# Turing, Nets, and More Yoshimoto

Welcome to this week’s Math Munch!

The Turing Tenner

What you see there is a 10 pound note. You know, British money. So who’s that guy on there? Must be a president or king or prime minister or something, right? NO! That’s Alan Turing, one of the most important mathematicians of the 20th century. During WWII, he was a codebreaker for the Allies, intercepting German submarine codes. His analysis of the Enigma Machine was a huge turning point in the war. (video explanation)

In England they put the queen on one side of the money, but the other’s used for significant Brits. Charles Darwin is currently on the 10 pound note, but these things change, and there’s a petition to get Turing on the ten. A Turing Tenner, as they call it. It’s all part of Turing’s 100th birthday celebration.

Google’s homage to Alan Turing

Since Turing did some of the earliest work on computing theory and artificial intelligence, Google paid tribute to the computer legend with a recent doodle. It’s a fantastic little puzzle game based on his work. I’ll let you figure it out, but definitely try this one. Click here to play!

In last week’s munch, Justin introduced us to the Yoshimoto Cube, and we’ve kept on thinking about it.  Here’s a couple simple templates for making one cubelet.  (template 1, template 2)  Make 8 of those and hinge them together with some tape.  I made a short video to show you how to connect them.  But it didn’t end there!

A flat template for a 3D model like that is called a net or a mesh.  Do you know any nets for a cube?  There’s actually lots.  Check out this site, where it’s your job to figure out which nets fold up into a cube and which ones don’t.  It’s a lot of fun.  Here’s another net site showing lots of nets for a pyramid, dodecahedron, and a whole bunch of other solid shapes.  How many do you think there are for a tetrahedron?  Can you design one for an octahedron?

The Monster Mesh

I spent some time this week trying to design a better net for the

The Mega-Monster Mesh
A one-sheet model for the Yoshimoto cube.

Yoshimoto cube, and I think I succeeded!  The tape on my hinges kept breaking, so I wanted to try to make paper hinges.  With my first attempt, which I called The Monster Mesh, I was able to design a net for half of the star.  Down from 8 tape hinges to 2 was a big improvement, but last night I got it perfect!  Using my new version, The Mega-Monster Mesh,  you can make the entire cube without any taped hinges!  The model is pretty complicated, so if you want to give it a shot, feel free to email us at MathMunchTeam@gmail.com with any questions.

Finally, something I’m really really proud of.  Justin and I spent most of Sunday afternoon on the floor of my apartment making a stop motion animation of with Yoshimoto Cube models.  It’s called “Yoshimoto Friends,” and we hope you love it as much as we do.  (We used the free iMotionHD app for iPad and iPhone, in case you want to make your own stop motion animation.)

Bon appetit!

Update:

I made another video showing how the mega-monster mesh folds up.  Here it is, acting like a transforming bug!

### 9 responses »

• Thanks Rachael, I’m quite proud of it. Hope you’ll check us out in the future, maybe share us with students.

1. The stop motion animations were really cool!! Honestly I can’t pick which video is my favorite 😀 I love both of them. I was wondering how you make one of the Yoshimoto cubes?? I’m interested in making one. On the first video, I have to admit, when the blue one went inside the red one, I had to replay it again because I wouldn’t have thought that the red one and the blue one could fit inside each other so perfectly. I’m also amazed when you got the blue one inside the red one and then you kind of like folded them together and then eventually the red one was the one that came out of the blue one. I’m still watching them over and over and over again. Thanks for the video!

2. Both videos are very cool. I though it was really interesting that Yoishimoto cubes are able to change to a star like object to a cube. I was also amazed that both cubes are able to fit perfectly in each other. The Yoshimoto cube reminds me of a toy cube I had that was able to transform to different objects. I definitely want to make a Yoishimoto cube now!

3. Pingback: Le cube de Yoshimoto

4. Wonderful net. Love the stop motion videos. I would love a video that actually demonstrates how to assemble the thing. I’m having some difficulty figuring out which interior edges to cut.