Applying simulation to highway intersection design

Abstract

This paper describes a simulation model of driver- vehicle behaviour at an intersection and two versions (one batch, one interactive) of its implementation. The model offers the user considerable flexibility in specifying the intersection, the traffic control techniques, and the volume and other characteristics of the traffic. It incorporates some of the latest findings of human factors research concerning the driving task, and represents the driver's perceptual, decision-making, and response processes as the driver approaches, passes through, and leaves the intersec tion. Driver behaviour is based on various percep tual cues and on psychophysical judgements derived from them. We rejected gap-acceptance distribution as the basis for driver behaviour at the intersection because we formulated the model for intersection design. vali dation tests showed that the model created gap- acceptance data statistically equivalent to field data. Two implementations of the conceptual model have been built. They are modular in design and are programmed in FORTRAN because of its transportability and proven efficiency in use of CPU time and of memory for traffic simulation. The batch-mode version runs on any computer having a FORTRAN IV compiler; it has already been used successfully in the complete rede sign of an old intersection. The interactive version runs on a minicomputer with a graphics display; it is being considered for driver re-education.