Hi,

I have a model that involves spherical rod ends, and I am having trouble modelling them appropriately in SolidWorks FEA. For now, I would be satisfied with allowing rotation about one axis (in reality the rod end has total rotational freedom, up to a point). So I set up a simple model to make sure I understand what I am doing and that everything works as expected: I made a pin, and I modeled the rod end as a rectangular bar with a hole through it.

As a first check, I loaded the bar in tension along its axis. There is a stress concentration near the pin, as expected, and besides that the bar has the stress I expect (by taking force/area).  Next, I want to load the rod at some small angle, and see that the bar rotates until the load is in line with its axis again. If it works as expected, I should see identical results to the first case.

Here is what I have tried:

I add a pin connector between the inner face of the hole in the rod and the pin.

I add a no penetration contact between those two faces.

I do both of the above.

In any case, I see bending in the rod, which means my model is not working. I feel that this must be a very simple thing that I'm missing. Any ideas?

I also tried using a fixed hinge, but I want to model rotation about an axis that is free to translate, so I think that is not applicable.

Edit: I've added a couple pictures to illustrate the setup and a couple of the results. Sorry for the poor image quality, I am working remotely and don't have as many options for taking screenshots.

Thank you thank you.