Acoustic levitation

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Acoustic levitation is a method for suspending matter in a fluid by using acoustic radiation pressure from intense sound waves in the fluid. Acoustic levitation is possible because of the non-linear effects of intense sound waves.

Some methods can levitate objects without creating sound heard by the human ear such as the one demonstrated at Otsuka Lab,^[1] while others produce some audible sound. There are many ways of creating this effect, from creating a wave underneath the object and reflecting it back to its source, to using an acrylic glass tank to create a large acoustic field.

Acoustic levitation is usually used for "containerless processing" which has become more important of late due to the small size and resistance of microchips and other such things in industry.^[2] This method is harder to control than other methods of containerless processing such as electromagnetic levitation but has the advantage of being able to levitate nonconductive materials.

There is no known limit to what acoustic levitation can lift given enough vibratory sound, but currently the maximum amount that can be lifted by this force is a few kilograms.^[3] Acoustic levitators are used mostly in industry and for researchers of anti-gravity effects such as NASA; however some are commercially available to the public.

Contents 1 Trivia 2 References 3 External links 4 See also

[edit] Trivia

The video game Dark Cloud 2 has a field of science in the future called "aeroharmonics" which specifically is based on using sound to levitate an object like a vehicle. This may have been due to the fact that the science and applicability for small scale levitation would have already been in place by the time the game was in design.

[edit] References

1. ^ Ultrasonic Levitation. Retrieved on 2006-11-15.
2. ^ Michael Fitzpatrick. Sound Waves May Be Used To Generate Energy, Produce Weapons And More. Retrieved on 2006-11-15.
3. ^ Phenomena, theory and applications of near-field acoustic levitation (PDF). Retrieved on 2006-11-15.

[edit] External links

• Levitation and Flight in the Ancient World: A Modern Perspective
• McGraw-Hill AccessScience: Acoustic radiation pressure
• A Multi-Transducer Near Field Acoustic Levitation System for Noncontact Transportation of Large-Sized Planar Objects
• Honda Electronics: Ultrasonic levitation
• Live Science article with video
• [1]

[edit] See also

• Electrostatic levitation
• Magnetic levitation
• Radiation pressure
• Buoyancy