When Lexus showed off its new hovering creation back in June, we were all ready to don a red vest, channel our inner McFly, and hop on. It wasn’t the first experimental hoverboard we’d seen, but it was definitely one of the better-looking.
In a new video, the team behind the gliding gadget has taken us deeper into its mechanics, explaining the science behind the board – and just as we suspected, it all has to do with magnets.
The Lexus board’s successful levitation relies on magnetic fields: one expelled by a chilled superconductor (yttrium barium copper oxide, or YBa2Cu3O7) within the board, and one generated by a magnet-filled track beneath it. You can’t see anything with your eyes, but the field is visible with the help of a penny.
“We can feel it with magnetic materials,” explains professor Ludwig Schultz. “You have north, south, and north again. And in between, you have a magnetic field that sits above the track. When you bring the board above the track, and cool it down with liquid nitrogen, the compound within gets its superconducting properties, and stores the magnetic field, and is able to levitate as long as it stays cool.”
Superconductors — materials that can conduct electricity without resistance — hate magnetic fields. Depending on the kind of superconductor, a magnetic field in its presence will either be completely expelled from the superconductor’s interior, or will pierce it with small magnetic vortexes. It’s this “flux pinning” that keeps a super-cooled superconductor above a magnetic field, like in this viral video. The board is a pin cushion of superconductors sitting atop magnetic needles.
It’s the interaction between these fields that pins the board mid-air. This “quantum levitation” is a known phenomenon, and nothing Lexus themselves discovered (it wasn’t even the first hoverboard to use this phenomenon), but what they have done is develop a way to stabilize it along a complicated track with ups, downs, twists, and turns.
“We thought, ‘maybe they’ll want a ten-meter track, and this can all be done, and it will be easy,’ but then, when I saw these plans for jumping and other things, it became a tough job,” recalls Schultz. The team had to adjust both track and board, to compensate for any added stress. “We started with [perfecting] inclines, then bended curves… it’s a really amazing project. We hope to inspire people with this. Nothing is impossible.”