[shiura]’s Hollow Clock 3 is a fantastic 3D printed take on a clock movement that uses a hidden mechanism to pull off its unusual operation. The Hollow Clock has no face, just an open space with an ...

The researchers use the analogy of a clock. Think of a normal clock with two hands: the hour hand and the minute hand. Now imagine the clock only has one hand. If it’s the hour hand, you can tell what ...