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Smart Special - Smart Dust

Surface-to-surface sensors are now linking up for the ultimate ‘surveillance and control’ network.

How smart can a city be? Could it tell you where to park your car? Could it guide your car to a vacant space by communicating with your sat-nav system? And is it smart enough to inform you of how many eco-brownie points you have earned by following its advice?

All these things are feasible in a smart city model, but for these technological metabolisms to work they need some sort of tiny endpoint monitoring device, probably MEMS (microelectromechanical systems) based, that will feed back the basic information about what is happening on the ground - or in the air - 'eyes', 'ears', and 'noses', in effect, that will feed back the basic information.

The electronic sensors that would monitor the parking spaces and traffic in the city, tell you what the air quality is like, or be alert to the sound of breaking car window glass in the event of a theft, are already beginning to appear. In the city of Santander in northern Spain the SmartSantander project has started a trial of parking sensors, with plans to extend the work to other testbeds in other European towns and cities such as Guildford in the UK and Lübeck in Germany.

Developed by Libelium, the sensors are packed into a can and buried in the tarmac, using the changes in a magnetic field caused by a car chassis to detect whether each parking space is occupied or not. When a car pulls in or moves away, the sensors use the ZigBee low-power wireless standard to send a message to relays mounted on streetlamps, which then pass the data to a central computer.

The notion of detecting passing vehicles was how the concept of so-called 'smart dust' - small, unobtrusive electronic sensors spread across the landscape - had its beginnings at the end of the 1990s.

University of California researcher Kris Pister proposed to the US Defense Advanced Research Projects Agency (DARPA) the idea of aircraft scattering lightweight sensors in much the same way they have dropped bags of paper propaganda in the past. Tiny sensors, each one powered by a hearing-aid battery, would listen out for vehicles as they passed in the night, and then relay that information to military commanders back at base. Pister envisaged they could even be dropped onto vehicles by small self-guiding or remote-controlled drones, and then provide information about their movements.

In the peacetime environment, meanwhile,'many of the necessary sensors are already in place. New cars already have their own GPS-assisted sat-nav systems, many of which are configured to receive data wirelessly so that they can keep maps up to date or obtain real-time data on congestion. By being automatically connected to the Internet, each sat-nav becomes a tiny component in a massive congestion analyser. There is no need for external sensors to detect road conditions because the cars themselves report where they are and at what speed they are moving. Even if only a fraction of cars on a motorway have such a GPS, the fact that a group of them along a stretch report a speed of 10mph quickly signals that something may be affecting road conditions.

Data capture

Capturing this real-time data and acting on it is part of the European Commission's strategy for bringing European countries back into the computing industry. European technology companies have been relatively successful in selling mobile and embedded systems - computers inside small pieces of equipment. At the Design Automation and Test in Europe conference earlier this year, Rolf Riemenschneider, research programme officer for embedded systems and control at the European Commission, declared that: "We see not just an explosion of data, but an explosion of real-time online data."

When attempting to assess how new connectivity paradigms might be adopted it is important to understand the importance of the 'drip' effect. The so-called 'internet of things' does not need to happen in one huge technology upgrade. The sensors are appearing in niche applications here, there and everywhere, but will gradually link together into much larger network fabrics that use information from many different self-powered sensors to reveal more about the movements and activity of the population.

Sensors deployed for one purpose or application could very well be re-oriented for quite different uses as the technology progresses. "The world becomes a global 'system of systems, where the Cloud meets the embedded world," adds Riemenschneider.

As with traffic automation, it may not be major projects that drive the rise of the smart dust-powered internet of things, but the interconnection of small-scale systems in the home. Andy Stanford-Clark, CTO of smart energy technologies at IBM, explained at the recent Future World Symposium organised by the National Microelectronics Institute (NMI) how he has equipped his home on the Isle of Wight with an array of sensors. His aim is to cut energy usage; the sensors provide him with the raw data he needs in the form of graphs generated by a home server. The graphs show which parts of the house consume most of the bought energy. Like most houses, heating is a big consumer. But the strips of halogen bulbs in the kitchen used to be a large contributor to the overall bill. "It was costing £148 a year to light the kitchen. This information made the case for switching to LED lighting very easy," reports Stanford-Clark. "It will pay for itself within two years."

A community of energy savers has developed at the IBM research park where Stanford-Clark works: "People keep going back every day to see who is winning," he says.

The competitive element stops the distributed sensor and monitoring system, at least at this particular office, from becoming an 'RTD' (return to drawer) technology, in Stanford-Clark's view. "People's interest stays high," he claims.

"I am absolutely fascinated by this data," Stanford-Clark confesses, stressing that he does not expect others to have the same love for monitoring graphs of home energy usage: "I built a sphere with red, green and blue LEDs in it. It can save you a fiver a night in terms of overnight consumption simply by paying attention to the orb."

With the right user interface, it should be possible to extend such detailed energy monitoring to everyone. Stanford-Clark has helped the Chale project on the Isle of Wight, which is meant to bring households out of fuel poverty by making smarter use of renewable energy. "The aim of the project was to find out if residents would use free energy," Stanford-Clark explains.

People enrolled in the project have access to free energy generated by solar panels and wind turbines, among other sources, only paying if their consumption exceeds the capacity of the renewables. "If you have a washing machine and a tumble drier going at once, for example, only one will be paid for by the sun," says Stanford-Clark. "Anecdotally, we are finding that energy bills are being roughly halved, and that rent arrears have also gone down."

The next step is to work out whether the anecdotal evidence is right. The University of Surrey is working on a quantitative study to work out the savings across households in the project and should report later this year. If the research does show that the increased data leads to better use of energy, it would be a big step towards the 'Eco Island'.

Water we want

Indirectly, the distributed-sensor technology also watches for potential emergencies. The water-meter monitor, for example, will send out a message if it spots either a large amount of water being used within a short space of time, or constant usage for too long a period. Either could be a herald of an accidental home flood, and the former happened when the hosepipe and its valve were dislodged on one occasion.

"The good news was that it was only in the garden and a neighbour was able to sort it out," Stanford-Clark says. In the loft, meanwhile, Stanford-Clark has installed electronic mouse traps. "Once a trap has gone off, it doesn't catch any more mice. So you want to know as quickly as possible if a trap has caught one. The trap sends a message when it's triggered: a 'mouse event'," he explains, with a puckish nod to computer programming jargon.

The sensor proliferation could go a lot further just within the home, as well as offices and factories, says Stanford-Clark: "You can use pressure sensors to detect where people are. And then use that to optimise heating and lighting."

Building automation - rather than transport - is where much of the commercial activity is now concentrated. It is also one of the reasons why chipmaker Linear Technology bought Pister's company Dust Networks late last year. Pressure sensors in the floor can detect people moving around a building, and turn lights on and off automatically so that empty areas are not kept lit. More widespread temperature sensors can help optimise heating and help track down the sources of fires in large buildings. All good stuff - but the sensors can go further.

Dust of surveillance

No-one is yet clear on how well these systems will keep pace with the data deluge; but there is a potentially bigger issue: the social problem. How will people react to being tracked in real-time every minute of the day even if it ostensibly being used to save energy or guide them to an appointment? Jeremy Bentham's Panopticon design was envisaged as the perfect prison - one in which the warders could keep an eye (and an ear) on inmates at all times. But this digital panopticon, so to speak, is being built for a population that ostensibly has committed no crimes.

The European Commission has admitted that it has no legislation in place that can adequately protect the privacy of people in this future, having only just updated the existing legislation at the start of the year.

In the spring of 2012, the European Commission launched a consultation programme to work out how to update the extant Data Protection Act to cope with the Internet of Things. The first step is a survey to try to work out how much privacy people will give up to support aims such as greater energy efficiency and what safeguards might be needed. Given the rate at which multinational online corporations such as Facebook and Google have acquired massive quantities of data on the population, the question is whether Europe and national governments can update their laws quickly enough to make a difference. *

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