Depth cue interaction in telepresence and simulated telemanipulation

Virtual environment displays can show realistic scenes that include a wide variety of visual depth cues. This realism may also elicit telepresence, or the feeling by the viewer that he or she is actually present in the distant or virtual world. For applications such as telerobotics, realistic representations of the remote site may improve task performance. However, timing demands and hardware power may limit the realism that can be achieved. Thus, it is necessary to consider how telepresence affects the operator's task performance. Increasing telepresence may only asymptotically improve performance because of the adaptability of the human operator. In our present experiments, we examined the contribution of two important depth cues, occlusion and disparity, on the performance of a simulated telerobotic task. We have simulated a three-axis tracking task that is viewed under four different levels of realism. We hoped to determine if the combined presentation of the depth cues has a more beneficial effect on performance than either depth cue presented singularly. Results showed similar performance improvements with the presentation of occlusion or disparity individually. When both cues were present together, a somewhat larger performance improvement was measured.