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22 | NewScientist | 22 June 2013 TECHNOLOGY SPECIAL / Virtual reality ONE PER CENT GAUTIER STEPHANE/SAGAPHOTO.COM / ALAMY Going in, eyes open Firefighters in a burning building tend to be working blind. ProFiTex, a virtual reality project at the Vienna University of Technology, Austria, aims to help them visualise their environment. The system uses infrared sensors to overlay surface temperatures on a head-up display. It also shows a 3D model of the surroundings, created by a head- mounted depth camera. This will give firefighters an idea of whether it is safe to enter a room and how to navigate a dark building. All the data can be sent via a fibre-optic cable to the fire crew outside, to help make decisions. Wiggle your new tail Virtual worlds are great, but can we get used to virtual bodies? It turns out we can control an avatar in the form of an animal if our movements are mapped on to its digital representation. William Steptoe at University College London gave 32 volunteers an avatar with a tail. He found that, within minutes, the volunteers had learned to control the tail by moving their hips, using it to touch objects beyond the reach of the avatar’s arms. Virtual bodies could one day let us interact with computers in new ways, says Steptoe (IEEE Transactions on Visualization and Computer Graphics, doi.org/mvw). Optical illusions help you explore a virtual world on foot I’M WALKING through a villa in sunny Tuscany – or so it seems. Donning the Oculus Rift headset (see page 19), I am immersed in my environment. But it’s not just the wraparound visuals that are fooling me. Thanks to a few clever perceptual tricks, I feel like I’m walking naturally, even though my feet are only moving back and forth on a static platform. The buzz around the Oculus Rift headset is giving virtual reality a new lease of life. But however immersive the visuals, you are usually stationary when using it, moving your avatar via a control pad or keyboard. Now hardware is adding the sensation of movement to virtual adventures, without leaving you feeling nauseous. Unlike joysticks, devices such as the WizDish – which lets users glide in any direction – can integrate real motion with moving visuals. This makes it easier to exploit an illusion known as vection to make people feel as if they are moving faster than they actually are. “Some game characters run at an equivalent of 40 miles per hour, so it’s just as well you don’t have to emulate that,” says Julian Williams, WizDish’s creator. With the WizDish, a person experiences the sensation of walking simply by sliding their feet back and forth on a slippery disc. This provides feedback to the brain about where a person’s limbs are and how much they are exerting them, in the same way actual steps do. “A key feature is that your centre of mass remains equidistant between your feet, as it does when you walk for real,” Williams says. Another system in development is the Omni treadmill made by Virtuix, a Kickstarter project that has raised more than $810,000 in just two weeks, after asking for $150,000. Users climb into a harness on a circular treadmill that has a padded band around the waist. The treadmill’s floor is almost frictionless and moves as the user runs in any direction. Exploiting illusions can really enhance the feeling of immersion. Frank Steinicke from the University of Würzburg in Germany tricked users into thinking they were walking in a straight line by rotating the view seen on one side of their virtual reality glasses. Without realising, users compensated by walking a circular arc in the opposite direction. His team is also looking at how optical illusions can be exploited in virtual worlds to match real-world perceptions. By adding certain visual tricks to a moving scene, the wearer can be fooled into thinking they have walked further than they really have (Displays, doi.org/mt5). But apart from replicating the real world, illusions have the potential to create out-of-this-world experiences. Realism is useful, says Inger Ekman at the University of Tampere in Finland, but only to a point. “Then it needs to be bigger, at least for entertainment purposes. We’re after the wow factor, not realism.” Sandrine Ceurstemont n WIZDISH The WizDish tricks you into thinking you are walking “Exploiting illusions can really enhance the feeling of immersion in a virtual world”
