The year 2015 is here! Seriously, anyone who has watched Back to the Future would instantly recognize it as the year that Marty McFly finally uses the ever iconic hoverboard. The sad news, however, is that 2015 just isn’t the future the movie wanted it to be, and even the hoverboard itself is still something that is quite far away from our current technology’s reach…
Or is it?
Lexus recently unveiled its newest promotional stunt, which features a hoverboard that is strikingly similar to the one used in the movie. What’s even more exciting is that, unlike most other hoverboard publicity stunts and gimmicks during the past months, this one is functional and working! The hoverboard floats in midair, and it can be used to propel forward intuitively just as you would a regular skateboard.
But how in the world does it work, and can we recreate the technology ourselves? To answer that question, you must first understand the concept of superconductivity. Superconductivity is a special property of matter that allows it to exhibit perfect zero electrical resistance and repulsion to magnetic fields when cooled below a certain critical temperature point. Unlike normal magnets that create an oscillating magnetic field, the superconductor redirects the field around itself via the Meissner effect. This effectively creates an expulsive reaction to any magnetic field, regardless of orientation. Because of this, the concept has been used, for a long time, to develop new ideas for alternative methods of propulsion and transportation.
As you might have already noticed from the commercials, “smoke” is coming out of the hoverboard. Well, the entire thing is being supercooled down to about -321 degrees Fahrenheit (-196 degree Celsius) using liquid nitrogen, which is the “smoke” that you see being vented out. At this low temperature, the hoverboard interacts with the custom-made track and ground so that it creates a perfect levitating effect, just as any superconducting material would. The user can then tread on the area and push it around with ease, since it will not touch the ground as long as it is oriented upright.
So, to recreate the technology, you need to cool a material down to its transition temperature, and then place it in a magnetic field, or on a surface that is capable of exhibiting magnetic properties. You probably need to prepare a huge and wide metallic surface, or something similar, for you to have a ground to play on. By itself, it should float on such surfaces, regardless of orientation. However, if you want it to be used and designed like a hoverboard, you also need to consider balancing yourself onto it so it doesn’t tip over at the sides.
In addition to surface orientation and balancing, there is also the problem of ‘refueling’ the hoverboard with liquid nitrogen since it needs to be kept at supercooled temperatures. On that hot day in Catalonia, Spain, where the Lexus hoverboard was showcased, it took about ten minutes to use it before it needed to be refilled again in about the same time. It might last longer during colder seasons, but you still won’t be able to enjoy playing with it for an entire afternoon.
To make a long story short, the Lexus hoverboard may well not be worth recreating, but it’s a very nice touch to the concept; plus, it’s very feasible if you just want it to work. The company had the leisure of simply introducing the item in a promotional video, though, so they never really have to worry about using the hoverboard like a normal skater would.