Scientists can levitate stuff and make it fly around using sound

Japanese scientists have made hundreds of tiny plastic balls float around like miniature spaceships.

Today’s news from the world of Awesome Science comes from the University of Tokyo, where a team has been levitating and controlling objects using sound. Here’s the video:

As the video points out at the beginning, levitation of objects using sound has been around for a few years. If you’ve ever stood in front of a large speaker you’ll know that they can pump out what feels like quite a forceful blast of air as they vibrate - but, somewhat deceptively, that’s not quite the whole story.

Rather than physically push air out from the speaker, what you’re experiencing is a wave of compression moving through the air. The speaker compresses a packet of air, which then “rolls” through the room, with the size of the compressed air corresponding the wavelength of the sound wave. And, just like sound waves, waves that overlap each other create new waves.

To levitate something just requires creating a standing wave. Think of it like this - if you’re watching a sound wave plotted out on a graph, it’ll be rolling along, going up and down as it oscillates. A standing wave occurs when two or more waves combine to create a new wave where, as the wave oscillates, there are points where there’s no movement. They’re called nodes.

Here’s a gif to illustrate how that works. The blue and green waves are combining to create the red wave, which has those points on the central axis that aren’t moving:

(Image: Wikimedia Commons)

If a speaker outputs a standing wave, in the most basic sense it means that it won’t feel like the areas of compression - those blasts of air - are moving. The gaps between those blasts of air will be positions of neutral force, with air pressure pushing in on it from both directions. If you stick an object in there that’s light enough, and smaller that the size the gap (which will be the sound’s wavelength), the force of the air should keep it floating in a stable position.

What the Tokyo University team has done is build upon that idea, by combining sound waves in three dimensions. The video shows not just tiny little plastic balls being levitated and controlled, but also resistors, LEDs, screws, bolts, and other small items. Rhett Allain at Wired worked out that you could levitate anything both smaller than 8mm and less dense than 1,000kg/m3, which is tiny - but it does have practical applications, particularly when people are working with sterile things they want to move but can't touch, like spaceship parts or medicines.

Ian Steadman is a staff science and technology writer at the New Statesman. He is on Twitter as @iansteadman.

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Connected - to save time, money and lives

Businesses and the public sector in the UK are increasingly exploring new ways they can work with the help of connected technology – and the benefits this will bring.

We live in a world that’s increasingly connected. EE was born three years ago and has spent this time creating one of the fastest and most reliable 4G networks in any country. The effect of this growth means more for the British population as a whole, along with its critical infrastructure and emergency responders, than it does for individuals and consumers.

Why? Mobility, according to analysts CCS Insight, is “the fulcrum of digital transformation”. In the short time that mobile networks have existed – and the even shorter and more profound growth arc of 4G – mobility has moved from being about faster speeds and more services on our phones to a whole new world of possibilities for the way we live and work.

The latest mobile technologies can make small companies look big. And, the experts warn, they can make big companies look unintentionally small.

Over 500,000 businesses in the UK use our network and services to increase productivity and save money. Much of the public sector uses it to save money too – and save lives. We’d like to walk you through the stories emerging from this new world – sharing some examples of what happens when workers, customers and machines become truly connected.

Connected Vehicle

Businesses in the UK have long treated their cars, vans and other vehicles as their mobile offices, workshops or command centres, whether for field engineers, sales reps or dozens of other roles. But it’s not always been easy. 

That’s changing. Take utility Northumbrian Water. It is responsible for 55,000km of pipelines, many in rural parts of the UK. It has found a solution in the Connected Vehicle service from EE that is based on transportgrade equipment. External antennae on a van connect to a ruggedised router that deals with extreme temperatures and can handle vibrations from road surfaces. 4G becomes a shared WiFi connection for workers and devices out in the field, increasing their efficiency significantly as workers can stay connected on site, rather than having to travel back to the office.

And is it effective?

“The business case writes itself,” said Alan Sherwen, head of IS service and operations at Northumbrian Water, which is now looking at a wider rollout.

Beyond the private sector, the public sector is throwing off its image as a technology laggard. Blue-light fire, police and ambulance services are doing more than just seeing the potential.

East Midlands Ambulance Service’s head of IM&T, Steve Bowyer, describes his experience with 4G’s “reliable, consistently fast data connections” as “quite transformational”.

The ambulance service knows that every second counts, especially when accidents occur in remote locations.

Bowyer calls the use of 4G-connected vehicles “an extension of our control room” – for example, 4G-equipped ambulances allow paramedics to send vital information to hospitals ahead of arrival.

And it’s a similar story with the police. Officers collect and submit evidence from the scenes of crimes and accidents. Staffordshire Police has started to use connected vehicles and more broadly estimates its 4G devices provide the equivalent of 250,000 additional hours of policing time on the beat each year. That’s the equivalent of 100 extra officers.

Rapid Site

The technology we’re talking about – fast, robust, often rural connectivity – isn’t always about being on the move. Industries such as construction that occupy a location sometimes for a matter of months are also employing high-speed, managed services to serve those on site.

Jackson Civil Engineering used to have to wait three months to get a line installed. It was holding back the business.

“The challenges I face are making sure the guys on site get connectivity and transmit information from laptops, mobile phones and tablets,” said Justin Corneby, the company’s IT manager. “If there’s no connectivity for our guys on the ground it almost stops them working completely.” Now setup at a new location takes under three days, and speeds tend to be up to 60Mbps where, before, a fixed line gave the company 8Mbps.

Housing association Green Square faces a similar challenge in its efforts to supply about 400 homes every year in the west of England.

Mark Gingell, ICT service manager at Green Square, said: “[We have] some challenges about how do we get our staff access to the internet. What we want is a seamless process for them to be able to log on and have the information at hand. The ultimate goal is to make great places where people can live.”

Public WiFi – in a box

Other types of business are on this connected journey too. Richardson’s operates 310 holiday boats on the Norfolk Broads and 4G Public WiFi from EE means not only coverage and simplicity for customers wanting internet access but knowing that compliance and online safety for families, through web filtering, is taken care of. In fact a whole range of businesses are now possible, many employing mobile payments systems which through their security and 4G connections open up a world of pop-up possibilities to businesses big and small.

Connected Health 

And lastly, the NHS is showing us that innovation can be built on even relatively simple technology. ‘Did not attend’ – or DNAs – cost the health service around £900m every year. That breaks down as £137 for every missed hospital appointment, £45 for each at a GP’s surgery. 

Intelligent messaging from EE means patients get a text message and simply reply to cancel or confirm an appointment. DNAs have been reduced by 67 per cent in one case, freeing up slots for others. That means there is the potential to save the NHS over £500m annually, just by improving the booking and scheduling service for patients with intelligent messaging. Meanwhile healthcare professionals get to target groups by demographics – for example, elderly people when it’s flu jab season. In short, this approach saves time, saves money and even saves lives.

Now you can

When we were the first to launch 4G in the UK, we had a simple message: Now you can. Most people took that to mean simply that smartphones, tablets, laptops and upcoming smart devices could get a faster network connection. But it’s been about much more than that.

Today, being connected in this way is a vital component for business and Britain’s vital public services. Our recent research of 1,000 UK businesses shows that 50 per cent of customers say 4G is critical to their business success. They report a 10 per cent uptick in productivity when adopting 4G – and gains can be greater in the public sector.

And we’re nowhere near finished. Now any organisation in the private or public sector can share in this connected story, employing new technology and innovative approaches as a managed service or in any way that best works for them. We are just as excited about the next three years as the last three.