 900°. I'm sure it wasn't in previous versions an it seems far too high for a modern racing car.
    I don't know what it should be but setting it down a couple of options, 600 or 480ish I think gives a much better feel all round and the cars are again a barrel of fun!
     
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  7. LokiD

    LokiD Registered

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    agree or just put the angle down, i use about 22 for the civic..
     

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