Virtual Reality CAVE |
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The CAVE® (Cave Automatic Virtual Environment) is currently the most advanced system for immersive virtual reality. It provides its users with the convincing illusion of being fully immersed in a three-dimensional world that is computer-generated. This world is presented in stereo as well as at life-size scale. As a superb tool for the visualization of complex environments, the CAVE facilitates the exploration, understanding, and evaluation of any real or abstract environment. The immersive experience includes unrestricted navigation (look-around, walk-around, fly-around), interaction with virtual objects, and enhancement through directional sound. The 3D Lab offers a wide range of services surrounding the usage of the CAVE. This includes software support for the development of CAVE applications, introductory seminars and workshops, training for CAVE users, demonstration examples, and individual consulting. |
The CAVE concept was developed at the University of Illinois at Chicago and provides the illusion of immersion by projecting stereo images on the walls and the floor of a room-sized cube. Our CAVE uses three walls and the floor as projection screens. The projectors are located outside the CAVE. The users entering the CAVE wear lightweight LCD shutter glasses for stereoscopic viewing. The resulting effect is so compelling that, after a short while, the walls and corners of the CAVE are mentally blocked out by the human brain. The floor projection allows three-dimensional objects to appear inside the CAVE room, thereby, confronting the user in a convincing way. To create the stereo effect, the images for the left and the right eye are projected in a rapid, alternating sequence. The LCD shutter glasses alternately block the right and the left eye in synchronization with the projection sequence. |
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The perspective images are generated for the current position of the so-called "leading" viewer. An optical motion tracking system traces reflectors attached to the glasses of this user and continuously measures position and orientation of his or her head. These measurements are processed by rendering algorithms that calculate and adjust the projected images in real-time as the leading viewer moves about. For the additional (passive) viewers, the virtual environment may appear slightly distorted depending on their position in the CAVE relative to the leading viewer.
For navigation and interaction, a hand-held wand with buttons and joystick is used. Position and orientation of this device is also measured by the motion tracking system. The user can, for example, point the wand in the direction of a desired move, rotate the environment via the joystick, or control a virtual beam to select and interact with a virtual object. Compared to other immersive systems, the CAVE operates in "see-through" mode. Users can see physical objects, like their own hands, the other viewers, or equipment brought into the CAVE. Applications can integrate physical objects with the virtual environment. As an example, the mockup of a jet ski is placed inside the CAVE to accommodate the driver and provide the controls for a simulated ride over a virtual lake. Behind the scenes is a cluster of powerful graphics computers that calculates the images and controls all other aspects of a CAVE application in real-time. For optimal perception and smooth navigation, these computers have to re-calculate all images 20 to 30 times per second. A lower frame rate makes the immersive experience jerky and stressful for the viewers. |
| Size | 10' x 10' x 10' |
| Screens | Three walls with rear-projection, one floor with down projection, for a total of four projection screens
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| Projectors | Four Christie Mirage S+4K projectors with mirrors, one for each screen. |
| Resolution | 1024 x 1024 |
| Stereo | Time-sequential projection of stereo images at 120 Hz |
| Glasses | Stereographics' liquid crystal shutter glasses, synchronized via IR (Infra
Red) emitters with projection sequence |
| Input Device | Hand-held wand with three buttons and pressure-sensitive joystick |
| Tracking | Vicon MX system with 8 cameras Optical six degree-of-freedom tracking system |
| Computers |
Four Dell Precision 650 with NVidia 3000G video cards One control computer One tracking computer |
| Sound | Two 100 watt per channel amplifiers with four high fidelity speakers |
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Inspecting a ship's double bottom in the CAVE |
Simulation of a disaster scenario |
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Virtual Football Trainer |
Virtual Jet Ski Driving Simulator |
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Medical Readiness Trainer |
Virtual prototype of Detroit's airport terminal |