Sonic Tractor Beam

[Dryson]

https://www.washingtonpost.com/news...eam-levitates-objects-using-only-sound-waves/


It looks like the Sonic Tractor Beam would be able to move small objects but larger objects would require turning the amps up causing a loud unpleasant noise.

 

[Asbo Zaprudder]

This thread also discusses the topic. Mind you, no one seemed to get too excited about that one.

The article you link states that larger objects require lower frequencies not larger amplitudes.

"The lower the frequency, the larger the object," Marzo explained. "So for instance if you want to levitate a soccer ball, the necessary sound waves will be dangerous for human hearing."

However, it doesn't state what range of size of objects can currently be levitated and moved. The linked paper quotes using expanded polystyrene particles ranging from 0.6 to 3.1 mm diameter.

There's also the laser version, of course:

http://www.iflscience.com/physics/p...r-tractor-beam-functional-over-long-distances

 

[Gingerbread Demon]

So could you make a real sonic screwdriver?

 

[Trekker4747]

So, a "sonic tractor beam" that cannot do most of the things a tractor beam can do? (Pull/tow objects.)