Playing with Sugihara’s “ambiguous cylinder”

The amazing video below came out over the summer:

My favorite memory of the video is my 5th grader seeing it for the first time and saying “dad, that mirror is terrible.” Ha!

Over the summer we printed a few of the shapes and played around with them, but ended up giving them away. Today I was reminded of the shape by this tweet from Dave Richeson:

Thanks to @landisb for suggesting I 3D print my impossible cylinder. And thank you to her for printing my file. I will have to try others. pic.twitter.com/X9Drl3Il4w

— Dave Richeson (@divbyzero) December 15, 2016

I wasn’t sure if the print he showed in his tweet was available, so I found a different one on Thingiverse and started the print so the boys could play with the shape again tonight:

Ambiguous Cylinder Illusion by Make_Anything on Thingiverse

As luck would have it, though, Brenda Landis did put the print from Dave’s tweet on Thingiverse:

Here ya go! https://t.co/rdkBMe5ppN

— Brenda Landis (@landisb) December 15, 2016

Here’s the direct link:

Brenda Landis’s “Sugihara’s Circle/Square” on Thingiverse

So, now we had two of them to play with 🙂

I had my younger son play with them first:

My older son went next:

So, a super fun project and another great example of how 3d printing can help kids see some amazing math-related ideas. Super duper thanks to Dave Richeson and Brenda Landis for sharing this print.