In the present article the use of a spherical joint in Radioss and how to set it up in HyperMesh are presented.  The spherical joint is a type of joint available within /PROP/TYPE45 (KJOINT2).

The model created to showcase the use of the spherical joint and contains 3 identical cylindrical tubes.  Figure 1 shows a brief explanation of the model.

Figure 1: Model layout

As we can see the first cylinder is fixed in one of his end, while the other two cylinders are tied connected between them.  Between the first and second cylinder the spherical joint is defined.  The third cylinder created a 90 deg angle with the second in order to showcase more clearly the movement of the structure.  Finally, gravity (/GRAV) is applied to force the body to move around the joint.

Specific details on how to set-up a this spherical joint are described in the attached PDF presentation file.

In Figure 2 the movement of the model is displayed.

Figure 2: Spherical Joint Movement

The following video provide details on how to set up the displayed spherical joint using Altair HyperMesh.