Electronics

SoundBender levitates objects by curving sound waves around obstacles

SoundBender levitates objects by curving sound waves around obstacles
SoundBender is an acoustic levitation device that can bend sound waves around obstacles
SoundBender is an acoustic levitation device that can bend sound waves around obstacles
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SoundBender is an acoustic levitation device that can bend sound waves around obstacles
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SoundBender is an acoustic levitation device that can bend sound waves around obstacles
SoundBender is made up of a combination of a phased array of transducers and acoustic metamaterials
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SoundBender is made up of a combination of a phased array of transducers and acoustic metamaterials

Levitation is often thought of as the realm of magicians or The Jetsons, but it is technically possible. That said, the tech seems to be moving pretty slowly. Now, researchers at the University of Sussex have developed SoundBender, a technology that bends sound waves around obstacles to acoustically levitate objects above them.

The SoundBender is a hybrid system, combining phased arrays of transducers (PATs) and acoustic metamaterials. PATs are made up of a series of small transducers that each give off pulses of ultrasound waves, which can be directed by changing the order they pulse in. These are arranged in a rectangular plate, above which sits a circular metamaterial designed to guide the sound waves up and around, creating a "hollow" space in the middle.

This combination allows small objects to hover above obstacles placed in the center of the sound field, which the team demonstrated by levitating a particle over the top of a Lego figure. The process could also be used to generate haptic feedback when someone places their hand in the beam, or to move non-solid objects – controlling a candle's flame, for example, or moving clouds of particles to create visible "holograms."

SoundBender is made up of a combination of a phased array of transducers and acoustic metamaterials
SoundBender is made up of a combination of a phased array of transducers and acoustic metamaterials

"This is a significant step forward for ultrasound levitation and overcomes a significant drawback that has been hampering development in this field," says Gianluca Memoli, co-creator of SoundBender. "We have achieved incredibly dynamic and responsive control, so real-time adjustments are just one step away."

As for what you might one day be able to do with this technology, the team has a few ideas. SoundBender could be put to work in interactive museum displays, directing smells from diffusers to targeted spots or rooms, or sculpting shapes out of fire or fog. That last bit sounds like it begins to cross over with the team's previous work in fog screens like MisTable and MistForm.

"Following our breakthrough, the potential now is for a device that can bend around larger objects, potentially even as the obstacle is moving," says Sriram Subramanian, co-creator of SoundBender. "We are also pursuing how to make the device broadband so it can work for all frequencies of sound. This would allow, for instance, sending the music of a radio behind a corner or creating zones of silence in the middle of a dance floor."

The research was presented at the ACM User Interface Software and Technology Symposium in Berlin this week.

Source: University of Sussex

SoundBender: Dynamic Acoustic Control Behind Obstacles

2 comments
2 comments
Brian M
Probably the most useful application would be the bending of sound sources to create zone of silence. Hope the ultrasound frequency is high enough otherwise danger from very irritated dogs!
Kalavo
Use this to contain the fision ring in ITER power plant.