BRENT EDWARD INSKO: Passive Haptics Significantly Enhances Virtual Environments (Under the direction of Frederick P. Brooks, Jr.) One of the most disconcertingly unnatural properties of most virtual environments (VEs) is the ability of the user to pass through objects. I hypothesize that passive haptics, augmenting a high-fidelity visual virtual environment with low-fidelity physical objects, will markedly improve both sense of presence and spatial knowledge training transfer. The low-fidelity physical models can be constructed from cheap, easy- to-assemble materials such as styrofoam, plywood, and particle board.

The ability of robots to autonomously perform tasks is increasing. More autonomy in robots means that the human managing the robot may have available free time. It is desirable to use this free time productively, and a current trend is to use this available free time to manage multiple robots. We present the notion of neglect tolerance as a means for determining how robot autonomy and interface design determine how free time can be used to support multitasking, in general, and multirobot teams, in particular. We use neglect tolerance to 1) identify the maximum number of robots that can be managed; 2) identify feasible configurations of multirobot teams; and 3) predict performance of multirobot teams under certain independence assumptions. We present a measurement methodology, based on a secondary task paradigm, for obtaining neglect tolerance values that allow a human to balance workload with robot performance.

Large wall-sized displays are becoming prevalent. Although researchers have articulated qualitative benefits of group work on large displays, little work has been done to quantify the benefits for individual users. We ran two studies comparing the performance of users working on a large projected wall display to that of users working on a standard desktop monitor. In these studies, we held the visual angle constant by adjusting the viewing distance to each of the displays. Results from the first study indicate that although there was no significant difference in performance on a reading comprehension task, users performed about 26% better on a spatial orientation task done on the large display. Results from the second study suggest that the large display affords a greater sense of presence, allowing users to treat the spatial task as an egocentric rather than an exocentric rotation. We discuss future work to extend our findings and formulate design principles for computer interfaces and physical workspaces.

Redirected Walking, a new interactive locomotion technique for virtual environments (VEs), captures the benefits of real walking while extending the possible size of the VE. Real walking, although natural and producing a high subjective sense of presence, limits virtual environments to the size of the tracked space. Redirected Walking addresses this limitation by interactively and imperceptibly rotating the virtual scene about the user. The rotation causes the user to walk continually toward the furthest wall of the lab without noticing the rotation. We implemented the technique using stereo graphics and 3D spatialized audio. Observations during a pilot study suggest that the technique works: Redirected Walking causes people to change their real walking direction without noticing it, allows for larger VEs, and does not induce appreciable simulator sickness. 1.

Previous results have shown that users perform better on spatial orientation tasks involving static 2D scenes when working on physically large displays as compared to small ones. This was found to be true even when the displays presented the same images at equivalent visual angles. Further investigation has suggested that large displays may provide a greater sense of presence, which biases users into adopting more efficient strategies to perform tasks. In this work, we extend those findings, demonstrating that users are more effective at performing 3D virtual navigation tasks on large displays. We also show that even though interacting with the environment affects performance, effects induced by interactivity are independent of those induced by physical display size. Together, these findings allow us to derive guidelines for the design and presentation of interactive 3D environments on physically large displays.

... In this article we present four experiments comparing the performance of users working on a large projected wall display to that of users working on a standard desktop monitor. In these experiments, we held the visual angle constant by adjusting the viewing distance to each of the displays. Results from the first two experiments suggest that physically large displays, even when viewed at identical visual angles as smaller ones, help users perform better on mental rotation tasks. We show through the experiments how these results may be attributed, at least in part, to large displays immersing users within the problem space and biasing them into using more efficient cognitive strategies. In the latter two experiments, we extend these results, showing the presence of these effects with more complex tasks, such as 3D navigation and mental map formation and memory. Results further show that the effects of physical display size are independent of other factors that may induce immersion, such as interactivity and mental aids within the virtual environments. We conclude with a general discussion of the findings and possibilities for future work.

The literature often suggests that proprioceptive and especially vestibular cues are required for navigation and spatial orientation tasks involving rotations of the observer. To test this notion, we conducted a set of experiments in virtual reality where only visual cues were provided. Subjects had to execute turns, reproduce distances or perform triangle completion tasks: After following two prescribed segments of a triangle, subjects had to return directly to the unmarked starting point. Subjects were seated in the center of a half-cylindrical 180° projection screen and controlled the visually simulated ego-motion with mouse buttons. Most experiments were performed in a simulated 3D field of blobs providing a convincing feeling of self-motion (vection) but no landmarks, thus restricting navigation strategies to path integration based on optic flow. Other experimental conditions included salient landmarks or landmarks that were only temporarily available. Optic flow information a...

Abstract—Navigation is an essential element of many remote robot operations including search and rescue, reconnaissance, and space exploration. Previous reports on using remote mobile robots suggest that navigation is difficult due to poor situation awareness. It has been recommended by experts in human–robot interaction that interfaces between humans and robots provide more spatial information and better situational context in order to improve an operator’s situation awareness. This paper presents an ecological interface paradigm that combines video, map, and robotpose information into a 3-D mixed-reality display. The ecological paradigm is validated in planar worlds by comparing it against the standard interface paradigm in a series of simulated and realworld user studies. Based on the experiment results, observations in the literature, and working hypotheses, we present a series of principles for presenting information to an operator of a remote robot. Index Terms—3-D interface, augmented-virtuality, human– robot interaction, information presentation, teleoperation, USAR-

(c) VisBlocks � tiled high-resolution display module. Physically large-size high-resolution displays have been widely applied in various fields. There is a lack of research, however, that demonstrates empirically how users benefit from the increased size and resolution afforded by emerging technologies. We designed a controlled experiment to evaluate the individual and combined effects of display size and resolution on task performance in an Information-Rich Virtual Environment (IRVE). We also explored how a wayfinding aid would facilitate spatial information acquisition and mental map construction when users worked with various displays. We found that users were most effective at performing IRVE search and comparison tasks on large high-resolution displays. In addition, users working with large displays became less reliant on wayfinding aids to form spatial knowledge. We discuss the impact of these results on the design and presentation of IRVEs, the choice of displays for particular applications, and future work to extend our findings.

We introduce and present preliminary results for a hybrid display system combining head-mounted and projector-based displays. Our work is motivated by a surgical training application, where it is necessary to simultaneously provide both a high-fidelity view of a central close-up task (the surgery) and visual awareness of objects and events in the surrounding environment. In particular, for trauma surgeons it would be valuable to learn to work in an environment that is realistically filled with both necessary and distracting objects and events. In this paper, we motivate the use of a hybrid display system, discuss previous work, describe a prototype along with methods for geometric calibration, and present results from a controlled human subject experiment. 1.