Progression Control Model to Enhance Performance of Transit Signal Priority

Abstract

Transit signal priority (TSP) plays an essential role in reducing traffic jams in a multimodal road traffic environment. Traffic experts expect that the demand for cars will be transferred to buses as the bus-service quality improves. This study proposes a multimodal environment TSP model with dedicated median bus lanes to simultaneously increase bus travel speed at signalized intersections and reduce car delay times. The proposed TSP model includes three optimization stages. The TSP is first optimized using a MAXBAND-based bandwidth model after a partitioned TSP control group is defined relative to a median bus stop to support non-stop bus movement. The optimal combination between these groups is selected using the delay-difference-of-offset technique. A kinematic wave-based offset optimization model is proposed to reduce the car delay time. We analyze the performance of this model in improving two-way bus speeds and reducing the car delay time in Seoul’s bus rapid transit system. The proposed TSP model decreases the stop ratio of buses by analyzing the bus trajectory from the micro-simulation. This model can be used as a center-based control to improve the mobility of buses and cars in a multimodal environment.