About this 3D model
The famous expanding and contracting ball toy that also makes excellent structural support for whatever sparse scaffolding you need. Basically, if you can design it as a geometric solid, you can probably make a collapsible version with this. In a pinch, also doubles as a jack or a reacher-grabber claw.I was looking to build a NautilusX model http://en.wikipedia.org/wiki/Nautilus-X and realized that Thingiverse didn't even have a Hoberman sphere library. It uses one-way snaps might be useful for other projects too.I'm not nearly clever enough to invent the Hoberman sphere. Thanks to Charles Hoberman for the original concept and helpfully detailed drawings.