locations still appears to be confined to the domain of hazardous operations and to experimental work in the domain of health care. Little consideration is being given to the use of teleoperation to enable individuals who are homebound (e.g., because of physical disabilities or because they are incarcerated) to work at jobs that are located elsewhere and that require substantial interactive sensing and manipulation.
Finally, advances in the technology for telecommunications and teletravel are being accompanied by new ventures in the sex-for-profit business. Unless appropriate societal strictures are imposed, it appears that interactive live audio-video will be heavily exploited for this purpose within the next 2 to 3 years, with equivalent exploitation involving the tactual channel occurring within the next 5 to 10 years.
By definition, human operators constitute a major component of all SE systems. Furthermore, the range of experiences to which the operator is subjected in these systems can be extremely broad. Thus, there are very few topics concerning human behavior (sensorimotor performance, perception, cognition, etc.) that are not relevant to the design, use, and evaluation of SE systems. A number of the modality-specific topics in this general area are discussed in the section below in connection with human-machine interfaces; some of the more general ones are considered here.
One set of such topics focuses on human performance characteristics and includes, for example, sensorimotor resolution, perceptual illusions, information transfer rates, and manual tracking. Knowledge about all of these topics is essential to cost-effective design of SE systems. For example, the limits on human sensory resolution place an upper bound on the resolution required in sensory displays. Similarly, unintentional variability (noise) in motor responses puts an upper bound on the resolution required in control devices. Both sensory input and motor output characteristics are included in human operator models used to interpret performance in various types of manual tracking tasks. And information transfer rates help characterize the operator's ability to receive information via displays, process information centrally, and transmit information via controls. Perceptual illusions can be used to simplify (and thereby reduce the cost of) stimulus generation procedures. If not thought about in advance, however, they can also lead to unexpected failures in performance.
A second set of such factors arises in connection with the alterations in sensorimotor loops that occur when a human operator "drives" an SE system, and the extent to which and the manner in which the human operator adapts to such alterations as a function of his or her experience