tie two deformable bodies through a few nodes

[ladopico]

I want to glue/tie/fix the ede nodes of ligaments to the surface of deformable bones, which option on the contact menu is best? the "tied" interface one? is there any other better way?

Cheers.

[maas]

Yes, the tied interface is probably your best choice. That's the only option currently available for tying two non-conforming deformable meshes.

Cheers,

Steve.

[Sara]

Hi both,

I got a same question, but it is preferred to not define contact for the surfaces which I need to glue them. Is it still the only option for gluing two surfaces?

Many thanks,
Sara

[maas]

Hi Sara,

If I understand you just want to "glue" surfaces together without defining a contact interface? This is only possible if the meshes of the opposing surfaces are conforming. In other words, all the nodes of the opposing surfaces coincide. If that's the case, you can just merge the meshes in PreView. To do that, select one of objects and find the Attach button on the Mesh panel. Select the other object in object list you'll see there, check the "weld" option and click Apply. Note that you have to do this before you apply any boundary conditions. The merging may reassign node and facet numbers and as a result invalidate some boundary conditions. Please give this a try and let us know if that worked for you.

Cheers,

Steve

[Sara]

Hi Steve,

Thanks very much for your reply. That works properly

Many thanks and kind regards,
Sara

[Tim.Gadzella]

Hi Sara,

If I understand you just want to "glue" surfaces together without defining a contact interface? This is only possible if the meshes of the opposing surfaces are conforming. In other words, all the nodes of the opposing surfaces coincide. If that's the case, you can just merge the meshes in PreView. To do that, select one of objects and find the Attach button on the Mesh panel. Select the other object in object list you'll see there, check the "weld" option and click Apply. Note that you have to do this before you apply any boundary conditions. The merging may reassign node and facet numbers and as a result invalidate some boundary conditions. Please give this a try and let us know if that worked for you.

Cheers,

Steve

Hi Steve,

Could we get an update on how to do this in the current version of FEBio studio? I don't seem to have the Attach option in the Mesh tab and so my Weld is not working out.

Cheers

[maas]

Hi Tim.Gadzella ,

The merge option is now available from the main toolbar. Look for this icon: merge.png.

To use it, first select the two (or more) objects you wish to merge. Then, click the merge button. Make sure the Weld option is checked, and then click OK.

The same comment as above still applies. Since you are creating a new object that likely will have a different partitioning, it's best to do the merge before applying boundary conditions. If you already had boundary conditions applied, you'll likely have to reassign the selections.

Let me know if you run into any problems.

Best,

Steve

[Tim.Gadzella]

Hi Steve,

Thanks for the quick response. I had been having some trouble with the Merge feature with materials (but no BC's) applied to the parts. I tried it again with only the imported mesh and had it throw an error the first time I tried it but had success on the second attempt. It looks like if I select the two objects in the Geometry tree, Studio crashes out without throwing an error but if I use the Select Objects >> Shift-Click method to select my meshes in the render window it works perfectly!

Thanks!

[maas]

Hi Tim.Gadzella

You indeed need to select the objects in the Graphics View, not the model tree. Thanks for reporting the crash. That should be fixed now.

Best,

Steve