Navigating through large virtual environments using a headmounted display (HMD) is difficult due to the spatial limitations of the tracking system. We conducted two experiments to examine methods of exploring large virtual spaces with an HMD under translation conditions different than normal walking. Experiment 1 compares locomotion in the virtual environment using two different motor actions to translate the subject. The study contrasts user learning and orientation of two different translational gains of bipedal locomotion (not scaled and scaled by ten) with joystick locomotion, where rotation in both locomotion interfaces is accomplished by physically turning. Experiment 2 looks further at the effects of increasing the translational gain of bipedal locomotion in a virtual environment. A subject’s spatial learning and orientation were evaluated in three gain conditions where each physical step was: not scaled, scaled by two, or scaled by ten (1:1, 2:1, 10:1, respectively). A sub-study of this experiment compared the performance of people who played video games against people who did not.

This article examines the degree to which knowledge about the body’s orientation affects transformations in spatial memory and whether memories are accessed with a preferred orientation. Participants learned large paths from a single viewpoint and were later asked to make judgments of relative directions from imagined positions on the path. Experiments 1 and 2 contribute to the emerging consensus that memories for large layouts are orientation specific, suggesting that prior findings to the contrary may not have fully accounted for latencies. Experiments 2 and 3 show that knowledge of one’s orientation can create a preferred direction in spatial memory that is different from the learned orientation. Results further suggest that spatial updating may not be as automatic as previously thought.

There is currently much research activity involving virtual environments (VEs) and spatial behavior (spatial perception, cognition, and performance). After some initial remarks describing and categorizing the different types of research being conducted on VEs and spatial behavior, discussion in this paper focuses on one specific type, namely, research concerned with the use of VE technology for training spatial behavior in the real world. We initially present an overview of issues and problems relevant to conducting research in this area, and then, in the main portion of the paper, present an overview of the research that we believe needs to be done in this area. We have written this paper for the forum section of PRESENCE because, despite its length, it is essentially an opinion piece. Its aim is not to report the results of research in our own laboratory nor to review the literature; other papers that fulfill these functions are already available in other articles. The primary purpose of this paper is to stimulate discussion about needed future research. In general, we believe that open discussion of research that needs to be done can serve the research enterprise as much as discussion of completed work. 1.

A relatively simple architectural space was modeled and used to compare the effects of spatial training in simulations versus training in the real world. Thirty-five subjects were trained in one of the following conditions: real world (RW), virtual environment (VE), nonimmersive virtual environment (NVE), and model (Mod). The VE condition made use of a head-mounted display to view the simulated environment, while the NVE condition used a desktop monitor. In the Mod condition, the subject viewed and could manipulate a 3-D model of the space, viewed from a desktop display. The training -transfer tasks, performed after brief unstructured exposure to the actual space or to one of the simulations, consisted of estimating the bearing and range to various targets in the real space from various spatially distributed stations, each such pair of estimates constituting a subtask of the overall transfer task. Results obtained from each of the four training conditions proved to be roughly the same. Training in any one of the simulations was comparable to training in the real world. Independent of training condition, there was a strong tendency among subjects to underestimate range. Variability in range errors was dominated by differences among subjects, whereas variability in bearing errors was dominated by differences among subtasks. These results are discussed in the context of plans for future work. 1

We compared four different methods of travel in an immersive virtual environment and their effect on cognition using a between-subjects experimental design. The task was to answer a set of questions based on Crook’s condensation of Bloom’s taxonomy to assess the participants ’ cognition of a virtual room with respect to knowledge, understanding and application, and higher mental processes. Participants were also asked to draw a sketch map of the testing virtual environment and the objects within it. Users ’ sense of presence was measured using the Steed-Usoh-Slater Presence Questionnaire. Our results suggest that for applications where problem solving and interpretation of material is important, or where opportunity to train is minimal, then having a large tracked space so that the participant can physically walk around the virtual environment provides benefits over common virtual travel techniques.

We describe a between-subjects experiment that compared four different methods of travel, and their effect on cognition and paths taken in an immersive virtual environment (IVE). Participants answered a set of questions based on Crook’s condensation of Bloom’s taxonomy that assessed their cognition of the IVE with respect to knowledge, understanding and application, and higher mental processes. Participants also drew a sketch map of the IVE and the objects within it. Users’ sense of presence was measured using the Steed-Usoh-Slater Presence Questionnaire. Participants’ position and head orientation were automatically logged during their exposure to the virtual environment. These logs were later used to create visualizations of the paths taken. Path analysis, such as exploring the overlaid path visualizations and dwell data information, revealed further differences among the travel techniques. Our results suggest that for applications where problem solving and interpretation of material is important or where opportunity to train is minimal, having a large tracked space so that the participant can walk around the virtual environment provides benefits over common virtual travel techniques.

this paper, we examine the role of the VE's visual fidelity and the role of several cognitive characteristics of the user in enabling configurational (or "survey") knowledge of a computer-simulated large-scale maze. Configurational spatial knowledge is characterized by knowledge of the overall pattern of spatial relationships in an environment and is operationally defined here as skill at pointing and estimating distances to unseen locations from any place in an environment. It is generally assumed that increasing the fidelity of a VE will result in improvements in its training effectiveness. When VE's are used to train perceptual and motor skills, this principle is likely to be true (Hunt & Waller, 1999). For example, Witmer and his colleagues showed that a relatively high-fidelity VE (with a head-tracked stereoscopic immersive display) resulted in more accurate and faster traversal of a complex real-world route than did training with a map (Witmer, Bailey, Knerr, & Parsons, 1996). Similarly, Loomis and his colleagues showed that Spatial representations of virtual mazes p. 3 increasing the fidelity of the VE interface (by including kinesthetic and vestibular input) significantly improved the accuracy of people's memory about short paths that they had recently traversed (Chance, Gaunet, Beall, & Loomis, 1998; Klatzky, Loomis, Beall, Chance, & Golledge, 1998). It is important to realize that route memory of the type studied by Witmer et al., and by Loomis et al. is largely mediated by perceptual and motor processes and generally does not require one to form a flexible mental representation of the global characteristics of an environment (i.e., configurational knowledge). The acquisition of configurational knowledge is generally considered to be a controlled process, re...

ABSTRACT: We describe some of the results of our program of basic and applied research on navigating without vision. One basic research topic that we have studied extensively is path integration, a form of navigation in which perceived self-motion is integrated over time to obtain an estimate of current posilion and orientation. In experiments on pathway completion, one test of path integration ability, we have found that subjects who are passively guided over the outbound path without vision exhibit significant errors when attempting to return to the origin but are nevertheless sensitive to turns and segment lengths in the stimulus path. We have also found no major differences in path inlegration ability among blirid and sighted populations. A model we havc developed that attributes errors in path integration to errors in encoding the stimulus path is a good beginning toward understanding path integration performance. In otber research on path integration, in which optic flow information was manipulated in addition to the proprioceptive and vestibular information of nonvisual locomotion, we havc found that optic flow is a weak input to the path integration process. In other basic research, our studies of auditory distance perception in outdoor environments show systematic underestimation oC sound source distance. Our applied research has been concerned with developing and evaluating a navigation system for the visually impaired that uses three recent technologies: the Global Positioning System, Geographic Information Systems, and virtual acouslics. Our work shows that there is considerable promise of these three technologies in allowing visually impaired individuals to navigate and learn about unfamiliar environments without the assistance of human guides. (Optoni Vis Sci 2001;78:282-289)

Three experiments investigated spatial orientation in a virtual navigation task. Subjects had to adjust a homing vector indicating their end position relative to the origin of the path. It was demonstrated that sparse visual flow was sufficient for accurate path integration. Moreover, subjects were found to prefer a distinct egocentric or allocentric reference frame to solve the task. “Turners” reacted as if they had taken on the new orientation during turns of the path by mentally rotating their sagittal axis (egocentric frame). “Nonturners,” by contrast, tracked the new orientation without adopting it (allocentric frame). When instructed to use their nonpreferred reference frame, both groups displayed no decline in response accuracy relative to their preferred frame; even when presented with reaction formats based on either egoor allocentric coordinates, with format unpredictable on a trial, both groups responded highly accurately. These findings support the assumption of coexisting spatial representations during navigation.

Navigation is the most common interactive task performed in three-dimensional virtual environments (VEs), but it is also a task that users often find difficult. We investigated how body-based information about the translational and rotational components of movement helped participants to perform a navigational search task (finding targets hidden inside boxes in a room-sized space). When participants physically walked around the VE while viewing it on a head-mounted display (HMD) then they performed 90 % of trials perfectly, comparable to participants who had performed an equivalent task in the real world during a previous study. By contrast, participants performed less than 50 % of trials perfectly if they used a tethered HMD (move by physically turning but pressing a button to translate) or a desktop display (no body-based information). This is the most complex navigational task in which a real-world level of performance has been achieved in a VE. Behavioral data indicate that both translational and rotational body-based information are required to accurately update one’s position during navigation, and participants who walked tended to avoid obstacles even though collision detection was not implemented and feedback not provided. A walking interface would bring immediate benefits to a number of VE applications.