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Wheel offset?

Jesper Slattengren
So when I modify the tire/wheel, there is a field for wheel_offset. Which makes perfect sense. The wheel center is a design position on the intersection between the spin axis and the mating surface where the wheel is bolted on. On this design, different wheels can be used with different offsets. That will among other things change the scrub radius.
The problems are
  1. This parameter is not used by anything. Changing it does not move the tire in or out.
  2. Using the suspension testrig, there is nowhere to set this parameter. As this is using a testrig tire that does not expose this parameter. I can change it by manually search for this variable and change it. But it looks like an oversight. And it does not change the scrub radius or anything else in the simulation
 
OK, it is easy to fix for the full vehicle tire template, but it seems wrong to me.
 
Anyone else looked into this? @Martin Kieltsch​ you must have fixed this?
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    I was understanding the first one: Cm Offset as moving the CG of the wheel part, and second one center offset just as visualisation of center of wheel (with that cylinder).
     
    in help is written: Enter the offset of the wheel-center geometry along the z-axis of the wheel part. And i was thinkining as geometry for part.
    Capture
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    Visualization... It is useful to have a visual feedback. But more important is where the forces from the wheel acts.
    But it is really a question of where the center plane of the tire is. And that is disconnected from the wheel center.
    As I explained, the wheel center is a design parameter of the suspension (really a sort of misnomer as it is not connected to the wheel). On that suspension you can put on any wheel that is the right size and the right bolt pattern (and clears the calipers). It is not uncommon to have different wheel offsets on the same suspension to fit a wider tire for a stronger engine. And I don't want to have to change my suspension model to test the behavior for different wheels.
    So the offset will move the tire itself in or out.
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    Well, that was an interesting picture. But as I said, it's only geometry and does not matter.
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    I was always using hardpoint to move wheel center. I was thinking about center offset in wheel part as just geometry offset without real usage apart visualisation (but if see hardpoint wheel center, why i need cylinder).
     
    Your clarifation about center offset was interesting with real usage, maybe this was intended use for center offset and there is just bug.
  • 0
    As usual it's better to have important things implemented on your own.
    So just use own suspension templates that have a construction frame parametrized that's later held by the communicator wheel_center. (i.e. all A/Car stuff is attached to that relocated CF)
    In our case we have a parameter variable for the offset in question ("Einpresstiefe" in German) that moves the wheel_center marker along the spin axis relative to a hardpoint for "wheel center".
    Unfortunately that sometimes creates user misunderstandings as they expected the wheel center at the hardpoint and did not check for the parameter being unequal to zero.
    In the standard wheel subsystem you have to use a zero offset as it's already done in the suspension template.
     
    The advantage of this method: You can easily adjust the offset the same way in suspension and full vehicle analysis
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