An optimized signal timing of Transit Signal Priority on early green control strategy

Transit Signal Priority(TSP) have been shown to be effective tools for the level of transit service. It gives transit vehicles a little extra green(green extention) or a little less red time(early green) at traffic signals to reduce the delay time. How to maximize the benefit of TSP at isolated intersection is worth to study through extending green time. Some scholars apply the method of delay triangle to calculate the delay time. However, the vehicles arrive or go through the signalized intersection in platoons under the condition of signal coordination for arterials, it is imprecise to use the method of delay triangle to analyse the delay. In this paper, according to the process of vehicles coming and going at intersection, the calculation model of average person delay was proposed by the method of delay parallelogram. A case study was conducted to validate the model results. It is concluded that the method of delay parallelogram provides an effective solution to obtain the optimized signal timing at the intersection.