These tiny particles are being lifted with sound — no magic tricks required! Scientists have harnessed the physical force of sound waves before, but for the first time acoustic levitation has been successfully used on multiple objects independently.
The breakthrough was achieved by Asier Marzo Pérez of the University of Navarra in Spain and Bruce Drinkwater of the University of Bristol in the United Kingdom. Their results were published in the journal Proceedings of the National Academy of Sciences.
The researchers developed a new algorithm that uses an array of sound emitters to create an acoustic field complex strong enough to trap multiple objects, like these one millimeter plastic beads.
They imagine the system being used to create mid-air displays using physical pixels, and “acoustic tweezers” that can be used for noninvasive surgery, noting “acoustic devices are 100,000 times more efficient than optical systems.”
The current experimental setup can simultaneously handle 25 tiny particles in 3-D space. It’s precise enough that the scientists were able to attach a thread to two of the spheres and “sew” it onto a piece of cloth using nothing but sound. They hope to be able to adapt the technique to use in water over the next year.