A photo from open sources
Employees of the University of Tokyo and the Institute of Technology Nagoya succeeded in driving small objects with the help of complex acoustic levitation systems: sound waves moved particles polystyrene with a diameter of 0.6 to 2 mm in three-dimensional space. Previously, objects using the same system could only be moved in two dimensions. To move water droplets through the air, polystyrene particles, small pieces of wood and even screws, it took four rows of speakers. These objects moved in all directions to the extent permitted by the conditions experiment. The movement in this case is caused by standing ultrasonic waves. The literature describes the experience that can be produce at home: placing over ultrasound with a generator, a strip of paper in your hand so that its free the end was located 3-5 mm above the end of the rod, you need to click on generator button – and the tip of the paper under the influence of a sound wave goes up and hangs motionless above the rod. Apparatus used in the experiment, much more complicated than the generator: sound waves with a frequency of over 20 kHz that are not audible to the human ear, come from four sides and intersect within the bounded space. Thus, they form a movable focus, in which a small object, as it were, clamps and freezes in space. The direction of the waves can arbitrarily change, while the object moves around. Sound levitation – a way to overcome the earthly attraction, scientists say. Therefore, devices for Acoustic levitation is used by organizations such as NASA.
Levitation Japan
