Brian Haidet Puts Electricity to Work Finding the Shortest Route Through a Maze
Using a maze laser-cut from aluminum, a power supply, and a thermal camera, electricity can solve a maze — all by itself.
Materials scientist Brian Haidet, PhD, has drafted an army of electrons to solve a maze — smartly printed using aluminum foil and taking advantage of electrical flow's desire to find the path of least resistance.
"The average flow of electrons in all these little bits of foil is following precisely the correct shortest path from the start to the finish of the maze," Haidet explains of his demonstration. "We can't actually see electrons flowing in metals with our eyes, [so we] look at it with a thermal camera. The electric current dissipates its energy as heat inside of the foil maze, and the black spray paint makes an excellent high-emissivity surface — so we can see the infrared radiation on camera."
Haidet's experiment was inspired by earlier work by Steve Mould on solving a maze using pressurized water. Rather than the flow of water, though, Haidet's maze is solved through the flow of electrons — and took a little building. First, the maze shape was traced as a vector in an illustration program, then laser-cut out of a sheet of aluminum foil spray-painted black on one side. The start and the end of the maze were connected to a power supply, and the flow of electrons observed through the heating of the metal.
Effectively, Haidet turned the maze into an resistor, inductor, and capacitor (RLC) circuit. "The thin bits of foil behave like capacitors and store some electrons using electric fields," Haidet explains, "and the magnetic fields around the input wires are coupling to this and making it bounce."
While the maze is technically only solved on average — "some current is still taking the long route," Haidet admits, "but it's not very much, and it really doesn't show up in the thermal camera" — it's enough to highlight the fastest route, though whether you can laser-cut and assemble the maze before someone else could solve the printed version with a pen is questionable.
Haidet's full video, with an explanation of the physics behind the project and a water-based demonstration, is available on his YouTube channel, AlphaPhoenix.