The Physics of Lexus's Hoverboard
benonemusic writes: Lexus' hoverboard may never become commercially available, but is it scientifically feasible? You'd need to place a superconducting material in a magnetic field powerful enough to support the board and the rider. Steve Gourlay of Lawrence Berkeley Lab's Superconductor Magnet Group provides insights, including the possibility that Lexus put some very strong rare-earth magnets underneath the sidewalk in the video.
Magnetic levitation is certainly feasible, but it is almost certainly economically impractical.
For example, Ken Pence at Vanderbilt University has built a prototype magnetic levitation platform that uses spinning NdFeB magnets. I've seen it in action. It requires an aluminum sheet underneath the platform, and uses about 20 kW of power to lift a maximum of 300 pounds. Prof. Pence's ultimate goal is to make it steerable and have a demo with students driving it around a room.
However, Prof. Pence will cheerfully admit that the technology is far from practical for consumer use. You'd need to install aluminum sheeting under every roadway, and the power requirements for the amount of load being lifted are excessive. 20 kW is enough to push an electric car down the road at 60 mph. He will jokingly admit that his magnetic platform would only do 60 mph if you drove it off a cliff.
So why build it? His students constructed it as part of a Management of Technology course, where they learn firsthand the practical limitations of building a "gee whiz" device. I've seen some pretty interesting gadgets come out of that class (e.g. a wireless power transmitter), but as his students figure out, just because something is possible doesn't make it the least bit practical.
Points in case:
- Obviously supercooled.
- We do not get to see how much it dips with passenger. Hence it very likely only carries its own weight, which may be almost nothing.
This thing is no hover-board, it just looks like one. Levitating superconductors are nothing new. The only thing cool or noteworthy is the clever misdirection by Lexus.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.