Researchers Show That Ultrasound Can Levitate Large Objects

Scientists have long dreamed of using acoustic levitation to float objects. Researchers in Brazil and the UK have successfully levitated a polystyrene ball 3.6 times larger than the ultrasonic waves holding it up. The trick was to create a standing wave in the gap between the transducers and the object, instead of the usual pressure node between the transducer and a reflector. You can change the angle and number of transducers without messing with the effect, and it finally creates both horizontal and vertical lift -- you don't need physical support to prevent the object from drifting sideways.

"Acoustic levitation of small particles at the acoustic pressure nodes of a standing wave is well-known, but the maximum particle size that can be levitated at the pressure nodes is around one quarter of the acoustic wavelength," Andrade told "This means that, for a transducer operating at the ultrasonic range (frequency above 20 kHz), the maximum particle size that can be levitated is around 4 mm. In our paper, we demonstrate that we can combine multiple ultrasonic transducers to levitate an object significantly larger than the acoustic wavelength. In our experiment, we could increase the maximum object size from one quarter of the wavelength to 50 mm, which is approximately 3.6 times the acoustic wavelength."

Although there are several different ways to acoustically levitate an object, most methods use an ultrasonic transducer, which converts electrical signals into ultrasonic waves. The current setup uses three ultrasonic transducers arranged in a tripod fashion around the sphere.

As the researchers explain, the angle and number of transducers can be changed, and this does not interfere with the setup's ability to levitate a large object. The ability to levitate the large sphere occurs because the three transducers produce a standing wave in the space between the transducers and the sphere. In previous methods, small objects are levitated by being trapped at the pressure nodes of the standing wave, but this is not the case here.


The technology only works with stationary objects at the moment. Sorry, folks, you won't see ultrasonic hovercars any time soon. Levitation that can manipulate large objects is on the cards, though, and it shouldn't be limited to specific shapes or sizes. You could eventually see this used to hold on to liquid in space, or to study very hot objects (say, molten metal) that you wouldn't dare touch.

source:, Applied Physics Letters,

The owner of will not be liable for any errors or omissions in this information nor for the availability of this information. The owner will not be liable for any losses, injuries, or damages from the display or use of this information.Report any Broken Download linkon Blogmytuts Facebook Page. IF YOU WANT TO BORROW MY CONTENT PLEASE CONTACT US..
Share on Google Plus

About Jaime Lacson

A Freelance Computer Tech with knowledge about computer, router and mobile phones, especially in Upgrade and Downgrade OS, Software and Hardware troubleshooting. follow me at Google+
    Blogger Comment
    Facebook Comment