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Wearable PC with an Artificial-Reality Helmet
Roland Piquepaille writes "In this short article, InformationWeek writes that 'two sexy technologies that flamed out five years ago -- wearable computers and artificial reality -- are combined in a new training-development system' for the military. This system, developed by Quantum3D, includes a binocular head-mounted OLED display and head-leg-weapon motion-tracking systems, integrated with a vest-worn tactical visual computer. It runs under Windows XP and is compatible with the 802.11 a/b/g wireless networking standards. It will be used by the infantry to train soldiers, but it looks so complex that I would need intensive training just for using it. Read more for other details and an illustration of the full scary system."
-1, Roland
Having XP in the background gives you something to blame for all the 'friendly fire'. Hey, I'd believe it!
Back in the early 1990s I started a company designing consumer VR ware for video games. We did lots of design work, got a few patents (hardware) on our work, then got a big contract from Sega to design key portions of their Virtua VR system - which was an HMD (head-mounted display, the real name for these things) that would plug into the Sega Genesis system to give you full immersion into the game playing world. We worked out all of the technical details, got the prices on the parts down to where it could sell for about $199 retail, and sat back and waited, and waited, and waited. Then Sega killed the project. We never heard from Sega why they killed the project. But, a year later, I heard a lecture from some researchers at SRI, who had done the testing for this helmet on Sega's behalf. Sega wouldn't allow them to release the results, so they did the tests again - on their own dime - and released them. And here's why you won't be wearing an HMD anytime soon:
1) Binocular dysphoria: when you wear a stereo HMD, your eyes/brain are getting one clue for depth perception (parallax) whereas in reality, there are six different cues for depth perception (focus plane, shadowing, etc) which your eye/brain uses to sort out what's going on in the z-plane of reality. While you're in the HMD, the brain adapts to this. Trouble is, when you take the HMD off, your brain is _still_ adapted to this. Now your brain eventually goes back to normal, but this takes some time, and it varies from individual to individual along a bell-curve distribution. Some people come back almost immediately. Others come back very slowly. That is an enormous problem if you go out and get into a car right away, or - as would be the case with the kids using the Virtua VR - getting onto a bike, walking down stairs, etc.
2) Torque: The Virtua VR was, like most early VR HMDs, closer to Darth Vader's helmet than to a pair of eyeglasses. That puts pressure onto the neck, and the neck can't really handle more weight than the head's already putting on it. Adding weight adds a lot of torque to the neck's movements, resulting in much more frequent neck strain.
3) Barfogenics: Although computers are more than fast enough to update images at 30 fps (even the Genesis could do this), the sensors which are used to calculate the yaw/pitch/roll of the head - in order to keep the image aligned with your proprioceptive sense of where your head is - generally don't work nearly as quickly. Most cheaper tracking systems, the kinds you'd find in consumer electronics, have some hysteresis associated with them. And that's bad, because if the image lags the movement by more than 50 msec, almost everyone will end up getting motion sickness. (Technically, this is known as "simulator sickness".) But the sensitivity of people to simulator sickness is also distributed on a bell-curve. Some folks get it very quickly, others don't get it at all.
So there you have it: Sega was told that they'd be selling a device that would cause kids to ruin their depth perception, would give them neck sprains, and would make them puke. Sega didn't even want to think about those kinds of lawsuits...
Today HMDs are lighter, but these fundamental issues remain, and remain unresolved. Yes, you can use optical tracking these days, because comupters are much faster with optical processing, but it's difficult to set up. HMDs are lighter, but they're still bad for your eye/brain. And until those problems get resolved, don't expect to be putting your head into an HMD.