Split sequential update signal control based on probe travel time

Abstract

This study develops a method to determine traffic flow conditions at signalized intersections using probe travel time. Then, based on these conditions, a real-time traffic signal control method is developed that sequentially updates signal control parameters such as split times of each traffic signal phase. The proposed method categorizes traffic flow into three states: oversaturated, near-saturated and unsaturated, and these are dealt with state variables. The near-saturated and unsaturated states are distinguished using the green time utilization rate defined in this study. The control method leverages this categorization to make dynamic adjustments that optimize signal timing in response to real-time traffic states. In order to evaluate the effectiveness of this method, a traffic simulation experiment using actual traffic volumes at an actual intersection is carried out. The results show that the proposed signal control method significantly reduces total travel time, demonstrating its potential for reducing traffic congestion in urban areas.