Expert System for Traffic Signal Setting Assistance

Abstract

An experimental knowledge‐based expert system to assist in traffic signal setting for isolated intersections is presented. In contrast to existing computer aids, the system can be applied to intersections of highly irregular geometries. Algorithmic processes to evaluate signal settings and decision tables to identify traffic flow conflicts are invoked by the expert system; phase distribution of flows is performed by applying heuristic rules. The system was written in the OPS5 expert system environment. Advantages and disadvantages of the expert system programming approach relative to conventional algorithmic processes in the traffic engineering domain are described.