Viewpoint Optimisation for Virtual Environment Navigation Using Dynamic Tethering - A Study of Tether Rigidity

Abstract

Much research has been carried out on providing navigational aids and improving users' wayfinding ability across a variety of navigation related tasks. In this study, we focus on investigating users' navigational performance with respect to the display frame of reference in a large scale virtual environment. Dynamic viewpoint tethering is proposed as a means to improve user control and reduce the need for mental rotations, thus facilitating the acquisition of configurational knowledge about the virtual space. The modelling of dynamic viewpoint tethering is explained and recent research findings are presented. Twelve volunteers participated in an experiment in which they were instructed to control an aircraft-shaped cursor flying through a set of virtual tunnels (local guidance) and to answer questions about the environment (global awareness). Experimental results showed that neither the very loose dynamic tether nor the completely rigid tether supported the best control performance. Rather, an optimal tether configuration lies at the centre of the rigidity continuum. Research results are discussed from the point of view of design of navigational system interfaces.

Effects of Viewpoint Displacement on Navigational Performance in Virtual Environments

“…As a framework for constraining viewpoint behaviour in navigational display systems, viewpoint tethering has been proposed in recent years as a means of integrating information from both egocentric and exocentric frames of reference (McCormick et al, 1998;Colquhoun & Milgram, 2000;Wang & Milgram, 2001;2002;2003). The concept of viewpoint tethering encompasses a display design technique that involves using a tether for virtually "attaching" the display viewpoint to an avatar.…”

“…Wang & Milgram (2001) extended the experimental domain into 3D and, in a virtual tunnel navigation scenario, they found that tethered displays supported superior tracking performance relative to both ego-and exo-centric displays. In follow-up studies, Wang & Milgram (2002;2003) contrasted tethered displays with different dynamic properties and showed that a critically damped dynamically tethered display resulted in the best guidance performance. In the study reported here, efforts have been focused on investigating the effect of viewpoint viewing distance, in terms of the tether length, on both local guidance and global awareness performance in a navigational scenario.…”