Discovery Of New Acoustic Tractor Beams Could Levitate Large Objects Including Humans


Scientists discovered that new acoustic tractor beams could levitate large objects and humans. The discovery could also lead to the development of drug capsules or micro-surgical implements within the body.

The description of the discovery was published in Physical Review Letters. The research was led by scientists from the University of Bristol. The acoustic tractor beams utilize the power of sound, which are rapidly fluctuating, that could hold the particles in mid-air and hover. The beams could grab most solids or liquids. These acoustic vortices are just like tornadoes of sound that are made of a twister-like structure with a loud sound surrounding the silent core, according to

In the study, the scientists who are engineers used ultrasonic waves at a pitch of 40kHz to fabricate the acoustic vortices. They held a two-centimeter sphere, which is made of a synthetic polymer, in the tractor beam.

The team found that the rate of rotation could be managed by swiftly altering the twisting direction of the vortices that balances the tractor beam. Then, they augment the size of the silent core, which enables it to hold the larger objects. The scientists said that the acoustic tractor beams could levitate large objects using this process in the future, according to University of Bristol press release.

Dr. Asier Marzo, the lead author of the research, said that the discovery of acoustic tractor beams could open doors to many new applications. She further said that acoustic researchers had been frustrated by the size limit for years, so it is satisfying to find a way to overcome it.


Meanwhile, Dr. Mihai Caleap, a senior research associate, who created the simulations explained that more acoustic power could be possible to hold even bigger objects in the future. He further explained that this was only thought to be possible using lower pitches, making the experiment audible and dangerous for humans.

Scientists and engineers have long been fascinated with tractor beams, which could attract an object from a distance. In the past, the concept of tractor beams had been utilized in some programs such as Star Trek. The tractor beams worked in Star Trek by allocating an object in the focus of a subspace interference pattern, which was generated by two beams from an emitter.

The object was drawn along with the interference pattern once the beams were controlled properly. Then, the object moved toward or away from the emitter by altering the action of the beams. In this new research, the scientists have created acoustic tractor beams that use high-amplitude sound waves to pick up and move large objects.