The purpose of this report is to identify the information processing bottlenecks that drivers face in specific intersection driving scenarios. These bottlenecks represent situations in which drivers may become overloaded by driving demands, which could result in drivers conducting important driving tasks in improper fashion or skipping certain tasks altogether. To identify and characterize information processing bottlenecks, this report presents a series of task analyses to determine key functions performed by drivers as they approach and navigate through different intersection scenarios. The focus of this task analysis is on identifying the underlying information processing elements, including the perceptual, cognitive, and psychomotor subtasks associated with each individual driving task. Seven distinct driving scenarios were investigated in the task analysis, and each scenario was successively separated into segments, tasks, and subtasks/information processing elements. The scenarios included in the analysis were: (1) left turn on green light, (2) left turn on yellow light, (3) straight on yellow light, (4) straight on green light, (5) right turn on green light, (6) right turn on red light, and (7) stop on red light. Appendix A discusses in detail the equations and assumptions associated with the development of the vehicle timing/dynamics calculations performed for each of the seven driving scenarios included in the effort. (Author/publisher)
Abstract