The intersection advisor is a prototype expert system that recommends geometric modifications to improve intersection operation. It complements existing microcomputer programs that consider the other two aspects of intersection design, volumes and signalization. Intersection advisor is intended for eventual incorporation in a comprehensive, interactive intersection design package. M.1, A knowledge-based expert system development tool, was used to develop the intersection advisor to run on ibm or ibm-compatible microcomputers. During an interactive consultation the advisor requests information on the intersection volumes, critical movements, geometry, and constraints on approach improvement. It then recommends the most efficient improvements for each approach by generating one of nearly 600 possible reports. Recommendations are arrived at by determining an "ideal" laneconfiguration for the given traffic flows. The ideal design is checked against the improvement constraints, and a next-best design is selected, if necessary. The best feasible design is then compared with the existing design, and the user is informed of any modificationsrequired. Intersection designs produced with the advisor compare well with those produced using the guidelines of the 1985 highway capacity manual. This paper appeared in transportation research record no. 1145, Expert systems for transportation applications. For covering abstract see IRRD no 817754.
Abstract