





The University of North Carolina at Chapel Hill

The Walking Experiment and the Pit A study by Slater, et al., [1995] indicated that naive subjects in an immersive virtual environment experience a higher subjective sense of presence when they locomote by walking-in-place (virtual walking) than when they push-button-fly (along the floorplane). The Pit Room experiment adds real walking as a third condition. Our own studies confirm their findings. We found that real walking is significantly better than both virtual walking and flying in ease (simplicity, straightforwardness, naturalness) as a mode of locomotion. Participants were free to walk around the entire virtual scene in the same manner as in a real environment.

We track the user's head and one hand using a custom optical tracker [Ward, 1992;Welch, 1997]. This tracker works over a range of approximately 10 m by 4 m with millimeter precision. Two optical sensors view blinking infrared LEDs on the ceiling tiles. The tracking system updates position and orientation at approximately 1.5 kHz. Tracking data from a recent experiment is available here. The pit experiment consists of two rooms. A training room environment and stressful environment (pit room). Participants are given the task of picking up balls. They must drop the balls onto their appropriate targets.





We believe the compelling nature of the experience is due to the confluence of many factors: The visual cliff environment itself, the depth of the pit, the narrowness of the ledge

Almost imperceptible end-to-end system lag, on the order of 50 ms

Real walking about in a significant space

The visual fidelity of the detailed, textured, radiosity-lit scene

The excellent resolution and color saturation of the V8 HMD

Stereopsis

The precision and crispness of the tracker

3D spatial audio

The static haptics (the real wooden ledge and the stryofoam walls)



Slater, M., M. Usoh, and A. Steed, 1995: "Taking Steps: The Influence of a Walking Technique on Presence in Virtual Reality," ACM Trans. on CHI,Special Issue on Virtual Reality Software and Technology, 2, 3: 201-219, September. Ward, M., R. Azuma, R. Bennett, S. Gottschalk, and H. Fuchs, 1992: "A demonstrated optical tracker with scalable work area for head-mounted display systems." Proc. of the 1992 Symposium on Interactive 3D Graphics, Computer Graphics 25, 2: 43-52.



Welch, G., and G. Bishop, 1997: "SCAAT: Incremental tracking with incomplete information." Proc. of SIGGRAPH 97, Computer Graphics Proceedings,Annual Conference Series, 1997, 333-344.



