Although it may seem like science fiction, levitating objects is possible through acoustic tweezers which involves the shaping of ultrasound waves to manipulate objects, without any direct contact. Acoustic tweezers are capable of moving tiny objects like droplets, or biological cells, at any desired position.
Now, a recent study published in the Proceedings of the National Academy of Sciences (PNAS), demonstrated that acoustic levitation and manipulation of multiple objects could be done simultaneously. The researchers enabled efficient generation of sound fields that are complex enough to trap multiple objects at desired regions.
"We applied a novel algorithm that controls an array of 256 small loudspeakers -- and that is what allows us to create the intricate, tweezer-like, acoustic fields,” says Dr. Asier Marzo, from Universidad Publica De Navarra in Spain.
Researcher testing the acoustic traps generated by the Holographic Acoustic Tweezers
Image Credit: Sergio Larripa, Asier Marzo, Bruce Drinkwater © 2018 via University of Bristol
The study may inspire future advanced surgical applications involving acoustically stitching up internal injuries or delivering drugs to target organs.
"Now we have more versatility -- multiple pairs of hands to move things and perform complex procedures, it opens up possibilities that just weren't there before,” says Professor Bruce Drinkwater in the Department of Mechanical Engineering at the University of Bristol. "Optical tweezers are a fantastic technology, but always dangerously close to killing the cells being moved, with acoustics we're applying the same sort of forces but with way less energy associated. There's lots of applications that require cellular manipulation and acoustic systems are perfect for them."
Source: University of Bristol