Datensatz

Zusammenfassung

In Virtual Reality, subjects typically misperceive visually simulated turning angles. The literature on this topic reports inconclusive data. This may be partly due to the dierent display devices and eld of views (FOV) used in these studies. Our study aims to disentangle the specic in uence of display devices, FOV, and screen curvature on the perceived turning angle for visually simulated ego-rotations. In Experiment 1, display devices (HMD vs. curved projection screen) and FOV were manipulated. Subjects were seated in front of the screen and saw a star eld of limited lifetime dots on a dark background. They were instructed to perform simulated ego-rotations between 45 and 225 using a joystick to control the rotation of the image. In a within-subject design, performance was compared between a projection screen (FOV 86 64), a HMD (40 30), and blinders that reduced the FOV on the screen to 40 30. Generally, all target angles were undershot. We found gain factors of 0.74 for the projection screen, 0.71 for the blinders, and 0.56 for the HMD. The reduction of the FOV on the screen had no signicant eect (p=0.407), whereas the dierence between the HMD and blinders with identical FOV was signicant (p<0.01). In Experiment 2, screen curvature was manipulated. Subjects performed the same task as in Experiment 1, either on a at projection screen or on a curved screen (radius 2m, FOV 86 64 for both). Screen curvature had a signicant eect (p<0.001): While subjects turned too far on the at screen (gain 1.12), they did not turn far enough on the curved screen (gain 0.84). Subjects' verbal reports indicate that rotational optic ow on the at screen was misperceived as translational ow. We conclude the following: First, display devices seem to be more critical than FOV for simulated ego-rotations, the projection screen being superior to the HMD. Second, screen curvature is an important parameter to be considered for simulation of ego-motion in virtual reality.