Landing Gear Rim Size

[Mike Kelly]

I am trying to define a landing gear on the attached model. It is a scale model, so I am using manual dimensions instead of a standard tire. I have set my model units to cm and want a tire size of D4.0 W1.0 and a rim size of D3.0 W1.0. The tire seems to size correctly, but the rim does not. Can you tell me how to configure this correctly? I have been following along with the video from the 2025 workshop.

[Rob McDonald]

Thanks, I'll try to see if I can sort something out.

The tire model is probably a bit overcomplicated for many purposes.

I did the best job I could of implementing the full TRA (Tire and Rim Association) parametric tire and rim model.  This means that there are actually several numeric solves that need to occur to construct a tire.  If these don't converge for some reason, then strange results can occur.

I'll try to fix this, but it will probably also be a good idea to add a simplified tire / rim model that is faster and guaranteed to work every time.

Rob

On Tue, Sep 16, 2025 at 9:59 AM Mike Kelly <miked...@gmail.com> wrote:

I am trying to define a landing gear on the attached model. It is a scale model, so I am using manual dimensions instead of a standard tire. I have set my model units to cm and want a tire size of D4.0 W1.0 and a rim size of D3.0 W1.0. The tire seems to size correctly, but the rim does not. Can you tell me how to configure this correctly? I have been following along with the video from the 2025 workshop.

--
You received this message because you are subscribed to the Google Groups "OpenVSP" group.
To unsubscribe from this group and stop receiving emails from it, send an email to openvsp+u...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/openvsp/8346d9d5-4b06-46d8-b0ab-5fa8987f2535n%40googlegroups.com.

[Mike Kelly]

Thanks, Rob. It looks like I have an easy workaround by changing my Model Units from cm to m. This should work fine for the geometry analyses I plan on doing.

[Rob McDonald]

Thanks for that additional information.  That may help me track down the issue...

Rob