Simple Automata Extravaganza

[Federico Tobon] from [Wolfcat Workshop] spent Makevember in 2017 building a series of fascinating automata using the most basic of craft supplies and simple tools in his workshop. Using a combination of rigid materials such as wooden cubes, popsicle sticks, and paper clips and pliable ones like paper and rubber bands, his creations are way more delightful to play with compared to fidget spinners.

There are no assembly guides, instructions or building plans, but for a hacker, one look at these designs ought to be enough to glean how to build one, with some trial and error to get it right. And that is exactly what [Tobon] found to his delight. After sharing animated GIFs of his creations on social media, numerous other hackers built and shared their own versions of his designs as well as building some new ones.

He posts several other useful resources, some of which were the inspiration that got him started making these automata. All of them are pretty interesting, so do take a look at them too. There is a lot that young kids can learn from building these little machines, given some guidance and help from the elders. But the way we see it, it’s likely the old folks will enjoy them more.

The video after the break compiles all of the little machines for six minutes of viewing pleasure.

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When Unfolding An STL In Software, Math Isn’t The Tricky Part

Some time ago, [Trammell Hudson] took a shot at creating a tool that unfolds 3D models in STL format and outputs a color-coded 2D pattern that can be cut out using a laser cutter. With a little bending and gluing, the 3D model can be re-created out of paper or cardboard.

There are of course other and more full-featured tools for unfolding 3D models: Pepakura is used by many, but is not free and is Windows only. There is also a Blender extension called Paper Model that exists to export 3D shapes as paper models.

What’s interesting about [Trammell]’s project are the things he discovered while making it. The process of unfolding an STL may be conceptually simple, but the actual implementation is a bit tricky in ways that have little to do with number crunching.

For example, in a logical sense it doesn’t matter much where the software chooses to start the unfolding process, but in practice some start points yield much tighter groups of shapes that are easier to work with. Also, his software doesn’t optimize folding patterns, so sometimes the software will split a shape along a perfectly logical (but non-intuitive to a human) line and it can be difficult to figure out which pieces are supposed to attach where. The software remains in beta, but those who are interested can find it hosted on GitHub. It turns out that it’s actually quite challenging to turn a 3D model into an unfolded shape that still carries visual cues or resemblances to the original. Adding things like glue tabs in sensible places isn’t trivial, either.

Tools to unfold 3D models feature prominently in the prop-making world, and it’s only one of the several reasons an economical desktop cutter might be a useful addition to one’s workshop.