Scientists from the University of Bristol boasted that they forced to levitate the largest object in the history of development of acoustic beams-attractors. And even if this is just a polymer ball with a diameter of 2 cm, they are already making plans for human levitation. It's all about the new method, which was called the “ultrasonic tornado.”
Acoustic levitation with the help of attractor rays works very simply. At a strictly defined distance, two sound emitters are set up, from which the intersecting ultrasonic waves emanate. At this particular point in space a standing wave forms, within which the object can levitate.
The keyword “can” – you need to perfectly balance the characteristics of the target, otherwise the excess pressure from the acoustic waves will simply fling it away. Just this task was decided in Bristol, where they built a bowl with radiators located along its circumference. In its work, the “sound pattern” looks like a twisting spiral or tornado – the waves move around a stationary center in which the object levitates.
To prevent the ultrasonic tornado from spinning and throwing away the object, the system is equipped with a mechanism for switching the direction of the waves, so that they alternate and compensate each other's effects. This approach allowed to circumvent the restriction on the size of the object – now it can be much longer than the wavelength, which opens up prospects for levitation of really large and useful objects in the economy.js.src = “&version=v2.8”; 'script', 'facebook-jssdk'));