Conversion from I-DEAS to Rhino3D is not supported yet :(

I-DEAS (Integrated Design and Engineering Analysis Software) is a computer-aided design software package. It was originally produced by SDRC in 1982. I-DEAS was used primarily in the automotive industry, most notably by Ford Motor Company and by General Motors. Now it is owned by Siemens PLM Software. Many I-DEAS technologies formed the basis of the NX system.

Rhinoceros (typically abbreviated Rhino, or Rhino3D) is a commercial 3D computer graphics and computer-aided design (CAD) application software developed by Robert McNeel & Associates. It is used in industries including architecture, industrial and product design, in multimedia and graphic design and runs on Microsoft Windows and OS X. Rhino uses Grasshopper, a visual scripting language add-on, developed by Robert McNeel & Associates.

Rhino is based on the NURBS mathematical model, so it focuses on producing precise representations of curves and freedom surfaces. It allows users to create, edit, analyse, and visualize NURBS curves, surfaces, solid bodies, point clouds and polymeshes.