Selection problems when reducing meshes

[Anonymous]

Hi there!

I'm a complete beginner in 3D-modeling so the answer to this might be something stupidly simple. I've imported an .obj mesh from MakeHuman into Fusion and now I'm trying to reduce the facet count. 

I'm following this tutorial:

https://knowledge.autodesk.com/support/fusion-360/getting-started/caas/screencast/Main/Details/a281d...

In step 5 though, Fusion won't let me select the meshes, pleas see the attached screenshots, I can't select it in either the browser or directly by dragging a box around it.

I've attached the file I'm working in as well as the mesh I imported.

Please help a Newbie 🙂

Regards

Fredrik

[TrippyLighting · Accepted solution]

The mesh workspace in Fusion 360 is meant for .stl meshes, which are exclusively triangulated meshes. The very least common denominator amongst all 3D geometry data. Those, as you have already leaned will need to be reduced to a face count preferably under 10k so they can be converted into a BRep (solid geometry, or NURBS surface).

However, .obj meshes from Makehuman are high fidelity quad meshes that deserve much better! That "quad" term makes all the difference!

Once imported (with the timeline off) they can be converted into T-Spline. Then you can turn the timeline on, if you wish. Usually after T-Spline conversion they are converted into a BRep directly and then are mathematically precise surfaces as opposed to the triangulated .stl garbage.

This mesh wil probably not convert directly into a BRep and will return an error message when you try to do so. HTe reason for this is the Fusion 360 does not allow for self intersecting surfaces (surfaces that fold over themselves)  and you'll have to manually fix the mesh by editing the T-Spline. The problem areas with Makehuman meshes are the mouth and ear areas.

I personally clean usually clean this up in Blender before going into Fusion.

Last remark: .obj files can also contain triangulated mesh data and then are as valuable (or not) as .stl files.

[Anonymous]

Thanks, that was a really great reply, just what I needed to know! Now I can see the profile of my dummy when doing section analysis rather than it just being messhy 😉