Discrimination of changes in latency during head movement
Stephen R. Ellis, Mark Young, Bernard D. Adelstein, Sheryl M. Ehrlich · 1999
Human users of environments (VE) are disturbed by system latency which reduces interactivity, user dexterity, and speed. Because latencies in VEs arise from rendering, switching and transmissions delays, they will continue to persist in systems involving satellite or space communication links even as computing speeds increase. Our previous work has focused on the precision, stability, efficiency and complexity of operator interaction in latency-plagued systems (e.g., Ellis, Breant, Menges, Jacoby, & Adelstein, 1997). But there has been relatively little work on users' subjective response to changes in system latency which could cue impending degraded performance and also disturb users' sense of immersion in virtual tasks (see Uno & Slater, 1997). In particular, operators' psychophysical functions describing sensitivity to detection of the visual consequences of latency change have not been measured. We have measured these functions for the first time for head movement while users view nearby objects.