Cylindrical fiber orientation

[ladopico]

Hi,

I have models of meniscii, and as they are horn-shaped, I'd like to define fibers that run along them in a circular way, through cylindrical coordinates for example. I have seen there is spherical fiber orientation but it would consider the radius and not the tangent. Is there a way to do it or would I need to program it?

Cheers.

[maas]

Hi,

Currently, there is only limited support for complex fiber distributions in PreView. Although in the FEBio input file you can define a fiber direction for each element, you will have to create some custom code yourself to create the element data.

FYI, creating more complex fiber distributions is high on my todo list for PreView features. You may see improved support for this in upcoming versions. If there is a specific functionality you need, make sure to create a feature request so I can take it into consideration.

Cheers,

Steve.

[orsialex]

My Method for Meniscal Fiber Distribution

Hello All,

I have been trying solve the same problem. However, I may have found a good way around it. If you use an orthotropic material model, and designate a local material axis you can achieve the fiber directionality you are looking for. The thing is, you have to make sure your mesh is uniform in so much as there is edge consistency for the local node numbering. If there are sections of your mesh with different node numbering schemes, this method will be very hard to implement.

I have been able to apply it to my model, however FEBio is not liking the <mat_axis type="local"> #,#,#</mat_axis> command I input. For some reason I am getting a syntax error. Maybe if someone else tries this as well, they could help me debug!

Thanks, and Hope I have helped.

-Alex

[maas]

Hi Alex,

Are you defining the mat_axis item in the ElementData section? If so, this section only supports the explicit definition of the a and d vectors. If you want to use mat_axis, you have to place this item in the material definition instead. Please give this a try and let me know if that works.

Cheers,

Steve.

[orsialex]

Hi Steve,

I had copied and pasted the code from the um PDF...It changed the font of the quotation marks, and FEBio didnt like it haha. Gotta love syntax. Its all good now!

Thanks anyways.

-Alex