Collaborative Visualization Environments

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Collaborative Visualization Environments

• Edward J. Wegman
• Center for Computational Statistics
• George Mason University

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Collaborative Visualization Environments

• Immersive Environments
• CAVE and PlatoCAVE
• Design Issues
• MiniCAVE
• Further Design Considerations

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Immersive Environments
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Immersive Environments

• Immersive
• Multisensory
• Vision 3-D Stereo
• Sound
• Sometimes tactile
• Visually Large
• Not a computer screen
• Not VRML

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Immersive Environments

• We have tended to see VR in three generic
  categories
• Individual Immersive Environments
• Group Immersive Environments
• Augmented Reality

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Immersive Methods
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Immersive Methods
Our system originally consisted of Virtual
Research Head Mounted Displays (HMD), Flock of
Birds Tracking Unit, and a SGI Crimson VGXT. This
was eventually replaced with a Onyx RE2 and later
with a SGI Onyx II with infinite reality engine.
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Immersive Methods
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Immersive Methods

• Problems with HMD
• Low resolution
• High tracking latency
• No group interaction
• PlatoCave
• Motivated by Platos Republic
• Motivated by Star Trek Holodeck
• Motivated by from ONR, ARO, NSF

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Immersive Methods
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Immersive Methods
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Immersive Methods
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Immersive Methods
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Immersive Methods
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PlatoCAVE

• PlatoCAVE Construction
• Room 20 ft each side
• 1 Projection Wall - 15 ft Diagonal
• SGI Onyx II with Infinite Reality Graphics
• Stereographics Projector
• 120 Frames per second
• CrystalEyes Shutter Glasses

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PlatoCAVE
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PlatoCAVE
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PlatoCAVE
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PlatoCAVE
The PlatoCAVE is an example of an augmented
reality environment. We say augmented reality
because the shutter glasses are transparent when
being used. So not only is the wearer able to see
the computer generated images in stereoscopic
3-D, but also the real environment including
others in the PlatoCAVE and also his or her own
body. This is generally not possible with HMDs.
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CAVE

• CAVE Construction
• Carolina Cruz-Neira
• 12 Foot Cube
• 3 Walls Floor
• SGI VGX
• 4 CRT Projectors
• CrystalEyes Shutter Glasses
• Head TRacking

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CAVE
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Design Considerations
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Design Considerations
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Design Considerations
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Design Consideration
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Design Considerations
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Design Considerations
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Design Considerations

• Angular Parallax
• Large parallax impedes stereo fusion
• Synchronization of Focus and Parallax
• Placement Behind Screen Improves Both Issues

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Design Considerations

• Head Tracking
• 6 degrees of freedom for HMD
• 3 degrees of freedom for Projection Systems
• Optimal for one viewer only
• Distortion and Latency
• Not good for group interaction
• Compromise
• Select one nominal viewpoint

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Design Considerations
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Design Considerations
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MiniCAVE

• Replace SGI with PC running NT and AGP graphics
  card with ?-channel
• Replace CRT projector with stereo pairs LCD
  Projector
• Add voice recognition

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MiniCAVE
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MiniCAVE
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MiniCAVE
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MiniCAVE
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MiniCAVE
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MiniCAVE
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Acknowledgements

• Funding ARO, ONR, NSF
• Principal Collaborators Qiang Luo, Jürgen
  Symanzik
• Other Collaborators Patrick Vanderluis, Xiaodong
  Fu, Ying Zhu, Rida Moustafa, Nkem-Amin Khumbah,
  Fernando Camelli, Antoinette Dzubay, Robert Wall

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Present Status

• MiniCAVE is awaiting permanent installation.
• U.S. Patent has been issued for MiniCAVE
  environment.
• Implemented for lt20,000.

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Inside a Metal Matrix
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Inside a Human Head
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Fractal Virtual Landscapes
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Flying through a Virtual World
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References
Wegman, E. J., Poston, W. L. and Solka, J. L.
(1996) Immersive methods for mine warfare,
MASEVR 95 Proceedings of the Second
International Conference on the Military
Applications of Synthetic Environments and
Virtual Reality, 203-218 Wegman, E. J., Luo, Q.,
Chen, J. X. (1998) Immersive methods for
exploratory analysis, Computing Science and
Statistics, 29(1), 206-214 Wegman, E. J., J.
Symanzik, J.P. Vandersluis, Q. Luo, F. Camelli,
A. Dzubay, X. Fu, N-A. Khumbah, R. Moustafa, R.
Wall and Y. Zhu, (1999) The MiniCAVE - A
voice-controlled IPT environment, Proceedings of
the Third International Immersive Projection
Technology Workshop, (H.-J. Bullinger and O.
Riedel, eds.), Springer-Verlag, Berlin, 179-190
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References
Wegman, E. J. (2000) Affordable environments for
3D collaborative data visualization, Computation
in Science and Engineering, 2(6), 68-72,
74 Wegman, E. J. and Symanzik, J. (2001) Data
visualization and exploration via virtual
reality An overview, Bulletin of the
International Statistical Institute, LIX(2),
76-79 Wegman, E. J. and Symanzik, J. (2002),
Immersive projection technology for visual data
mining, Journal of Computational and Graphical
Statistics, 11(1)