Nav: Home

Using sound to independently levitate a range of objects is achieved for the first time

December 19, 2018

This research, which has been funded by the Engineering and Physical Sciences Research Council (EPSRC) in the United Kingdom, has just been published in the scientific journal Proceedings of the National Academy of Science, the official publication of the National Academy of Sciences of the United States.

Sound can exert force on objects. When ultrasonic waves are used and when the volume is increased considerably, scientists can create an acoustic field capable of moving a whole range of small-sized objects. The new algorithm developed by the team of researchers enables sufficiently complex acoustic fields to capture numerous objects in the desired positions.

Advantages of acoustic tweezers

These acoustic tweezers have capabilities similar to those of the optical tweezers that won the Nobel Prize in Physics this year and which use lasers to capture and transport microparticles. Yet acoustic tweezers offer various advantages over optical tweezers.

Lasers can only travel through transparent mediums, which makes it complicated for them to be used in applications inside biological tissue. By contrast, ultrasound is routinely used in pregnancy ultrasound scanning and in treating kidney stones, as it can penetrate tissue safely and non-invasively.

Another advantage is that acoustic devices are 100,000 times more efficient than optical systems. "Optical tweezers are a fantastic technology, but they always come dangerously close to killing the cells they manipulate. By contrast, the acoustic version enables us to generate forces with the same magnitude but with much less energy. There are many applications that call for cell manipulation, and acoustic systems are perfect for that," pointed out Prof Drinkwater, lecturer in the Department of Mechanical Engineering at the University of Bristol.

To demonstrate the precision of their system, the scientists stuck two millimetre-sized spheres to the ends of a thread and used the acoustic tweezers to "sew" the thread into a piece of fabric. The system can simultaneously control the 3D movement of up to 25 particles in the air. The team hopes that the technique could be adapted to the manipulation of particles in water within approximately one year. Shortly afterwards, it could be adapted for use in biological tissue.

"The flexibility of the ultrasound waves enables us to operate on micrometric scales to move cells within printed 3D structures or living tissue," explained Asier Marzo. "But we can also work on a larger scale, for example, to levitate tangible pixels that form various objects in the air." These objects comprising levitating particles that can be observed by several people from different angles are also susceptible to being touched and manipulated directly; in other words, one can use one's hands to drag them. "We are used to two-dimensional pixels enclosed in our monitors, but we would like to see a technology in which objects are made up of tangible pixels that float in mid-air," added the researcher in the Department of Statistics, Computing and Mathematics of the Public University of Navarre.
-end-


Elhuyar Fundazioa

Related Ultrasound Articles:

Ultrasound imaging of the brain and liver
Ultrasound is commonly used in diagnostic imaging of the body's soft tissues, including muscles, joints, tendons and internal organs.
Ultrasound for children with abdominal trauma
Despite evidence showing that the routine use of sonography in hospital emergency departments can safely improve care for adults when evaluating for possible abdominal trauma injuries, researchers at UC Davis Medical Center could not identify any significant improvements in care for pediatric trauma patients.
New approach uses ultrasound to measure fluid in the lungs
A team of engineering and medical researchers has found a way to use ultrasound to monitor fluid levels in the lung, offering a noninvasive way to track progress in treating pulmonary edema -- fluid in the lungs -- which often occurs in patients with congestive heart failure.
Optical generation of ultrasound via photoacoustic effect
Limitations of the piezoelectric array technologies conventionally used for ultrasonics inspired researchers to explore an alternative mechanism for generating ultrasound via light (the photoacoustic effect).
New method to detect ultrasound with light
A tiny, transparent device that fits into a contact lens can determine the speed of blood flow and oxygen metabolic rate at the back of the eye, helping to diagnose diseases such as macular degeneration.
More Ultrasound News and Ultrasound Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Anthropomorphic
Do animals grieve? Do they have language or consciousness? For a long time, scientists resisted the urge to look for human qualities in animals. This hour, TED speakers explore how that is changing. Guests include biological anthropologist Barbara King, dolphin researcher Denise Herzing, primatologist Frans de Waal, and ecologist Carl Safina.
Now Playing: Science for the People

#534 Bacteria are Coming for Your OJ
What makes breakfast, breakfast? Well, according to every movie and TV show we've ever seen, a big glass of orange juice is basically required. But our morning grapefruit might be in danger. Why? Citrus greening, a bacteria carried by a bug, has infected 90% of the citrus groves in Florida. It's coming for your OJ. We'll talk with University of Maryland plant virologist Anne Simon about ways to stop the citrus killer, and with science writer and journalist Maryn McKenna about why throwing antibiotics at the problem is probably not the solution. Related links: A Review of the Citrus Greening...