Click here to view the embedded video.

From VR-Tifacts, where you can find a lot more videos :

From 1991 to 1996 W Industries Virtuality systems defined the image of VR in the location based entertainment arena. (…) Virtuality, first using an Amiga platform and later a 486 PC, achieved a remarkable quality of game play for those early years. This collection of videos will give you a flavor. Thanks go out to Fronzel who generously compiled many of these. Watch!

VRPN (Virtual Reality Peripheral Network) is a free, open source, tool that handles many VR devices.

VRPN acts as a device server. You configure VRPN to use your devices, then your program can easily connect to the server to get the device data in a standardized way.

VRPN is used by a lot of VR applications: commercial ones like Virtools, WorldViz, but also free applications like OpenSceneGraph, or Panda3D.

VRPN is cross-platform and runs on many different OS inclunding Windows, Linux, MacOS …

We recommend the usage of VRPN if you want your application to be compatible with the VR Kits.

I’ve managed to have a pretty good calibration, and I’ll detail the steps here.

Some important issues remain, see at the end of the article, but the results are already very interesting !

Definitions

VR cameras compute a correct perspective when looking at a screen with your head tracked, resulting in an asymmetric frustum.

I was afraid that if I give an asymmetric frustum to the 3d Vision driver, it would go crazy, but it doesn’t !

It *seems* to compute the correct frustas for both eyes. I don’t have a formal proof that everything is correct yet, but I have several clues.

(With a Quadro you don’t have this problem since you compute the frustum for both eyes manually.)

The first clue is that the stereo “feels” good. This is not very scientific but it’s already a good start.

Then I had two problems :

- I didn’t know what the 3D Vision driver supposes the distance between my eyes is. It needs to be exactly the physical distance otherwise the objects will appear smaller or bigger than natural. Remember we’re trying to make a 1:1 mapping between the virtual and the physical world here.

- The driver also assumes a screen distance, that is the distance between your eyes and the screen. 3D objects that stand at the same distance are in the plane of the screen : the parallax (distance between the red and blue dots bellow)  is zero, the left and right pictures for this object are at the same place. But it doesn’t know the particular distance of my setup.

( Figures from this course )

The 3D Vision driver allows you to manipulate a “Depth Amount” (probably the Inter-eye distance) but this has no metric. You can also manipulate the convergence (i.e. the screen distance), but you still don’t have a real measurable value.

( There is also a “Cycle frustum adjustment” function but I have no idea what it does appart from stretching the frustum!)

Calibrating the convergence

Please note that this is a very empirical method, so if you see any flaw please let me know !

The easiest thing to check is the Convergence, ie the distance between my eyes and the screen. As we said, if an object is at the convergence distance, both left and right pictures for this object will be at the same place.

So in Virtools I created a 3D scene to test that :

The box has the same width and height as the screen, and the front of the box exactly fits my projected screen.

The first ball (lowest one), is exactly at the convergence distance, so if the convergence distance is set right in the 3D Vision drivers, there shouldn’t be any parallax.

See the big ball ? It has two images, which means that the convergence is not right ! The object is too far away, so by increasing the convergence, I will bring it closer until it has only one picture.

Now that’s better. For more precision, make sure that the center of the ball has zero parallax.

Calibrating the inter-eye distance

Now what about the inter-eye distance ?

(This is also very empirical, so if you see a flaw let me know!)

If you look again at the Figure 1 above, you’ll notice that if we place an object infinitely far away, its parallax should be exactly the distance between the eyes.

I wanted to try another method :

Suppose I place an object at the same distance from the screen than my eyes. By using Thales’s theorem : p / IED = d /2*d

So the parallax of this object gives me half the inter-eye distance.

By changing the “Depth amount” of the 3D Vision driver you change the inter-eye distance until the measured parallax is 6.5cm / 2 = 3.25 cm :

(notice my awful wallpaper and the big size of the pixels…)

I had to push the depth amount to nearly the maximum to get this separation.

Checking the calibration

One great way to check your calibration is simply to place a virtual object that has the same shape and the same position as a real object.

Since we’re trying to achieve a one to one mapping from the real world to the virtual world, the two objects should match perfectly.

Actually it’s exatly the way that car manufacturer are calibrating their cave, with a big physical cube. The depth perception for them is critical, so with this method they’re both checking the cave configuration and the inter-eye distance of a specific user.

I’ve tried to do that, and within a few centimeters (for a box of 33cm deep stuck to the wall), the real and the virtual box approximately match.

I’ve reached the Gametrak’s limits in terms of precision. Hopefully it will be more relevant with a better tracking.

But all in all, it seems the calibration is not so bad!

Issues

Unfortunately, some non negligeable issues remain :

- If you have followed closely, you’ll wonder what happen when you move your head closer or farther away. You’re right, we should modify the convergence distance of the 3D Vision drivers dynamically ! I have yet to see if that’s at all possible other than with the keyboard shortcut.

- Another problem is that the 3d Vision driver assumes that your eyes stay horizontal and parallel to the screen. You can’t bend and you can’t look from the sides, otherwise the stereo will be wrong. It may be possible to diminish this problem by reducing the inter-eye distance when we detect the user is bending or rotating.

Conclusion

The 3D Vision driver is meant to transform any 2D Game into stereoscopic 3D. It assumes that the player stays static in front of his screen, and that he adjusts the inter-eye distance based on his comfort and not to have a realistic stereo.

After some calibration it’s possible to get close to an interesting solution for a homebrew VR setup. If you don’t need precise depth and size estimation, it will probably be good enough for you.

But if you want perfect stereo and head tracking, the easiest way is still to use a Quadro, because it gives you a real quadbuffer where you can compute yourself the correct perspective for both eyes !

I have to say I’ve been waiting to have this kind of setup at home for 15 years, and I could finally build one myself !!

A 2.20m x 1m65 3d screen ! With that I can look at the 3D pictures and movies I took with my Fuji W1 3D camera, play (in 2D) with my game consoles, watch (2D) movies and .. get immersed !

Click here to view the embedded video.

As you can see it fits in a very small parisian room. The projector has a throw ratio of 0.68, which gives me the 2.20m width at a distance of only 1.5m. This also has the big advantage that, as this is front projection, it allows me to get somewhat close to the wall without casting a shadow.

The parts list :

- Viewsonic PJD 6381 projector : 800€

- NVidia 3D Vision kit : 150€

- Wiimote + Nunchuk : 50€

- A Gametrak : 20€

Total : ~1000€ !!!

Remember that every part is replacable by a more efficient one as long as you follow the VR Geeks specifications for the VR Kit – Wall!

I especially hope to get rid of the Gametrak wires soon And I also need to change my wallpaper, it has a too funky texture.

Now we need good applications and games to go with all that !! So join the VRGeeks and start creating your setup and applications!

David came home to test it and found it promising :

( oh and he also tested the HMD kit

By the way we’ve just started a new webpage : http://www.VRGeeks.org

There you can join the (worldwide) VR Geeks mailing list ! I’ll make another announcement later but you can already join early

The idea of the kits is that we don’t impose any hardware, you can use whatever hardware combination/tracking method you want ! Here I’m using the most cheap/usable ratio I’ve found. More infos on the VR Kits here. This is just a quick first version to get the idea, and you’re invited to join the discussion !

Here’s a quick video :

Click here to view the embedded video.

And here’s the parts list for this setup :

- Vuzix VR 920 HMD (350€)

- Spacepoint Fusion orientation tracker (100€) (my Vuzix tracker is completely unusable..)

- Wiimote + Nunchuck (50€)  for some buttons and a joystick.

- A Gametrak (20€) to get the head and hand position.

Total : ~500€ !!!

Everything fits nicely in my small backpack so I’m able to do some nice demos around. Granted the Gametrak tracking is a bit cheesy and you’re quite tethered for the moment, but it is *very* cheap and works really well. Everything is replacable by more interesting/expensive/clever solutions.

I would need a second Spacepoint Fusion to get a correct Wiimote orientation (yaw..), or maybe you will be able to help … More on that later

I also have a nice setup with a 3d projector.

(Update: David testing the kit)

Is it 3D computer graphics ?

Is it stereoscopic ?

Is it just because it’s not in 2D ?

Philippe Fuchs made me laugh last week when he said : “Hey I finally found a real 2D movie !!!”

Click here to view the embedded video.

So I guess what we all do is 3D, 3D, and 3D ! 3D because we can perceive depth, 3D because it’s computer graphics and 3D because it’s stereoscopic !

So, of course they have a Cave :

- Ford’s Cave (c) CrunchGear -

“This 3D environment is designed not so much for the ergonomics (…), but rather for style and craftsmanship. Four rear projectors generate 3D images on three sides and above the tester. The 3D glasses are equipped with motion-tracking sensors to further complete the environment.”

A powerwall :

- Ford’s PowerWall (c) CrunchGear -

“Imagine a large room with a single computer workstation and a 20-foot screen as its display. That basically Ford’s Powerwall. It’s a place where designers to executives to auto dealers can gather and get a high-res look at Ford’s current and future lineup.

It’s a simple concept with Sony 4k projector connected to just a single high-end workstation, but the results are spectacular. Designers are no longer tied down to their cubicles and can explore their work in larger-than-life dimensions using AutoDesk & AutoStudio CAD programs to creating spectacular animations in Maya.

The Powerwall rooms are also equipped for worldwide collaboration and any one of them can host virtual meetings with the other seven Ford Powerwall studios found across the globe.”

And a simulator, the Virttex :

- Ford’s VIRTTEX (c) CrunchGear -

“Ride testing is key to any vehicle’s development. It can be expensive constructing prototypes that do not function right or are simply wrong. This is where the VIRTETEX simulator comes in.

A 24-ft dome houses a full-size vehicle — in this case a Taurus X crossover — that’s connected to a series of computers. Hydraulics, five projectors, and a bunch screens then immerses drivers in a virtual world.

The benefits are nearly endless. No more expensive and potentially dangerous test vehicles as the system can simulate most of the driving dynamics of a compact car or full-size truck. Testing and polling can be done in a controlled environment without any variables. And it’s just so cool. Imagine playing Burnout Paradise or Grand Turismo in this thing. The Ford engineers said they’ve never broke out the games but you know the six blade servers with high-end Nvidia graphic cards that powers the displays are just screaming for a bit of downtime.”

But I think my favorite toy would be the Programmable Vehicle Model :

- Ford’s Programmable Vehicle Model (and Elizabeth Baron) (c) CrunchGear -

“Much of a vehicle’s testing is now done virtually [Cb: How much?], a processes that helps streamline development while keeping cost down. Ford utilizes numerous tools for virtual testing with the PVM at the heart of the process. It immerses the tester in a virtual world assisted by the physical presence of a configurable vehicle sled.

This testing sled is a complex platform that’s able to match the physical dimensions of nearly any vehicle. Once the physical properties are set, a tester sits in the sled wearing a head-mounted virtual reality display equipped with reflective spheres to enable 1-1 movement mapping. A pair of gloves with the same IR-visible balls helps complete the illusion.

The goal here is to allow designers and engineers the ability to test out their designs without building a full-scale working model. Nearly everything from seating position to steering wheel position to blind spots can be evaluated and worked out.”

Very advanced passive-haptics ! Moving the different physical parts so that it matches the virtual car is brilliant. And combined with an HMD you can completely occlude the physical skeleton and dress it with any car you want.

That’s a really practical and useful VR center, helping them to have better car faster, saving them months of developpment and saving them millions of dollars in development !

Thank you CrunchGear for the overview !

Featuring David “iVEvangelist” Nahon!

Randy Pausch once said about VR : “It has to be experienced first-hand. Simply talking about it is like describing color to a blind man.” Going to Laval Virtual is a good way to experience VR and open your eyes

Here are the ones related to immersive VR :

Click here to view the embedded video.

Click here to view the embedded video.

- VR4D by Clarte. Original video here -

Click here to view the embedded video.

- Multiplatform distant collaboration -

Click here to view the embedded video.

- Darwin Fear Theroy -

Click here to view the embedded video.

- AR Laster See-through glasses -

Click here to view the embedded video.

- Immersive Rail Shooter -

Click here to view the embedded video.

- Immersive Music Painter -

Click here to view the embedded video.

- Spider Hero -

Click here to view the embedded video.

- V3S. Not completly immersive VR but still has plausibility illusion -

]]> http://cb.nowan.net/blog/2010/06/09/laval-virtual-2010-videos/feed/ 3 http://cb.nowan.net/blog/2010/06/09/laval-virtual-2010-videos/?utm_source=rss&utm_medium=rss&utm_campaign=laval-virtual-2010-videos http://feedproxy.google.com/~r/vrgeek/~3/pc4Z5D7wQHY/ http://cb.nowan.net/blog/2010/06/01/quick-links-3/#comments Tue, 01 Jun 2010 17:30:49 +0000 cb http://cb.nowan.net/blog/?p=1001 Don’t have time to post a full article ? No problem, Twitter to the rescue !

(And if you’re in Paris next moday (7th June), feel free to drop by our VRGeeks bar evening !)

- IronMan simulator #diy #ivr http://bit.ly/d48acQ

- The sense of body ownership and 3D virtual reality: http://bit.ly/amkCBy

- Unity3D in Chrome without any plugin installation! http://bit.ly/cSxhHr

- Natal To Cost $149 and to be released 26 oct – Source http://shar.es/mjVnM

- Even “Looney Tunes” Gets Into 3D Craze http://bit.ly/c6iFoF #s3d#stereoscopic #cartoons (via @3DMOVIEMAN)

- Samsung shows a 19″ trasparent OLED screen! http://bit.ly/cKwSXt(via @regarde)

- Impressive and cheap “real-time hand-tracking with a color glove” #ivr http://bit.ly/an87uR

- Body ownership can be transferred to an entirely virtual body (via slapping ?!): http://bit.ly/aP53uJ

- RT @TopsyRT: AppleInsider | Apple exploring interactive, glasses-free 3D holographic displays http://bit.ly/dgqzNT

- RT @DepthQs3D: Sharp 3D camera module for mobile devices http://bit.ly/cBPJeu – This is the kind of tech that will grow s3D

- RT@DepthQs3D: Dimension 3 Expo, Paris June 1-3 — “Top Thirteen S-3D Questions Answered by Stephan Faudeux” @Nick_Dager http://bit.ly/dhq5f9 #s3D

I’ve already tried briefly in another article to define what is not VR but I didn’t have a very precise definition of what I believe VR is. Everyone in the field has his own definition, and I think I’ve finally found what is the distinctive factor for me (hint, perceptive immersion). Of course now that I’ve realized it I find that I agree with the definition a lot of people.

Anyway for me VR is Immersive Virtual Reality. You can find my definition along with extensive explanations on this page.

There has been a great  debate on the 3DUI mailing list about the definition of VR and thus what should the IEEE VR conference be about.
This debate fueled the panel discussing this topic at the IEEE VR 2010 conference, hosted by Jeffrey Jacobson and Chadwick A. Wingrave and prestigious panelists such as Doug A. Bowman, Frederick P. Brooks, Jr., Robert Jacob, Eric Klopfer, Joseph J. LaViola, Jr., Albert (Skip) Rizzo, joined later by Mel Slater. This panel and most of all Mel Slater’s work inspire my position. You can read the slides of this panel here.

I’m happy to report that Fred Brooks is as extremist as me as he said the IEEE VR conference should only be about Immersive VR and nothing else. This would probably shorten the conference a bit, and most certainly avoid keynotes about SecondLife. No more AR, no more multitouch.

Don’t get me wrong, I think SecondLife, AR, multitouch are really important and passionate subjects. It’s just not iVR ! Sometimes some AR or multitouch techniques are used for iVR but that’s not the norm.

So my short definition, for the moment, is :

Immersive Virtual Reality (iVR) is a set of technology and science required for a user to feel present, via perceptive, cognitive and functionnal immersion and interaction, in a generated environment.

Again for a longer and more detailed explanation,  check this page, which will probably evolve in time with my understanding.