Authors: Azzedine Boukerche, Shervin Shirmohammadi, Abu Hossain
Addresses: PARADISE Research Laboratory, School of Information Technology and Engineering, University of Ottawa, Ottawa, Canada. ' Distributed Collaborative Virtual Environments Laboratory, School of Information Technology and Engineering, University of Ottawa, Ottawa, Canada. ' PARADISE Research Laboratory, School of Information Technology and Engineering, University of Ottawa, Ottawa, Canada
Abstract: Haptic Collaborative Virtual Environments, like other collaborative environments, are adversely affected by the inherent network lag, caused by delay, jitter, or packet loss, when users are geographically distributed. In this paper, we propose an approach based on both decorators and prediction to compensate for network delays and lost updates. Our approach adds to existing networking-level techniques a history buffer, and a decorator-based predictor at the receiving side and can improve the quality of collaboration as perceived by the remote users. The predictor can determine lost-update messages to improvise the current state, guess the current network delay, and anticipate remote user|s interaction strategy and virtual object|s position/orientation based on the history, while the decorator will act as a visual cue to inform the user about current network conditions such as the amount of lag experienced; this allows the user to cope with the lag from a human-machine interface point of view.
Keywords: telehaptics; synchronous collaboration; distributed virtual environments; collaborative environments; haptics; decorators; prediction; network delays; lost updates; human-machine interface; network lag.
International Journal of Computer Applications in Technology, 2007 Vol.29 No.1, pp.81 - 88
Published online: 14 Jun 2007 *Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article