I downloaded the Hexapod Parasolid model from http://www.pkm.org.ua/2013/06/cad-model-arrived.html but cannot open it directly on FreeCAD, Blender, etc.
Then after searching for a CAD converter I found CADExchanger:
Installed it this way:
$ wine msiexec /i cadexchanger_2.5.1_build4182_setup32.msi
Then entered at installed directory:
$ cd ~/.wine/drive_c/Program Files (x86)/CAD Exchanger/bin
And executed it:
$ wine Exchanger.exe
Then clicked on New, imported the Hexapod.x_t file and converted it to many formats.
Update: A nice open-source software for 3D convertion is called Assimp: http://assimp.sourceforge.net. It doesn’t support Parasolid convertion yet, but I think it could change soon.