VIRTUAL REALITY

(VR) the use of computer modeling and simulation to enable a person to interact with an artificial three-dimensional visual or other sensory environment. VR applications immerse the user in a computer-generated environment that simulates reality through the use of interactive devices, which send and receive information and are worn as goggles, headsets, gloves, or body suits. In a typical VR format, a user wearing a helmet with a stereoscopic screen for each eye views animated images of a simulated environment. The illusion of being there (telepresence) is effected by motion sensors that pick up the user's movements and adjust the view on the screens accordingly, usually in real time (the actual time during which something takes place). Thus, a user can tour a simulated suite of rooms, experiencing changing viewpoints and perspectives convincingly related to his own head turnings and steps. Wearing data-gloves equipped with force-feedback devices that provide the sensation of touch, the user can even pick up and manipulate objects that he sees in the virtual environment. The term virtual reality is also applied to the branch of computer science concerned with the development of such systems. The basis of virtual reality technology emerged in the 1960s in simulators that taught pilots how to fly planes by using head-mounted displays with tracking systems. Virtual reality came of age in the 1980s, when the U.S military and the National Aeronautics and Space Administration began creating new systems for interactive computer-generated imagery. In 1989 the U.S. Department of Defense launched Simnet (simulator network), an experimental network of microcomputer-based workstations that enabled military personnel to practice combat operations on interactive, real-time training systems; Simnet was used to prepare U.S. troops for the Persian Gulf War in 1991. Varying degrees of VR technology are now used in games, exhibits, and sales presentations as well as in aerospace simulators. Virtual reality has potential applications in many different fields, notably entertainment, medicine and biotechnology, engineering, design, and marketing.