Vehicle Dynamics Insights 004 | Ackermann Steering Geometry w/ Mike Law

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  • เผยแพร่เมื่อ 30 พ.ย. 2024

ความคิดเห็น • 9

  • @zzvyb6
    @zzvyb6 8 หลายเดือนก่อน +1

    A proper & robust Ackermann geometry must be defined by at least 2 turn radii. Otherwise, there is an infinite number of solutions to produce the single only value, involving static toe, compliance and the steer arm geometry. Anti-Ackermann is an understeer REDUCTION technique. It also gets mixed up in mid-g_level steering gain issues, especially for a car that's slightly oversteering to begin with and you want to have a specified limit behavior. A higher Max_lat usually comes along with this too. But, like everything else, you can overdo it. The rear should also be subjected to mods to maintain your balance. Once you know the minimum turn radius and one other high speed turn radius (plus the tire data). The solution is fixed. Keep in mind that there are 3 types of tire properties that you need to be aware of: Peak Fy advancing in slip angle with increased vertical load, no change in Peak Fy slip angle with load, and Peak Fy slip angle reducing with Fz loading. The first is more common, but plenty of the other ones around... Oh, and you need to know your wheelbase, too. Sometimes BOTH of them....

    • @WaveyDynamics
      @WaveyDynamics  7 หลายเดือนก่อน

      Yeah right on! I like the framing of it as an understeer reduction technique 👌🏾. I’ve always held it as a tool to maximise a_y but that’s a more subtle and nuanced take on it.
      Mid g steering gain as in it increases gain when tyres aren’t saturated?
      Have never come across tyres which demonstrate peak Fy at reducing slip angles, in the linear range at least.. we’re talking radial ply?
      - Jahee

    • @zzvyb6
      @zzvyb6 7 หลายเดือนก่อน

      @@WaveyDynamics I sent you an email (theoretically) with a presentation on all of this subject. Did you get it ?

    • @WaveyDynamics
      @WaveyDynamics  7 หลายเดือนก่อน

      @@zzvyb6 Hey Bill.
      Yeah i got it, i sent you an reply back over the weekend - did it get relegated to junk? - Jahee

    • @jesseadcock247
      @jesseadcock247 5 หลายเดือนก่อน

      @@zzvyb6Would you be willing to share the presentation with me by chance?

  • @supersevenhead
    @supersevenhead ปีที่แล้ว +1

    Curious what Ackerman Indycars run at Long Beach (Queens hairpin) and F1 at Monaco (Loew's hairpin).

    • @WaveyDynamics
      @WaveyDynamics  ปีที่แล้ว

      Haha yes i would be too! 🙂 - Jahee

  • @bigbothoee8617
    @bigbothoee8617 ปีที่แล้ว

    What would happen if you have a front rack steering system the rack is parallel to track rod ends, I'm getting anti akerman
    If I moved the rack behind the track rod centreline will this make a positive akerman?

    • @WaveyDynamics
      @WaveyDynamics  ปีที่แล้ว

      Try and sketch it out in CAD and see for yourself 🙂