2003 Volume 123 Issue 3 Pages 204-210
This paper describes offset optimization for the fluctuations of traffic flow using a genetic algorithm (GA). An Offset which is the target of signal control parameters for this study is difficult to optimize because of its variety of combinations. Traffic signal optimization using GAs has been investigated in previous studies. Most of them however, focused on signal control without considering the fluctuations of traffic flow. In a practical scene, the rate of flow changes as time passes, so that offset-optimization considering these fluctuations of flow is required. As a case study, an urban traffic route in a city of the Chubu region in Japan, with twenty-one signalized intersections, was tested. To perform offset-optimization by a GA, offset values were represented in a chromosome having the same number of genes as the signals. Two different schemes are introduced into the GA-based program and evaluated in terms of average travel time. The results show that the offset optimization schemes used in this study were valuable for efficient signal control.