While most of us spent the week trying to figure out which "Back to the Future II" prophesies came true, University of Navarre Ph.D. candidate Asier Marzo was busy publishing a paper about tractor beams.
Yeah, tractor beams.
In his article, published in the journal Nature, Marzo writes that sound can be used to levitate objects of different sizes and materials through air, water and tissue. "This allows us to manipulate cells, liquids, compounds or living things without touching or contaminating them," he explains.
Translation: According to the Washington Post, Marzo has invented a device that can "levitate tiny objects using only the power of sound -- a sonic tractor beam."
SONIC TRACTOR BEAM
The paper reports that the technology Marzo and his team have come up with could be used in a variety of ways, from building new touch screens "made of millions of moving, 3-D pixels" to one day using the beam to suspend and move "tiny structures inside the human body, clearing clots with ease." That could mean advances like moving microsurgical tools or drug capsules around in the body without making an incision.
Video courtesy Asier Marzo, Bruce Drinkwater and Sriram Subramanian via YouTube
Why go the sonic route? Marzo told the Post that magnetic levitation is cool but has limited reach, is hard to control and only a certain type of object can be mag-lev'd. Optical levitation is also an option, but it's kind of weak and quantum levitation is even weaker. "Using sound waves has several advantages," Marzo said. "Sound waves have the best ratio of input power to exerted force. Sound can travel through air, water and human tissue."
The paper gave the example of a stereo speaker. If you put some liquid on the speaker cone and crank it up, you can literally see the force of sound waves make the water bounce. Marzo's tractor beam would be similar: You "just need to tune the super-strong sound waves so that they support the object you want supported."
The Technology Isn't That New
According to the Post, NASA has been using sound levitation since the 1960s to create "artificial gravity for experiments." This new version doesn't require you to completely surround an object with speakers, but instead uses "64 miniature loudspeakers at the base of the object ... to create high-pitched and high-intensity sound waves," which create a force field strong enough to levitate objects smaller than one millimeter. So not, like, a human being yet, but you have to start somewhere, right?
There is one drawback. You need way lower frequencies to float larger objects. "So for instance if you want to levitate a soccer ball, the necessary sound waves will be dangerous for human hearing," Marzo said.
For now, Marzo and his team are focusing on working with an outside tech company to create a new generation of touch screens that could be on the market in five years or less. "This would enable the development of 3-D displays composed of millions of levitating particles that act as tangible pixels," he said.