OBJ Export: Error in OBJ file on some vertex normals. --> "vn -nan(ind) ..."

[kima]

Platform / OS: Win 7
KeyShot version:  7.2 Pro
Plugin version: -
Modeling system, including version: CATIA v4/v5 (not sure, will check)
Steps to take to reproduce the problem: -

• import model (step file or catProduct) in keyshot
• export model as obj
• check obj file to find lines like this one: vn -nan(ind) -nan(ind) -nan(ind)

We intend to use blender in our pipeline and obj is our format of choice. However, this bug leads to a fatal error while importing these files because "-nan(ind)"  can't be parsed as a float value(obviously). We've found a workaround for now: we simply ignore all vertex normals in the blender importer script.

This is not a long term solution. Is this a known bug?

[ieatfish]

I'm having the same issue. How do you ignore the normals?