Wednesday, May 21, 2008

Virtual Reality History

images.nintendolife.com
The concept of virtual reality has been around for decades, even though the public really only became aware of it in the early 1990s. In the mid 1950s, a cinematographer named Morton Heilig envisioned a theatre experience that would stimulate all his audiences’ senses, drawing them in to the stories more effectively. He built a single user console in 1960 called the Sensorama that included a stereoscopic display, fans, odor emitters, stereo speakers and a moving chair. He also invented a head mounted television display designed to let a user watch television in 3-D. Users were passive audiences for the films, but many of Heilig’s concepts would find their way into the VR field.
Philco Corporation engineers developed the first HMD in 1961, called the Headsight. The helmet included a video screen and tracking system, which the engineers linked to a closed circuit camera system. They intended the HMD for use in dangerous situations -- a user could observe a real environment remotely, adjusting the camera angle by turning his head. Bell Laboratories used a similar HMD for helicopter pilots. They linked HMDs to infrared cameras attached to the bottom of helicopters, which allowed pilots to have a clear field of view while flying in the dark.
In 1965, a computer scientist named Ivan Sutherland envisioned what he called the “Ultimate Display.” Using this display, a person could look into a virtual world that would appear as real as the physical world the user lived in. This vision guided almost all the developments within the field of virtual reality. Sutherland’s concept included:
A virtual world that appears real to any observer, seen through an HMD and augmented through three-dimensional sound and tactile stimuli
A computer that maintains the world model in real time
The ability for users to manipulate virtual objects in a realistic, intuitive way
In 1966, Sutherland built an HMD that was tethered to a computer system. The computer provided all the graphics for the display (up to this point, HMDs had only been linked to cameras). He used a suspension system to hold the HMD, as it was far too heavy for a user to support comfortably. The HMD could display images in stereo, giving the illusion of depth, and it could also track the user’s head movements so that the field of view would change appropriately as the user looked around.

Tuesday, May 20, 2008

Uses of Virtual Reality




In the early 1990s, the public's exposure to virtual reality rarely went beyond a relatively primitive demonstration of a few blocky figures being chased around a chessboard by a crude pterodactyl. While the entertainment industry is still interested in virtual reality applications in games and theatre experiences, the really interesting uses for VR systems are in other fields.
Some architects create virtual models of their building plans so that people can walk through the structure before the foundation is even laid. Clients can move around exteriors and interiors and ask questions, or even suggest alterations to the design. Virtual models can give you a much more accurate idea of how moving through a building will feel than a miniature model.
Car companies have used VR technology to build virtual prototypes of new vehicles, testing them thoroughly before producing a single physical part. Designers can make alterations without having to scrap the entire model, as they often would with physical ones. The development process becomes more efficient and less expensive as a result.
Photo courtesy of Atticus Graybill of Virtually Better, Inc.Using virtual therapy to treat a patient’s fear of flying.Virtual environments are used in training programs for the military, the space program and even medical students. The military have long been supporters of VR technology and development. Training programs can include everything from vehicle simulations to squad combat. On the whole, VR systems are much safer and, in the long run, less expensive than alternative training methods. Soldiers who have gone through extensive VR training have proven to be as effective as those who trained under traditional conditions.
In medicine, staff can use virtual environments to train in everything from surgical procedures to diagnosing a patient. Surgeons have used virtual reality technology to not only train and educate, but also to perform surgery remotely by using robotic devices. The first robotic surgery was performed in 1998 at a hospital in Paris. The biggest challenge in using VR technology to perform robotic surgery is latency, since any delay in such a delicate procedure can feel unnatural to the surgeon. Such systems also need to provide finely-tuned sensory feedback to the surgeon.
Another medical use of VR technology is psychological therapy. Dr. Barbara Rothbaum of Emory University and Dr. Larry Hodges of Georgia Tech University pioneered the use of virtual environments in treating people with phobias and other psychological conditions. They use virtual environments as a form of exposure therapy, where a patient is exposed -- under controlled conditions -- to stimuli that cause him distress. The application has two big advantages over real exposure therapy: it is much more convenient and patients are more willing to try the therapy because they know it isn't the real world. Their research led to the founding of the company Virtually Better, which sells VR therapy systems to doctors in 14 countries.


Addicts are being treated through Virtual Reality

www.boeing.com

flyawaysimulation.com

Virtual Reality and Flight Simulators

Monday, May 19, 2008

HMD (Head Mounted Display)

www.eri.harvard.edu

A typical HMD has either one or two small displays with lenses and semi-transparent mirrors embedded in a helmet, eye-glasses or visor. The display units are miniaturised and may include CRT, LCDs, Liquid Crystal on Silic

on (LCos), or OLED.
www.jvrb.org

CAVE (Cave Automatic Virtual Environment)




http://cb.nowan.net/blog/tag/virtual-reality/

The CAVE is a theatre that sits in a larger room . The outside room must be free of light at all times while using the CAVE. The walls of the CAVE are made up of rear-projection screens, and the floor is made of a down-projection screen. High-resolution projectors (the University of Illinois uses an Electrohome Marquee 8000) display images on each of the screens by projecting the images onto mirrors which reflect the images onto the projection screens.

http://cb.nowan.net/blog/tag/virtual-reality/

(c) S. Kuntz

The user will go inside of the CAVE wearing special glasses to allow for the 3-D graphcs that are generated by the CAVE to be seen. With these glasses, people using the CAVE can actually see objects floating in the air, and can walk around them,http://cb.nowan.net/blog/tag/virtual-reality/

Panoscope (c) Laval Virtual

getting a proper view of what the object would look like when they walk around it. This is made possible with electromagnetic sensors. The frame of the CAVE is made out of non-magnetic stainless steel in order to interfere as little as possible with the electromagnetic sensors. When a person walks around in the CAVE, their movements are tracked with these sensors and the video adjusts accordingly. Computers control this aspect of the CAVE as well as the audio aspects. There are multiple speakers placed from multiple angles in the CAVE, giving one not only 3-D video, but 3-D audio as well.

http://en.wikipedia.org/


Sunday, May 18, 2008

Set ups for CAVE's

© Arnaud Muthelet
Four walls and a floor

A Wall © Arnaud Muthelet
One large wall


A Reality Center © Arnaud Muthelet
Semi-circular wall





An HoloStage © Arnaud Muthelet
Rear projection with one wall and a floor



Friday, May 16, 2008

360 Degree Light Display

www.taylortheteacher.com


blog.tmcnet.com

A bit reminisent of Star Wars technology




http://www.geekologie.com/2007/08/360_degree_light_field_display.php



The display consists of a high-speed video projector, a spinning mirror covered by a holographic diffuser, and circuitry to decode specially rendered video signals. Rendering over 5,000 images per second of interactive 3D graphics, projecting 360-degree views.