[From New Scientist, where the story includes a 1:51 minute video]
Virtual traveller: Beam a live, 3D you into the world
Thanks to a virtual reality and telepresence mashup, you no longer have to travel the globe to visit friends or wander around ancient ruins
11 April 2013 by Catherine Brahic
Magazine issue 2912
One day, I’ll play hide and seek with my niece. I’ll turn around while she hides, and later, a flash of purple cotton will make me peer over the log she’s hiding behind. It sounds pedestrian, except I will be in London, Lucie will be 7800 kilometres away, and we will be playing together in a virtual jungle.
The virtual reality (VR) system that will make my fantasy possible is sitting in a lab at the Bauhaus University in Weimar, Germany. It combines 3D glasses and a hack of Microsoft’s Kinect to allow the life-size images of up to six people to be beamed to distant locations and recreated in a virtual space – in 3D and in real time. It has a big hint of Star Trek‘s holodeck about it.
Not only does this mash-up of telepresence and VR promise to make long-distance communication more immersive and fun; it is already being applied to an archaeology project that could help reveal the ancient secrets of European rock art.
To create a multi-user VR system, up to six people must wear bespoke 3D glasses and stand in front of a large screen, onto which 3D images are projected. Unlike a 3D movie, where everyone in the audience sees what is projected on the screen from the same angle, the Weimar team’s system takes into account your position relative to the display. Sensors on the glasses track each individual’s location, movement and even the tilt of their head.
In a demo of the system, six participants inspect a full-size projection of Michelangelo’s David. Each only sees the perspective that is appropriate to their location, so if they move from left to right, their view of David‘s profile changes, as if they were walking around the real statue. They can also see each other and interact with the display together, by pointing to it or by manipulating the virtual objects and environment using a tabletop trackpad.
“The key thing is that because it’s 3D, if one person points at an object, the others have to have their own unique 3D view to get what he’s pointing at,” says Anthony Steed of University College London. “Without this, the effect can be confusing or nauseating.”
To introduce telepresence, the team networked two displays, with each screen incorporating a Kinect depth camera, which films its viewers. Their 3D avatars are beamed to the other screen, where they are incorporated into the same virtual landscape. By combining the two systems, two remote groups of people can talk, gesture, even reach out to each other inside this environment (see video above).
“With telepresence, the arm of the person you’re talking to can come out of the screen and point at you,” says team leader Bernd Fröhlich. Product design would be one use for it. “Many car designers are in California but the car firms are in, say, Germany. With this system, they can walk round the car and point to different features, even reach into it.”
The system was presented at the IEEE Virtual Reality meeting in Orlando, Florida, on 19 March.
An even more fascinating application should be up and running in the next couple of years. Fröhlich is part of an archaeology project called Pitoti. It is documenting in unprecedented detail tens of thousands of figurines (the original “pitoti”) that were pecked into rock faces in the valley of Val Camonica, in northern Italy, between 10,000 and 2000 years ago. “It’s the greatest density of rock art anywhere in Europe,” says Frederick Baker at the St Pölten University of Applied Sciences in Austria.
In the next few years, the entire valley and its art will be captured in 3D, using satellites, scanners and cameras mounted on gliders and drones, as well as high-resolution 3D scanners at ground level.
The data will be fed into the Weimar VR system. Fröhlich envisages an immersive screen allowing users to fly into the valley and zoom in to see the pitoti’s fine structure.
New, portable high-resolution 3D scanners being developed by Axel Pinz at the Graz University of Technology in Austria will capture the pitoti down to a resolution of one-tenth of a millimetre. They will also capture the reflective properties of the rock so that its appearance at different times of day and year can be recreated. In the virtual Val Camonica, says Fröhlich, “at any time, we will be able to grab the sun and move it around to see different shadings on the pitoti”.
This last point is key for Baker, who claims the site represents the earliest form of 3D proto-cinema. Pitoti artists used chisels to make tiny peck marks on the rock, thousands of which were lined up for the final effect. In the full light of day, the shallow engravings are barely visible, but in the early morning and evening, when the light skims across the tops of the Alps, shadows suddenly make the peck marks pop out.
Baker thinks that as the light moves it may illuminate successive narrative scenes, which only come to life at specific points in the solar cycle. Fröhlich’s immersive recreation, Baker says, will be the “bridge into the past” he needs to test his theories.
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