JC Constantin’s Welle / Wave

Puzzle-wise there are quite a few variations on the Gray Code theme out there.

They can all trace their roots from the ancient Chinese Rings puzzles, through to more recent variations in puzzles like Mag-Nif’s The Brain and Thinkfun’s Spin Out, but more recently they have been “owned” by the likes of Kugellager.  There are a couple of versions of Kugellager out there with varying levels of moves required to solve them, but my favourite is now Welle…

 

Three adjacent wavy tracks interfere with a sliding panel that allows the ball bearings to progress up and down the tracks … but the implementation is sublime as the balls rise and fall on their own as you move the slider left and right, making the 100-odd moves an absolute pleasure … and once you get all three balls to the bottom, the cherry on the top is that you can remove the balls from the their holes and pop them back in at the top again thanks to the clever little one-way holes at the top of the tracks. 

 

It’s not the biggest or the baddest, but it’s definitely the most elegant variation on the theme out there…

Goetz Schwandtner has written an excellent paper on this family of puzzles – including Welle – over here … if you haven’t read it yet, it’s highly recommended!