When we tie up a belt or paper tape well, a knot that is called "Chiyo-Musubi" is completed. In Japan, it is said to be a lucky knot. We can see it as a Chopsticks bag, and others.
The craftsman wanted to make a work based on this shape. It has 19 moves, and the movements cross each other. It was much more difficult to make than expectation. Well, the shape of this "Chiyo-Musubi" is a Pentagon. But, it is also possible to make a Heptagon. Though, there is no plan to make it as a Karakuri work!