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Sensor Web: A look at an Internet in Physical Space: AR Orientation

Sensor Web: A look at an Internet in Physical Space: AR Orientation

The Sensor web, is a long-anticipated faced of an augmented world. It is, in theory at least, a huge web of interconnected sensors, actuators, RFID, GPS, specialised routing controls, and augmented sensory hardware, all wired together into an immense web in physical space.

The sensor web exists today, in a much more limited form - satellites and stratellites, Wi-Fi, mobiles and PDAs, seismic sensors, RFID and CCTV.

However, the modern sensor web is nowhere near full potential. In the near future, it will start to change into something far greater, truly allowing augmented reality

In 2008-2015, the sensor web is getting a huge shake-up. The European Galileo GPS satellite network will launch. The European network will complement the American one already up there. Both are compatible with one another, although separate systems, and will allow far greater GPS triangulation than ever before.

Additionally, the Russians are talking about reviving their own GPS system. If all three are up, then hopefully, by 2015, GPS will be precise enough to be down to the centimetre, anywhere on the planet. If so, do real-time kinematics becomes possible - ideal for augmented reality applications. Objects in motion will know precisely where they are.

Augmenting our World

The basic concept behind augmented reality is the superimposition of graphics, audio, and later tactile and aromatic sensory enhancements over the top of the physical world just as if the physical world was virtual.

Sensor-Net controlled Augmented reality - in particular, GPS and other positioning system controlled augmented reality interfaces orient on each individual's perspective.

Hopefully, by the end of this decade - 2010 at the latest -, we will see the first mass-marketed augmented-reality system, which one researcher calls "the Walkman of the 21st century."

What augmented reality attempts to do is not only superimpose virtual graphics/sounds/smells over a physical environment in real-time, but also keep those VR elements perfectly synced with the physical world elements also present. In other words an AR notice board stays in front of the same space of physical building wall, no matter how you shake and twist your head. What's more, as you walk towards or away from that notice board, it expands and contracts to fit the perspective.

Tracking and Orientation

In order to do this, the AR system must know the user's precise location, the building's precise location, and if any part of the notice board should be obscured by objects in between. It would not be a good thing if the AR was merrily displaying a notice board over the top of a car speeding towards you.

This is by far the greatest challenge facing developers of augmented reality. The necessity of knowing where the user is located in reference to his or her surroundings is paramount. There is also an additional problem in those annoying neck muscles and eyes of the average user - they tend to move them. A tracking system not only has to know where the user is physically, but also track the movement of users' eyes and heads.

A tracking system has to recognise these movements and project the graphics/sounds/smells/whatever related to the physical world environment the user is seeing at any given moment. Additionally, there is always a slight lag in AR sensory feedback, due to the tracking technology currently available.

In order to succeed, the next generation of augmented-reality systems will have to provide sensory feedback for each viewer's perspective. It will have to have minimal lag time, and where possible, anticipate needs just ahead of the user, to compensate where lag is unavoidable.

Coming full circle

For augmented reality to reach its full potential, it must have seamless transition between indoors and out. That means a tracking technology that can identify a user regardless of location. RFID may play a part; Wi-Fi or Wi-Max triangulation may too. The obvious candidate is GPS. However, Galileo is not up yet, and the US GPS network only has an accuracy of about 10 to 30 meters. Not bad if you are looking for a jet plane, bad if you are wondering where your hand is.

At the barest minimum a system measured in centimetres is needed. Millimetres would be much better, but that cannot be expected of GPS alone.

We need something better, something that takes data from many sources and triangulates.

We need the sensor web.

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