|arya||Date: Thursday, 29-October-2015, 9:02 PM | Message # 1|
|It may seem straight out of "Star Trek," but it's real: Scientists have created a sonic "tractor beam" that can pull, push and pirouette objects that levitate in thin air.|
The sonic tractor beam relies on a precisely timed sequence of sound waves that create a region of low pressure that traps tiny objects that can then be manipulated solely by sound waves, the scientists said in a new study.
Though the new demonstration was just a proof of concept, the same technique could be adapted to remotely manipulate cells inside the human body or target the release of medicine locked in acoustically activated drug capsules, said study co-author Bruce Drinkwater, a mechanical engineer at the University of Bristol in the United Kingdom. [Watch the Tractor Beam Levitate Objects]
In the past, scientists have used everything from laser beams to superconducting magnetic fields to levitate objects. And in 2014, researchers at the University of Dundee in Scotland showed that acoustic holograms that act like a tractor beam could theoretically suck in objects.
"They really just showed the force was there; they weren't able to grab or pull anything," Drinkwater said.
The principle behind the new system is simple: Sound waves, which are waves of high and low pressure that travel through a medium such as air, produce force.
"We've all experienced the force of sound -- if you go to a rock concert, not only do you hear it, but you can sometimes feel your innards being moved," Drinkwater told Live Science. "It's a question of harnessing that force."
By tightly orchestrating the release of these sound waves, it should be possible to create a region with low pressure that effectively counteracts gravity, trapping an object in midair. If the object tries to move left, right, up or down, higher-pressure zones around the object nudge it back into its low-pressure, quiet zone.
But figuring out the exact pattern of sound waves to create this tractor force is difficult, scientists say; the mathematical equations governing its behavior can't be solved with a pen and paper.
Read more/full article/source - http://www.cbsnews.com/news....d-waves