Sonic ‘tractor beam’: Engineers develop device to ‘manipulate objects’ &‘defy gravity’

© University of Sussex
The same sonic tractor beam which flying saucers are equipped with in movies has been developed in real life by a group of engineers who say the prototype device can pull, push and generally manipulate objects using ultrasonic waves.

A new system that creates “sound holograms” in midair and traps objects inside, keeping them from falling, has been designed by a group of researchers from the Universities of Bristol and Sussex, in collaboration with Ultrahaptics, sciencemag.org reports.

“In our device we manipulate objects in mid-air and seemingly defy gravity,” said Sriram Subramanian, Professor of Informatics at the University of Sussex, comparing the technology to the “beam effect” shown in Star Trek or Star Wars movies, according to the University of Sussex official website.

The results of the experiment have been published in Nature’s Communications journal. The article describes the testing procedure: 64 mini speakers were used to create high-intensity sound waves that generate an acoustic hologram suspending a 4mm-wide polystyrene ball in space.

“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,” the lead author Bruce Drinkwater, a mechanical engineer at University of Bristol in the United Kingdom, told Live Science. “It's a question of harnessing that force.”

“It’s hard to get across how many times we tried and failed,” he said, looking back on countless number of failed attempts to make particles levitate.

“You’ve got this array of loudspeakers and you’re continually popping particles where you think they should levitate, and then watch them continually drop down.”

The team hopes the new technology will come in handy when dealing with particularly delicate materials or tissues. For example, the device may be used by construction workers to arrange items when touching them is not an option. Surgeons may also make use of it once the technical process is perfected.

“My main target for the future is in vivo levitation,” Asier Marzo, computational engineer at the University of Bristol, said.

Ultrasonic waves featured in the tractor beam are believed to be relatively harmless to human body so the device may be used for removing kidney stones or clots, delivering drugs to particular organs and performing microsurgical operations.

Scientists have long been trying to master the skill of levitation with a several similar devices. One of them, which only operated with water, was introduced by the researchers from the Australian National University in Canberra in 2014. The “water” beam promised to find new solutions to oil spills and ways to rescue malfunctioning ships.