JUDGING PERCEIVED AND TRAVERSED DISTANCE IN VIRTUAL ENVIRONMENTS

The ability to accurately estimate distance is an essential component of navigating large-scale spaces. Although the factors that influence distance estimation have been a topic of research in real-world enviro nments for decades and are well known, research on distance estimation in virtual environments (VEs) has only just begun. Initial investigat ions of distance estimation in VEs suggest that observers are less acc urate in estimating distance in VEs than in the real world (Lampton et al., 1995). Factors influencing distance estimates may be divided int o those affecting perceived distance (visual cues only) and those affe cting traversed distance to include visual, cognitive, and propriocept ive cues. To assess the contribution of the various distance cues in V Es, two experiments were conducted. The first required a static observ er to estimate the distance to a cylinder placed at various points alo ng a 130-foot hallway. This experiment examined the effects of floor t exture, floor pattern, and object size on distance estimates in a VE. The second experiment required a moving observer to estimate route seg ment distances and total route distances along four routes, each total ing 1210 feet. This experiment assessed the effects of movement method , movement speed, compensatory cues, and wall texture density. Results indicate that observers underestimate distances both in VEs and in th e real world, but the underestimates are more extreme in VEs. Texture did not reliably affect the distance estimates, providing no compensat ion for the gross underestimates of distance in VE. Traversing a dista nce improves the ability to estimate that distance, but more natural m eans of moving via a treadmill do not necessarily improve distance est imates over traditional methods of moving in VE (e. g., using a joysti ck). The addition of compensatory cues (tone every 10 feet traversed o n alternate route segments) improves VE distance estimation to almost perfect performance.