What could be cuter than a little robot that scuttles around its playpen and smiles all day? For the 2018 Hackaday prize [bobricius] is sharing his 2D Actuator for Micro Magnetic Robot. The name is not so cute, but it boasts a bill of materials under ten USD, so it should be perfect for educational use, which is why it is being created.
The double-layer circuit board hides six poles. Three poles run vertically, and three of them run horizontally. Each pole is analogous to a winding in a stepper motor. As the poles turn on, the magnetic shuttle moves to the nearest active pole. When the perpendicular windings activate, it becomes possible to lock that shuttle in place. As the windings activate in sequence, it becomes possible to move left/right and forward/back. The second video demonstrates this perfectly.
[bobricius] found inspiration from a scarier source, but wants us to know this is his creation, not a patent infringement. We are not lawyers.
Here is a way to visualize just what is happening with those FETs. Watch as a power lead is brushed across the terminals in order. With this kind of basic kit, students could learn the value of motor acceleration, deceleration, or launching little magnets at their classmates.