Whoa: Watch Scientists Use Sound Waves to Make Things Levitate

Wired.com, Kyle Vanhemert, January 2, 2014

Ahhh. University of Tokyo

With every new year comes change, and change can be scary. Thankfully, we know that there’s at least one way 2014 will be like every year that came before it. Watching scientists make stuff levitate is still cool as hell, same as it ever was.

The latest work comes from a group of researchers at the University of Tokyo. What we see in their latest proof of concept clip is fairly dumbfounding: Arrangements of tiny little beads lift into the air and glide around in perfect formation. An iron screw spins gently in space. Pieces of plastic, broken match heads, and even droplets of water all defy gravity, all thanks to the precise application of ultrasonic sound waves.

The idea itself is not entirely novel. As we’re told in the clip, scientists have been experimenting with acoustic levitation for decades, using sound waves to suspend materials in mid-air. What’s new here, though, is the ability to move those materials in three dimensions.

That’s made possible by the unique arrangement of the speakers themselves. Where former setups bounced sound waves off a solid plate, the Tokyo researchers instead use four panels of speakers, all facing each other. These walls combine to create an “ultrasonic focal point,” which can be moved—along with the object trapped in it—by adjusting the output from each speaker array. The sound waves are out of the range of human hearing, so the setup effectively operates in silence.

We’re already seeing similar technology used in clever ways. McLaren recently announced it’s doing away with windshield wipers, reportedly employingultrasonic vibrations to let its cars repel rain. Other obvious applications range from hoverboards to flying carpets. In the meantime, I’d be OK with 2014 being the year of funny animated GIFs of floating ants. Don’t let me down, science!