Search found 77 matches

by Ahmet Erdemir
Fri Jun 01, 2018 6:29 am
Forum: Open Knee: A Three-Dimensional Finite Element Representation of the Knee Joint
Topic: Can't get simulations to finish
Replies: 3
Views: 1559

Re: Can't get simulations to finish

Dear Kazuki, We ran the tf_joint_FEBio_V2.feb file to completion a while back using FEBio version v2.1.2.6432. Did you try to use this specific version fo FEBio, at least v2.1? FEBio team regularly updates the version and in some cases this causes convergence issues in models that have been running ...
by Ahmet Erdemir
Fri Jun 01, 2018 6:26 am
Forum: Open Knee: A Three-Dimensional Finite Element Representation of the Knee Joint
Topic: Export of FE-Files to LS Dyna
Replies: 1
Views: 694

Re: Export of FE-Files to LS Dyna

Dear Malou, The Open Knee(s) - Generation 1 model did not separate the tissues into parts. Nonetheless, element sets are defined for each tissue, which can be used to isolate these and use them. About exporting to LS Dyna; you may want to check if LS Dyna imports ,inp file. If not, you may need to w...
by Ahmet Erdemir
Thu Mar 15, 2018 5:54 am
Forum: Open Knee: A Three-Dimensional Finite Element Representation of the Knee Joint
Topic: Segmentation
Replies: 1
Views: 859

Re: Segmentation

Dear Filippos, The IGES files are located in the repository at https://simtk.org/svn/openknee/_gen1/dat/geo/. VolSuite was a free and open source program that we used at the time for segmentation. As I recall, the curves on the tissue boundaries (that come from segmentation) were used to generate ti...
by Ahmet Erdemir
Thu Dec 08, 2016 2:27 pm
Forum: Open Knee: A Three-Dimensional Finite Element Representation of the Knee Joint
Topic: osteoarthritic cases
Replies: 1
Views: 763

Re: osteoarthritic cases

Hi Miriam, oks001 and oks002 are from elderly donors and some cartilage degeneration is expected. We have not done any MRI based grading on the specimens yet. Hence the note "possibly osteoarthritic". The MRIs are available for download in the Downloads section. For an exact evaluation, you may want...
by Ahmet Erdemir
Tue Oct 11, 2016 9:44 am
Forum: Open Knee: A Three-Dimensional Finite Element Representation of the Knee Joint
Topic: Accessing Tibiofemoral Joint Mesh
Replies: 2
Views: 863

Re: Accessing Tibiofemoral Joint Mesh

You may want to download the Open Knee - Generation 1 version g1-s1-v1.0.1.202. This should have the raw mesh and other files. If you want to access the source code repository directly, please check https://simtk.org/scm/?group_id=485 Repository folder structure evolves as we move on the Open Knee(s...
by Ahmet Erdemir
Tue Jul 26, 2016 5:51 am
Forum: Open Knee: A Three-Dimensional Finite Element Representation of the Knee Joint
Topic: Error when running OpenKnee 1.0 (tf_joint.feb) with Febio 2.5
Replies: 7
Views: 2197

Re: Error when running OpenKnee 1.0 (tf_joint.feb) with Febio 2.5

The errors you get with FEBio v2.1 may be related to its compilation for Mac. I advise you to contact FEBio team in this regard. Their forums may be helpful as well.
ahm.
by Ahmet Erdemir
Mon Jul 25, 2016 9:29 am
Forum: Open Knee: A Three-Dimensional Finite Element Representation of the Knee Joint
Topic: Error when running OpenKnee 1.0 (tf_joint.feb) with Febio 2.5
Replies: 7
Views: 2197

Re: Error when running OpenKnee 1.0 (tf_joint.feb) with Febio 2.5

In the file find (at the bottom): <rigid_body mat="1"> <prescribed bc="Rx" lc="2">0.785</prescribed> </rigid_body> <rigid_body mat="1"> <force bc="x" lc="3">0.0</force> <force bc="y" lc="3">0.0</force> <force bc="z" lc="3">0.0</force> <force bc="Ry" lc="3">0.0</force> <force bc="Rz" lc="3">0.0</forc...
by Ahmet Erdemir
Mon Jul 25, 2016 8:49 am
Forum: Open Knee: A Three-Dimensional Finite Element Representation of the Knee Joint
Topic: Error when running OpenKnee 1.0 (tf_joint.feb) with Febio 2.5
Replies: 7
Views: 2197

Re: Error when running OpenKnee 1.0 (tf_joint.feb) with Febio 2.5

The simulations in that file prescribe femur flexion while setting all other degrees of freedom for the femur free. Tibia is fixed by the way. Did you try using FEBio 2.1? That model was running in that version. I suspect that an update on rotation formulations in FEBio v2.5 may have broken this. I ...
by Ahmet Erdemir
Mon Jul 25, 2016 5:33 am
Forum: Open Knee: A Three-Dimensional Finite Element Representation of the Knee Joint
Topic: Error when running OpenKnee 1.0 (tf_joint.feb) with Febio 2.5
Replies: 7
Views: 2197

Re: Error when running OpenKnee 1.0 (tf_joint.feb) with Febio 2.5

If you have not done so, try the updated file (tf_joint_FEBio_v2.feb) released as part of Open Knee(s) - Generation 1 (Version g1-s1-v1.1.0.391). Direct link is

https://simtk.org/frs/download_confirm. ... oup_id=485

Let me know if you have the same issues.
ahm.
by Ahmet Erdemir
Wed Apr 27, 2016 6:14 am
Forum: Open Knee: A Three-Dimensional Finite Element Representation of the Knee Joint
Topic: Problem for Abaqus Conversion
Replies: 1
Views: 950

Re: Problem for Abaqus Conversion

Dear Julie, Your best bet is to get the mesh in a format, e.g. inp, that Abaqus can load and redefine other model parameters in Abaqus. The way you describe may work, once you figure out why it is not necessarily able to import/export the element type. Yet, there are more convenient ways. Open Knee(...