ABSTRACT
An immersive virtual environment (VE) system is an interactive environment in which a user can see and manipulate computer-generated objects in real time (e.g., Barfield and Furness, 1995; Kalawsky, 1993). Such systems are useful for rehabilitation training (Kiryu and So, 2008) and digital prototyping (Burdea and Coiffet, 2003). Typically, when a user moves his/her hands, the positions and orientations of the hands are used to render and update images of virtual hands. However, both the position sensing and rendering procedures take time. Consequently, when users move their hands, they cannot see the correspondingmovements of the virtual hands immediately (So and Griffin, 1991; 1996; So and Chung, 2002). As technology advances, speed improvements should alleviate this discrepancy, but unfortunately, the unrelenting demand for higher resolution, finer colour gradations and lower cost has so far out-paced the advances in computer speed and the time delay problem persists. In this report, the time delay between the moment at which the hand moves and the moment at which the hand image moves is referred to as the “hand-related time delay”.
