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Not from a magnetic field from any reasonable distance, not by itself, liars.

You need a whole slew of additional sensors to even get close to such accuracies.

The Polhemous Liberty and other devices have been around for a while now and offer 0.03" accuracy with 6DOF: http://www.polhemus.com/?page=Motion_Liberty

These only use a single sensor (for a single location, can use many with one base station for multiple points tracking), I've used them for motion tracking and they seem pretty accurate to me. I'm not sure what you consider reasonable range, but considering the Razer system is supposed to be used with a PC, I'm guess you're not counting in the 10s of metres. This system has an optional source which can get you 5 metres of accuracy from the base station.

These are quite expensive (in the thousands of pounds sterling) so would be interesting to see how Razer managed it on the cheap.

Yes, you can do 6 DOF, with only magnetic fields, with sub-mm precision. Ascension and Polhemus are two companies that sell such products.

Look at the stats for Polhemus' Patriot. About 0.01 mm resolution at 1 foot. That beats your "liars" stat by about two orders of magnitude.

http://www.polhemus.com/?page=Motion_Patriot

This isn't new; it's just cheaper. Magnetic motion tracking devices have been around for two decades. I had a chance to try "virtual ping pong", like this thing does, on an Autodesk system demoed at the Hacker's Conference two decades ago. All the gloves-and-goggles systems use magnetic trackers like this. So do some of the tracking systems used for motion capture. If you've been to SIGGRAPH, you've probably seen a dancer up on a platform wired up with multiple sensors, driving an animated character on a screen.

The early systems suffered from serious lag, noise, and accuracy problems. The sensing was noisy enough that it had to be low-pass filtered, which introduced lag. You moved, then waited for the display to catch up. This was a killer problem with head-mounted VR. Accuracy was a problem. Even relative accuracy wasn't that good. When I saw these things at SIGGRAPH, I'd sometimes gesture to the dancer demoing the thing to put her hands together, forefinger to forefinger. If the character on screen showed the forefingers touching, the system had decent relative accuracy. Usually it didn't.

It's hard to tell from the video how accurate this new version is. With single-sensor demos, you can't see if there's serious error. But it's cheap. The Polhemus systems cost thousands of dollars.

I'd have to agry with you, it does seem "gimmicky". I am curious about studies in human computer interaction a 3d interfaces. 3d allows for more realistic interface metaphors, but can significantly complicate an interface, plus we don't have any 3d hardware. A mouse moves in 2 dimimensions (x and y coordinates only, no z or orientation information). Something like the polehemus fastrak would give six degrees of freedom and would allow you to interact with a 3d environment. I first saw the fastrak in a paper about a virtual bodhran. The paper on the "vodhran" is avail here.

Ok, I'm not as religous a microsoft hater as many here, but is there ANY good reason to have this run on XP?

You'll find a lot of exotic computer gadgets you find on the net tend to use Windows. I presume it's simply because it's probably cheaper to develop for just one platform, and they choose to use the most common one. Here are some examples of fancy displays and input devices I've found on the net...

• Autostereo displays
• Panoram Technologies
• Elumens Corporation
• Actuality Systems (site seems like it's down at the moment)
• Sensable Technologies
• Polhemus.com
• Ascension Technologies

Some of their products may be compatible with other operating systems, but most I looked at have a Windows bias.

Yeah, I've seen those. The FastSCAN actually has one of those pen things, if you look closely at the picture. There were more details on its use on the web page before, but they revised their website fairly recently. I also recall one that looked like a pen attached to a robot arm, but I didn't include it because I didn't have a link.

instead the(y) are digitized using one of many scanning techniques

What are the different scanning methods you are aware of? I've come across a few and I'm interested in knowing about others. I came across a method used by the National Research Council of Canada, and I think it has spun off into a commercial entity called Arius 3D. It captures surface 3D and colour data of objects on some kind of turntable, scanned by an RGB laser device. There's also the FastScan input device that uses motion-capture technology in combination with a monochrome surface laser scanner, so you move the scanner around, not the object. It was used for Lord of the Rings. I also came across the iModeller software package that apparently lets you use a standard digital camera to capture 3D images somehow. And I also recall seeing a documentary on television before where a RGB laser scanner, like the Canadian one mentioned earlier, was used to scan in ancient cave wall paintings. It scanned the 3D contours as well as the colour information of the cave wall surface, except the scanner laser moved around like a CRT scan line, so neither the scanned object nor the scanner needed to be moved. I couldn't find any information about that one on the web. I'd like to know of other methods and information about them on the web. Oh, and if anybody knows about that cave wall painting scanner device, I'd like to know more about that as well.

instead the(y) are digitized using one of many scanning techniques

What are the different scanning methods you are aware of? I've come across a few and I'm interested in knowing about others. I came across a method used by the National Research Council of Canada, and I think it has spun off into a commercial entity called Arius 3D. It captures surface 3D and colour data of objects on some kind of turntable, scanned by an RGB laser device. There's also the FastScan input device that uses motion-capture technology in combination with a monochrome surface laser scanner, so you move the scanner around, not the object. It was used for Lord of the Rings. I also came across the iModeller software package that apparently lets you use a standard digital camera to capture 3D images somehow. And I also recall seeing a documentary on television before where a RGB laser scanner, like the Canadian one mentioned earlier, was used to scan in ancient cave wall paintings. It scanned the 3D contours as well as the colour information of the cave wall surface, except the scanner laser moved around like a CRT scan line, so neither the scanned object nor the scanner needed to be moved. I couldn't find any information about that one on the web. I'd like to know of other methods and information about them on the web. Oh, and if anybody knows about that cave wall painting scanner device, I'd like to know more about that as well.

• 3D haptic input device
• 3D scanner
• 3D printer

Polhemus makes a handheld scanner:

Polhemus scanners

I believe there might be a couple of other projects making them but I can't think of any. You might find more here:

Simple3D

If you can render the entire image in the 1/700th of a second before the screen refresh, you can much more accurately track events than if it took you 1/60th of a second to render the image. USB mice allow a much higher sampling rate that you could take advantage of, for instance. When you incorporate things like motion-tracking polhemus devices, and a head-mounted display, things get really interesting.

CAVERNUS
- Check out applications to download. My personal favorite is Crayoland. :) There are also some early papers about the CAVE somewhere there

CAVE QUAKE II
- Quake II in the CAVE? What's cooler then that? It's quite unnerving fighting a Tank that's literally taller then you.

Teleimmersion at EVL
- Connecting CAVEs

Welcome to CAVERNsoft
- How to connect CAVEs

Center for Parallel Computers - VR-Cube
- The 6-walled CAVE in sweden. My office-mate saw this, said it was the most immersive experience he's ever done. Forgot where he was!

Ascension Techology Corporation
- These guys make the magnetic tracker we're using.

Welcome to Polhemus!
- another type of tracker

Pyramid Systems
- they'll build a CAVE for ya

AMPRO Corporation
- We use their projectors

CAVE Programming
- Some information on programming for the CAVE

CAVEdev::main
- Some other cool projects for the CAVE

enjoy!

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