Signal timing optimization involves the selection of four basic design elements: phase sequence, cycle length, green split, and offset. None of the available signal timing models is considered adequate to optimize all four design elements, particularly in two-dimensional networks. Among the current models, TRANSYT-7F is most effective for timing, but it does not optimize phasing. Researchers have considered several methods for enhancing TRANSYT-7F to include phasing optimization but thus far no method has proven practical. Genetic algorithms (GAs) are heuristic probalistic search procedures that have been applied to a wide range of engineering problems. The use is investigated of a GA in combination with the TRANSYT-7F optimization routine to select all signal timing design elements. The main purpose of the GA in the proposed scheme is to optimize phase sequences. Two implementations of the GA model are presented.
