Import SolidWorks parts to OpenSim

[Karol Marshal]

nice post.

[Ayman Habib]

Hi Davide,

This method supports only exporting geometry (not articulation or any other features supported in CAD). It might be possible to export the geometry from an assembly to a single file but it will come up "glued" together. Ideally we'd support importing of formats that account for articulation (e.g. collada) but that's not available yet, and would require support from the CAD side as well.

Please submit a feature request as we look into these when we make our release plans.

Best regards,
-Ayman

[Vishal R]

Several people have asked on the forum about importing cad models to OpenSim.
Here is my progress so far using SolidWorks.
Transferring whole assemblies is not possible as of version 2.4.

See the attached pdf file for detailed instructions

In this example a part is added to an OpenSim model of the pelvis-femur, Fig. 1. The part is free to rotate.

solidworks part in OpenSim.jpg

Summary of steps:
Determine the coordinate system used by the OpenSim model.
Design the parts in SolidWorks paying attention to the coordinate system.
Find the mass properties from SolidWorks (Evaluate tab > Mass Properties). Find:
Mass
CG location
Inertia matrix about CG
Add bodies, joints, and coordinates via XML to the OpenSim model.

The attachment cannot be downloaded as it reports the file doesn't exist. Could you please provide the link to download.

Cheers!

[Gilbert Ngetich]

hi,
I have managed to import .stl file to OpenSim but my problem now is how to rotate the part in OpenSim. It has attached well but the part is perpendicular to the attached part.
Regards Gilbert

[Ayman Habib]

Hi Gilbert,

Any piece of Geometry that you use has an associated transform to translate/rotate it. you can edit that in the GUI by selecting the mesh/stl geometry and modifying the properties in the "Properties" window. The relevant entry is transform and its value is made up of 6 numbers that represent 3 rotations (in radians) followed by 3 translations.

Hope this helps,
-Ayman

[Marta Carrilho]

Hi,

I added a .stl file in Gait2392 model. When I put it in OpenSim GUI everything seems fine. When I try to scale de model it crashes. Any idea how can I solve this?

Thank you,

Marta

[Euisun Kim]

Thanks for kind explanation!

However, I still have issue on constraining all parts together.
I'm trying to import my exoskeleton model in opensim and make the gait2354model to wear this exoskeleton.
But it is really tricky to adjust values in <location></location>(Location of the joint in the child body specified in the child reference frame.) and <orientation></orientation>(Orientation of the joint in the owing body specified in the owning body reference frame.).

How can I know the reference frame of body exoskeleton parts(which is the child body) from stl model?

Thank you.

[Jimmy Castro]

Hi Ronald,

Could it be a units issue where the size of the part you added is much bigger than the rest of the OpenSim model so the model either ends up too small or embedded inside the imported part? I'd suggest you hide the imported part and see if the model is still visible.

Please let us know how it goes,
-Ayman

Hi ayman do you send me that pdf please I'm trying to add a prosthesis to the model and analyze loads on the march

[Cristian Cordova Espinoza]

Hola por favor si alguien puede ayudarme.Porque, quiero añadir una prótesis a un modelo desarrollado. Muchas gracias. Saludos desde Perú

[Daniel Pina]

John Rogers (the original poster) made a very good tutorial on how to import new solid geometry to opensim. I'm afraid I can't find it anywhere within the documentation, so here is the PDF:

SolidWorks parts to OpenSim.pdf

(350.3 KiB) Downloaded 176 times

(Note: this is not my doing, it's from John Rogers. I've just had this document in my computer for a couple of years already)

I guess this was available in the original first post of this thread from 2012, but it went missing in the meantime.