Pareto optimal design for offset pattern for coordinated signal control with reduce delay and its analysis

Abstract

In the coordinated signal control of a corridor with 15 signalized intersections, it is found in previous studies that there are a lot of offset patterns to minimize delay time, which is equal to or bigger than the theoretical minimum delay time. The reason why there are a lot of offset patterns is that even if delay time of either one link could be minimized, it is impossible to minimize the adjacent link at the same time, and vice versa. According to the clustering results being converged by similar patterns with the clustering technique proposed in this study, these results have the tendency to give a priority to either direction with direction switching at some intersections. The result suggests the equalization possibility of delay time for both directions along a corridor with changing the direction of priority offset at some intersections. The study proposes an offset pattern search method to take balance of three elements (delay time, number of stops, and directional equality) by the pareto optimum.