Introduction: Paper and Tape Jitterbug (Tensegrity Model)
He even went to Harvard (and left).
But for all his grand designs, the most captivating can seem at first to be the most innocuous. Such is the case with the Jitterbug, a deceptively simple yet ingenious bit of geometry. Technically speaking, the Jitterbug is a smoothly transforming cuboctahedron-icosahedron-octahedron-tetrahedron-triangle thing. But practically speaking, it's a lot of fun.
It's not that hard to make one, either.
Here's an animation by kipergok from youtube:
Step 1: Gathering Materials
The model in this instructable is based off of connecting simple modules. The modules will be triangular, made of cylinders connected at their ends by a flexible joint to allow motion and maintain structural integrity.
To make a simple Jitterbug, you'll only need a few things:
Sheets of Paper
Long, thin cylindrical object (i.e. paintbrush, pencil)
The paper and masking tape make up the cylindrical module, and are formed on the paintbrush or pencil. The tape will also be used to connect the tubes.
Step 2: Making the Cylinders
It might make sense at first that making a cylinder from paper is most easily accomplished by rolling the paper over itself and taping the overlap together. You would be right. That's easy.
But structurally, that's not the best method.
To make a strong, light cylinder from paper and tape, wind the paper in a spiral on a form, then tape over in a spiral that winds in the opposite direction. This will maximize the area of overlap - which is inherently strong - and allow the tape, which is stronger, to form most of the real structure. Think of a wrapping paper tube.
1. Cut paper into at least 24 identical strips. Make more to practice the technique at first. My first few definitely didn't turn out well, but after that it was a breeze.
2. Wind paper strip on form so that its tension holds it onto the form. Hold the end so it doesn't unwind.
3. Grab the tape and wind from the roll in the opposite direction. Tear it off before you stick your tube to your form.
4. Repeat 2-3 for all strips.
Boom. You got yourself some cylyndrical submodules. Not too hard to do, and they're stronger and easier to make than the more obvious style mentioned above.
Step 3: Cutting the Tubes to a Uniform Length
The title of this step says it all. But here's a tip: Lay out all your tubes on a strip of tape, then cut them in one fell swoop. You'll make lots of strange confetti. Don't worry, that can be disposed of with ease by your preferred method.
Step 4: Connecting the Tubes
Three tubes connect to form an equilateral triangle. To make a jitterbug, you will need 8 (eight) triangles.
To make the triangles:
1. Lay out the tubes in the pattern below. This will help to keep things organized.
2. Connect the tubes at their ends with masking tape.
3. Repeat 1-2 for a long time or until you've had enough. Or just until all eight triangles have been completed.
Step 5: Assembling the Jitterbug
This is a very exciting step, where all the repetitive work begins to pay off and you slowly see the more beautiful geometry build itself in your hands.
1. Lay out the modules. This isn't just for organizational purposes; each triangle must connect at all vertices to one vertex (point) of another triangle.
2. Using masking tape, connect the vertices of the triangles together in the fashion depicted below.
Step 6: Play!
Now is the best part, where you can get in there and see what sort of strange behaviours this exotic handmade toy is capable of.
See if you can make it behave like the animation in the intro. Remember that the tape is still stiff and may need some training to flex enough to make the smaller shapes.
Keep playing and see what it can do. You'll be amazed at what you discover and even more amazed at how easy it was to make something of such sublime beauty and fun-factor.
What's more, the technique described here can be scaled to any size Jitterbug. That means you could make one a lot bigger or (if you're really patient and dextrous) a whole lot smaller. Really all you need to know is the shape and the two dimensional pattern that folds up to create it. Once you understand that, you'll be free to make this model using whatever materials you like. My methods are suggested only because they happened to be practical. Experiment!
And don't fight forces, use them!