Is there any way to create a *.u3d file format in autodesk inventor?
I had this link actually open in another tab. http://www.quadrispace.com/s/create/
I cant vouch for it but the price seems right.
We used to use a program called Deep Exploration by Right Hemisphere. Unfortunately they were just purchased by SAP and it is quite expensive now.
We have always been the first and primary providers of all conversion software for the mid- and high-level production markets. Ditto for native Inventor and the first + primary U3D conversion system. So, yes, cross conversion of all formats is possible, and natively from Inventor into U3D: