Check out this electromagnetic actuator, by Carl Bugeja, which opens a whole new realm of movement based on permanent magnets and an electronic circuit.
Consider how magnets work; attracting or repelling other magnets depending on how each is arranged. Electromagnets work in a similar manner. They’re traditionally made by wrapping wire around a metallic core. When electrified they create a magnetic field. Here Carl is demonstrating that those coils of wire can also be made out of flexible PCBs—no wrapping required. When electrified near a rare-earth magnet, they coil within the flexible PCB pushes away from the magnet.
The device is about the size of one’s fingertip, and if you need inspiration for what you could do with one (or many) be sure to check out the demo video below. The product listing has links to a few other pertinent videos as well, and his YouTube channel has lots of other electromagnetic experiments if you’d like to do a deeper dive into this fascinating subject.
More information on this build can be found on Hackaday.io, including Gerber files if you’d like to examine how it was made, modify the design, or even manufacture your own. While there are a multitude of things you could do with something like this, I can’t help but think that an electromagnetic propulsion system that progressively pushes a magnetic train around a track like an “unwrapped” stepper motor would be an especially interesting project. Carl’s most recent demo of the concept is a four-footed hopper that feels very much like an insect!
