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University of Illinois uses a Cluster for Immersive VR
It seems the folks down at the University of Illinois at Urbana-Champaign have created a 6-sided CAVE like system called ALICE. But, instead of running it off of a SGI Onyx, they've developed a distributed environment for visualization called Syzygy. Slap a few computers together and make your own holodeck!
Is this, like, transcendentalist VR? Far out!
Or maybe it has something to do with emery; but how a powder generally used for grinding and polishing fits into VR, I don't know.
Now I'm going to read the article.
Karma: T-rexcellent.
This should make for some stupendous pr0n! Come on all you vouyers, start stringing those polygons together.
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This is one step in the right direction. Big things like these show you what commodity products of the future will be like.
You can't legislate goodness. Let each to his own destiny, by will of his freely made choices.
See their HOWTO for building up your own setup at
a me terExamples.txt
7 18 945
http://www.isl.uiuc.edu/ClusteredVR/szg/doc/Par
That seems like pretty doable by any geeks with enough boxes.
That would say if the 3D immersion has any usability to it at all, it will be in common use in 10 yrs. It might become the next big thing in living rooms like TV became 40 years ago.
However, what makes a new technology break through is not what it enables, but what you get with it. TV would have had no use whatsoever without the television programs made to be watched with it. Computers only broke through when there were programs for it.
Umm, I sense a great opportunity for all people who can really do great 3D graphics.
Not to mention what I already said about getting 3D GUIs off the ground at
http://slashdot.org/comments.pl?sid=25035&cid=2
Consistency is overrated.
...why is it called ALICE? Is it a deliberate attempt to confuse people who already relate ALICE to the ALICEbot? Is ALICE simply just a very adpatable acronym? Does ALICE the acronym deserve an acronym to describe it's acronymity? Adaptable Language In Crappy English, perhaps?
the moniker of "slap a few computers together and make your own" is a bit off. there are a ton of details and specalized software needed to make one. Granted, I think it would be really cool for a community college or a high school to make (where does one come up with 6 lcd projectors for dirt?)
cince it's slashdotted, anyone know of any projects like that that actiually release all the software used to make it work?
Do not look at laser with remaining good eye.
Most importantly, it is a display of what can be achieved with off-the-shelf PC level hardware. Even the projector system is a lot cheaper than that used by the CAVE systems. And it uses Linux too!
No entry found for Emersive in the dictionary.
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It's easy to play the devil's advocate, but I think there's more poewr for enthusiasm than downplaying here.
/. readers are grad students and builders, I leave as an exercise for the reader to wonder.
/.'s comprehensive archives on all the stories of this subject). Say it will hit market 5 yrs from now; you'd still have 5 years to make a product out of this to get it to market by my wildly suggested deadline of ten yrs from now.
The harder half is 6 or 12 videoprojectors (or more!), the mirrors and the (back) projection surfaces for the CAVE. Add in the tracking hardware (cost and complexity (ie EM interference))
Their source is GPL'd; it could be modified to use standard or flat monitors in a downsized setting.
you'll still need a team of grad students, builders and time.
Same goes for developing operating systems.
How many
you need a *big* room for one of these
Unless you downsize it. How many of us have spare space for wondrous technical projects...
The electronic (wall)paper is being developed at least by IBM and, err, was it HP (my memory fails me here and I'm too lazy to check
All that is needed for this breakthrough is all that work to create the usable content, just like DVD's need movies to sell.
I am sure some of us are willing to put together the effort in small groups of friends interested in this achievement. Just for the fun of it!
Consistency is overrated.
UMich has one too. It's very cool, but the computers to support it are kept on raised flooring with monks that tend them. The cool thing about this project is that it uses commodity hardware as much as possible.
(Hey Andrew, remember that conversation we had about synchronizing the output of several 3d cards? Looks like they did it!)
Wouldn't it be cool if someone built an 'arena' which matched a level from quake. People would ware a standard VR helmet, and a portable PC, and 'run' around the real areana, and be able to touch the walls, but only see whats presented them through the VR headset. There would be some sort of radio triangulation, which would track everyones position within the room, and relay the information back to a main server....- This would put Qzar/Laser quest to shame!
T.
ITYM "Immersive". If "Emersive was a word, It would probably mean something to the effect of "coming out of".
They have a similar system at Georgia Tech, called the NAVE. It's a three sided, small scale cave. The interesting thing about it is that they did it on the cheap. Just a bunch of students with hammers and nails to put it together. I think they said it cost 60 grand total in parts.
The PC's driving the walls were running Windows. So when we got a demo, they rebooted the machines first off. They said to clear out all the OS cruft. The synchronization between the walls was not very good at times. I'd say large fractions of a second. Thats the one thing a big SGI gets you, really tight synchronization between the walls.
dave chen
Noting that this is clustering software for a *CAVE*.
1. You can't use "standard or flat monitors" in any form of "downsized setting", because unless you are 6 inches high, it's not going to be immersive. You can't stand in the cubic space formed by the faces of 6 monitors, flat or not, unless you are a person of very very small stature. Even if you can find a 6" high person to get in this contraption, they'll probably get fried by all the EM radition & heat after a few minutes, so you'll need a supply of these people...
2. Bringing up kernel.org looks like blatent karma-whoring - it's completely irrelevant. The problems you missed, and which I pointed out to you in my first post are the physical problems - you have to build an immersive space environment - a physical one - out of wood. You can't email an 12 foot high wooden structure around on the internet you know!
3. (You need a big room for this) "Unless you downsize it". Oh sure, if you can also "downsize" your users. You have to build something that you can get inside of. There's a limit to downsizing - at the limit is your body!
If you're only going to use a powerwall or something it's a different kettle of fish, and you can just hook up WireGL or something of that nature with what I expect will be a lot less effort.
So as I attempted to point out (and obviously failed) in my first post - there are real physical engineering problems that make the construction of your own CAVE environment much much harder than downloading some code and playing with the configuration files.
0.02
Tales from behind the Lagom Curtain
ISU has probably the premier researcher in this area, Dr. Carolina Cruz-Neira. Here's some info on the environments at ISU: C6 and more...
Shut up, be happy. The conveniences you demanded are now mandatory. -- Jello Biafra
Post Tramatic Stress Disorder treatment - The cheaper it is the more that can be helped sooner.
The article sort of makes it sound like this is groundbreaking work for UIUC.
UIUIC, if I'm not mistaken, is the location (or one of the locations) of the National Center for Supercompuing Applications (NCSA anyone?). They already HAVE a passel of really funky VR & immersive environments.. CAVE, versadesk, that funky classroom....
So they did a 6 sided cave instead of the old one (3 or 4? I forget if the floor was done or not). I mean, it's great news.. and using linux is cool.. but really... It's interesting, not groundbreaking.
As for those saying 'But they will need good synchronization and trackers'. It's NCSA. They have lots of this gear already.. they already have a cave, remember.
Dammit. I was only a few minutes away from there on my travels once.... I wish I could have gone for a tour.
He originally wanted to name his company "Syzygy"...
You see? You see? Your stupid minds! Stupid! Stupid!
To recreate stereo vision, it actually is more appropriate to utilize non-Euclidean geometry. In this specific case, an infinite number of parallel lines go thru a single point. Does anybody know if this system uses such? It would require a fairly massive refit to standard graphics programs.
So long and thanks for all the fish . . . !!!
However, LCD projectors can not do active stereo. The projector displays the left eye view and the right eye view sequentially, and the active glasses (which must be somehow synchronized to the projector) block the right and left eyes sequentially. So at any given time, one eye is viwing an image, and the other sees pure black. If the refresh rate is too low, then the stereo starts to become flickery. And uncomfortable to the eyes. You can view stereo with a 60Hz display, but for most people, five minutes is about all they can stand. At 96Hz, one can view stereo comfortably for quite a while. 120 hz is even nicer.
From what I understand, LCD panels can't achieve these speeds (something to do with the energy requirements, and especially the cooling requirements, going up exponentially with Hz) One can use CRT projectors, or DLP projectors (I saw such a CAVE at EVL in Chicago, birthplace of the original CAVE)
With passive stereo, LCD's can be used - basically you just shine 2 projectors fitted with polarized filters at each screen, spend about a week aligning everything, and you're ready to go (special lenses may be needed so that alignment can actually succeed)
Now, there actually are some other options - the least interesting one is anaglyphic stereo (red/blue glasses). We'll let that one slide.
However, many new auto-stereoscopic technologies (glasses-less) are being developed.
There is lenticular - based on the same principle as those doodads you used to get in cereal boxes, where the picture would change when you rotated the thing. Now those things only had 2 images, and you had to rotate it 30 degrees to change the image. But you can make 'em so fine that each eye sees a different image. Put a display behind it, and you have autostereo. see here
One of the funkiest methods I've heard of being tried is to use pupil tracking. To understand this, you need to know that the eye is a very low resolution 'camera' for the most part. However, in the dead center of the retina, there is an extremely dense set of receptors called the fovea. It covers only about 1-2 degrees of arc, and this is where your eye picks up pretty much all of the detail.
Now, if you use pupil tracking (which can be done without the viewer having to wear any special equipment), then you can determine the region of the screen each eye's fovea is covering, and draw the corresponding image there. I haven't found an online reference to this yet, but I think it's a cool, if not a little difficult, solution to autostereo.
-matt
Really, it doesn't have to take up *that* much space. I've worked in the CAVE before, and while it's somewhat large, there's no reason it couldn't be made smaller these days, given that three-gun CRT projectors are outmoded, and with a single gun projector you could use much smaller mirrors. Make the walls 6' high, and you'd need a room maybe 15' by 15', perhaps 20' by 20' to get the job done. And the ceiling needs to be maybe 8' tall, given some planning. (the CAVE system doesn't have a ceiling surface, but it has a floor - there's a projector pointed straight down via a mirror).
Granted, the 12 CPU Onyx2 (named Cassatt) takes up some room... but that is physically located in a different room in the Beckmann setup, and video is piped in.
So basically you need:
- 4 LCD projectors, at a minimum of $1200 or so each for cheesy ones.
- 3 rear projection surfaces - since we're using cheap projectors, you may as well use white bedsheets attached to a homebuilt wooden frame
- 3 or 4 small-ish mirrors, unless you've got room to put the projectors all around the area.
- (the biggie) Lots of CPU, and software.
Thankfully, the software mentioned in the article is freely available, so that takes some cost out of the problem. Now you just need a minimum of 4 graphics pipes, say $200/each GeForce2 or whatever's available, and machines to put them in. Perhaps with some nice fast interconnects - gigabit ethernet will do in a pinch, there isn't such a need for things like Myrinet anymore, although Myrinet is doing some truly wicked things these days (2+2 gigabit full-duplex networking!)But I digress. As you can see, it's doable.
CAVE, while a nice hack, is really a big waste of time, space, and money, when compared to the immersive advantages that RSD displays will bring to the mainstream in a few more years.
I don't mean to knock the guys who work on CAVE... it's awesome considering current limitations...
--
Power to the Peaceful
OK, so I go to UIUC and haven't heard of this. I'm only a freshman and not even in CS, so that seems probable. But get this - a road right next to my grandmother's house in good old, technologically backwards Inverness, Florida carries the exact same amazingly-lacking-in-common-vowels name on one of its roads. This is not even a normal road either. It's a road that goes for about five feet and then vanishes into a banal brown path. Now, I've got a fairly extensive vocabulary, but this word is utterly foreign to me. How could it possibly link the meager stretch of road in Inverness to an immersive virtual reality visualization system? Clearly a Google search was the first step in my investigation. I found that these are not the only products to carry this eclectic word as their name. We've got Syzygy.net, a european firm specializing in the creation of e-businesses, a page documenting religious cults, a hardcore eclectic videogame magazine, and, my first solid lead, a company selling astronomical simulators. The last seemed to be the only lead worth following, and a dictionary.com search ended my confusion. Apparently, Syzygy is the key point in an ecclipse when the sun, moon, and earth lie in a straight line. For what it's worth, you can also have multiple Syzygies, but that word is not nearly as fun what with its normal vowels. My quest is now complete. Alas, now I'm at a loss as to what I can do to forstall finding employ over winter break. Ideas are welcome.
Ok, you know about this system, and you know what goes into building a cave, right?:
1. Several boxen
2. This software
3. Several projectors
4. A tracking system
5. 3D shutter glasses
All of which can be expensive. If you aren't thinking. If you aren't hacking.
Ok, you have the boxes and the software - that part is easy, and relatively cheap. But hey, six boxes can be expensive, especially when you are dropping good video cards into each. So what to do?
Use three boxes instead. Each box should have a dual head card. Then build a three wall cave instead. Such a configuration can be done either as a front view and two sides, or "staring at a corner", that is, using two adjacent sides and the ceiling for the projection surfaces. The other two sides can be rigged with black velvet curtains to block light.
Now, you need projectors. As we all know, such projectors aren't cheap - but they are coming down in price. If you can pick up six projectors (for stereo - two per wall) cheaply, more power to you. However, most of us won't be that lucky. So, what to do?
Build your own projectors!
This site was spun off, crazy as it sounds, from the 100 Inch TV list on the same server. The group is focusing on building video projectors using cheap and easy to get LCD TVs, etc. Robin Holland also wrote a VR Book that detailed such a projector (see my VR site for more details on that book) back in 1996 (as well as the 100 inch TV projector, but that was done by others before him and all this long ago, called the Warper for the AcidWarp program).
Such projectors should prove not too difficult to build, and cheaply - but won't be high-res or anything - but they will be usable! I have a Fujix P-401 that is similar in design that is watchable, so I know what it would look like. If you build six of the projectors, you can use them with shutter glasses for stereo...
So, you need shutter glasses! Where to get 'em cheaply? Try Ebay! Look at this link for the systems currently on auction. There are a ton! But how to get 3D with your cheap LCD projectors (or even normal projectors)? Well, buy a pair of LCD 3D glasses for yourself, then a pair for every two projectors! Each pair will have two shutter LCD light valves - pull those out of the glasses, and place in front of each projector's output, and sync those with the glasses on the user. You may need to add fans to blow across these shutters to keep them from being overheated by the projector light source. Instant cheap 3D (but it may give you a headache after extended use)...!
So, now you need tracking. This is the really tough part - but it is possible to build this yourself. If you look at my site, you will notice that in Issue 2 of Cheap VR, I tell how to build a 3D magnetic tracker. Well, I have news for you: I have found someone who has done it, independently of my article (that is, he didn't know about my site or articles):
Juan's Homemade Magnetic Tracker
He has published a Circuit Cellar article on the tracker last August (2001) - detailing the construction and such. I was able to get a copy from him, and he says he plans on putting the article on his site for download. It looks like he is having traffic quota issues on part of the notes currently, but the PDF file will tell you a lot, and explains the math and theory behind it all (he covers a lot of things I didn't think of). Anyhow, notice in the pictures and movies that his hand is being moved inside a cube structure? That cube is the 3D tracker transmitter, similar in scope to what I wrote a long time ago. Anyhow - he has told me he is planning on building a 6 foot per side cube, to allow the tracker to track a user inside the cube. Check this: That cube structure can be your frame for the CAVE.
Build a cube of sufficient size (6 foot per side or larger), add the coils, then add the projection screens (Want a cheap back projection screen? Use white-plastic painter's dropdown "cloths", or use clear plastic "cloths", then frost them with glass frosting paint. Finally, stretch the plastic on the frames). Put the edges right against each other, so that the "seams" between the screens are minimized. Use the homebrew projectors to project against them (for the dual projection system, place the projectors as close as possible together - there will be some keystoning, but hopefully not too much to cause major issues).
There you have - a quick and easy CAVE system. Now, mind you, this won't be a simple construction project - not at all. Main reason is size, because you will need a room larger than the "inside" room you are building for the CAVE. But I can see this being done in a spare bedroom, or maybe a garage, given enough ingenuity.
So, now that you have an idea - someone try it out (hell, I would if I had the room) - and email me and let me know how it works...
Reason is the Path to God - Anon
Cheesy is right. I imagine for that money you get 800x600 resolution. A 1280x1024 projector is thousands more. But anyway...
You want something that won't flap in the breeze. To get any decent focusing you need F-L-A-T.
Skip the floor projection, I guess - it would require a hard screen - think mid-five-figure range for quality, I dunno how cheap you could go. The sides could perhaps use latex, for which the big boys would still want at least four figures per each ... guess it would depend on size. I'm not sure offhand what you could build on the cheap, but I strongly suspect that bed sheets wouldn't cut it.
...and mounts which let you adjust at least one angle - you don't want to hard-code this or your final adjustments will Not Be Fun. Also, I don't know if this is critical for a "budget CAVE", but for our VR center here we have front-silvered mirrors - for obvious-I-hope reasons.
Yeah. And not just CPU but lots of motherboard bandwidth - you'll probably want 66MHz and/or 64-bit PCI for the GigE, and the same (or AGP4x) for graphics.
"How can you claim that you are anti-crack, while still writing a window manager?" — Metacity README
I am fighting and losing a battle with my "last word" neurons :-)
As you can see, it's doable.
"CAVE on the cheap" is clearly doable: it's already been done with the NAVE, and the "Wedge".
Really, it doesn't have to take up *that* much space.
The article mentioned a 6 sided CAVE. It's the floor/ceiling setup that require the extra vertical space. If you dont have them, of course you need less space.
0.02
Tales from behind the Lagom Curtain