Hi Non-Twisty Puzzles fans,

Cubic Hourglasses is a concept by Bram Cohen. The puzzle has four hourglass-shaped pieces, and a three-quarter-circle piece. The object is to get the latter piece from the top to the bottom. The pieces do not only slide like in a sliding block puzzle. They also turn, pivot and skew.

Watch the YouTube video.
Buy the puzzle at my Shapeways Shop.
Read more at the Shapeways Forum.
Check out the photos below.

Enjoy!

Oskar

Interesting idea, though I imagine trying to manipulate the parts through the cage could be quite frustrating. Solving puzzles should be limited by speed of thought rather than physical manipulation, and one of the reasons why Rubik's Cube became so popular is all the constraints were internalized. Still, I'm sure this puzzle will seed lots of new ideas in this direction.

I love the idea. Glad to see that it's in a more finished state.
Could some very small spaces inside of the cage be filled so it's a bit less wiggly?

Interesting puzzle and interesting shapes. Very original 3D sliding block idea. As for the question asked in the video... I would think the proof would entail counting the number of states of the puzzle and then checking rather the three-quarter-circle piece was upside down in any of them. Surely as this puzzle basically only has 5 pieces and you might even be able to treat the 4 hourglass-shaped pieces as identical I would think it must have a rather small (less then a 1000 if not less then 100) number of states.

Carl

I made a video response explaining my answer to your question posed in the video.
VIDEO

Surprisingly it isn't. Even the first prototype surprised me by being very easy to manipulate and engaging for many people despite the complexity of the movement. People find all the motions intuitive and easy to do, even though there are four of them.

I should point out that the question Oskar is asking isn't whether the corkscrew can be flipped upside down, but whether it can be flipped upside down with everything else in a solved state. The other question he didn't ask is what's the smallest number of moves which can be used to get the corkscrew to the opposite side and the faces all re-solved.

Bram, what sequence of moves can you do to flip the corkscrew piece over in the top layer? as i understand the puzzle, i don't see the piece being flipped at all.

First you do a screw move, to make it so that there are two voxels of the screw on the top. Then you rotate it, so there's one. Then you do a screw the opposite way, so there are two again. Then you do a rotation to the other position where there are two, and do a final screw, and it will be back on the top but upside-down.

I posted a video demonstrating how to flip over the corkscrew and talking about the puzzle generally -

https://www.youtube.com/watch?v=xZI8wvJyEf0

I tried to make it a reply to the original vido, but youtube appears to be borked.