Since Gibson's pioneering work in the 1950s, there has been increasing interest in describing the dynamic visual cues operators extract from the “out-the-window” scene to utilize in vehicular control. Despite this interest, we are still a long way from an adequate understanding of what optical information is utilized, and how the information is integrated into an active control strategy. There are a number of reasons for this apparent shortfalling. First, it is difficult to isolate a candidate optical cue; geometry dictates that several candidate cues will co-vary in any natural scene (e.g., edge rate and flow rate). The experimental isolation of an optical cue often results in visual scenes which are quite unnatural, creating the possibility that strategies used in the experimental setting will not generalize to operational settings. Also, much of the laboratory work has focused on demonstrating people's sensitivity to optical variables, utilizing passive verbal judgments rather than active control paradigms. Whereas the demonstration of sensitivity to an optical cue is a logically necessary step, such a demonstration is not sufficient to verify its utility in an active control task. Further, there is the need for an adequate description of the task demands, allowing a proper mapping between what the controller is trying to achieve and the information available to accomplish the task; no single cue (or set of cues) will be appropriate for all vehicular control tasks. Finally, given the robust and opportunistic nature of the human perceptual system, it is possible that the visual cues used for vehicle control will vary from individual to individual, or even within an individual depending on which cues are available and salient in the control environment. The participants in this panel are well versed in the challenges of studying visually based vehicular control. Their presentations will reflect the lessons learned in this field, as well as insights regarding how current and future research can better realize the promise of this domain.
Available at: http://works.bepress.com/john_flach/116/