Showing papers on "Augmented reality published in 1991"
11 Nov 1991
TL;DR: A predictive Kalman lter was designed to compensate for the delay in orientation data, and an anisotropic low pass low pass approach was devised to reduce the noise in position data.
Abstract: The Polhemus Isotrak is often used as an orientation and position tracking device in virtual reality environments. When it is used to dynamically determine the user's viewpoint and line of sight ( e.g. in the case of a head mounted display) the noise and delay in its measurement data causes temporal-spatial distortion, perceived by the user as jittering of images and lag between head movement and visual feedback. To tackle this problem, we rst examined the major cause of the distortion, and found that the lag felt by the user is mainly due to the delay in orientation data, and the jittering of images is caused mostly by the noise in position data. Based on these observations, a predictive Kalman lter was designed to compensate for the delay in orientation data, and an anisotropic low pass lter was devised to reduce the noise in position data. The e ectiveness and limitations of both approaches were then studied, and the results shown to be satisfactory.
237 citations
01 Mar 1991
TL;DR: Virtual reality systems Virtual Reality on Five Dollars a Day Virtual reality on Five dollars a Day
Abstract: Virtual reality systems Virtual Reality on Five Dollars a Day
91 citations
26 Sep 1991
TL;DR: Virtual reality is generally regarded as a next-generation human-computer interface as discussed by the authors and has been included in research projects for many years now, and until recently has remained a back-room curiosity.
Abstract: Virtual reality is generally regarded as a next-generation human-computer interface. Even so, virtual reality has been included in research projects for many years now, and until recently has remained a back-room curiosity. Virtual image displays such as aircraft head-up displays have been available since the 1950s. The defence establishments have been investigating visually coupled systems (now known as virtual reality) for many years, unfortunately very little information is in the public domain. Technology has matured to a point where fairly cheap systems can now be assemble-this has led to quite major claims being made by the various equipment suppliers. Recent press releases both in newspapers and on television have attracted the public's imagination. It has been speculated that very large sums of money are available for the exploitation of virtual reality systems. Unfortunately, the practicalities of real engineering has resulted in serious limitations of the technology. In order to create virtual reality, these technology limitations must be understood and overcome. Whatever solution is eventually derived, it must fully address the complex human factors related issues. >
7 citations