Results 1 to 10 of 11

Thread: Problem with yaw moment diagram

Threaded View

  1. #1
    Junior Member
    Join Date
    Nov 2016
    Lund, Sweden

    Problem with yaw moment diagram

    Hi everyone,

    my name is Alexander and I write from Lund Formula Student in Sweden. I'm having some difficulties producing yaw-moment-diagrams with constant corner radii. As can be seen in the picture below, the diagram with infinite corner radius looks reasonable(?) (I'm using the SAE-axes convention), however, the one with a constant corner radius (and therefore varying yaw-rate which affect slip-angles) seems incorrect to me. For example, when beta=0 and delta=0 the yaw-rate should be zero(?) and therefore all slip-angles should be zero as well (which also means that all isolines should be shifted vertically compared to the current diagram). Therefore, it seems to me that the yaw-rate converges to an incorrect value in my iteration loop. When there is no yaw-rate (infinite corner radius), the slip-angles and lateral acceleration converges to reasonable values. Any hints as to what I'm missing? How do you correctly calculate the slip-angles iteratively when they depend on vehicle speed and yaw-rate? I'm using a four-wheel bicycle model with parallell steer and equal slip-angles left to right on each axle.

    Some car parameters and the beta/delta sweep range differ between the diagrams, so don't compare absolute values. The solid lines are the delta isolines and the dashed lines are the beta isolines.

    Thanks in advance!

    Last edited by prox; 04-07-2019 at 09:45 AM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts