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What would cause an error with "straight line" steering input but not free/locked?

Jonathan Corno
error part 2
error part 1
When I run a straight line acceleration event using free or locked steering input, the event runs and the car performs as expected, but when I run the same event using straight line steering input, the event errors
  • 0
    With the straight line, you are introducing a feedback controller in the system. There are a lot of things that can go wrong.
    The most common is that the steering goes the wrong way. Verify in a suspension assembly that a positive steering motion is to the left and that the wheels actually turn to the left as well. If not else, reverse the direction of one of the couplers in the steering column.
     
    Second, verify in the full vehicle Setup Parameters that the steering ratio and rack ratio are set to proper values.
     
    If this still not work, you might have to work with the controller parameters in the event xml file. Use the event builder and load the event that was created automatically. Adjust the LatPth parameters first, that is usually enough.
    The default values are suitable for a sporty passenger car and absolutely unsuitable for a full-size truck or 6-wheeled 8 ton vehicle for example.
  • 0
    I checked that turning the steering wheel a positive angle turns it left, and the wheels also go left so that seems correct,
     
    I had a gear ratio of 6.614 for 360 degrees of steering wheel rotation to achieve 0.95 inches of rack displacement, but for some reason when I ran a step steer event, the event would fail unless I raised the ratio significantly. I correspondingly increased the steering wheel angle and the event would run as expected, but straight line steering is still erroring.
     
     
  • 0
    That indicates that you should look at the LatPth parameters. If it works better when you make it more sensitive, means that increasing the gains could achieve the same effect.
     
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