Research On Regional Coordinated Bus Priority Signal Control Considering Pedestrian Delay

With the development of cities and the acceleration of urbanization,the traffic demand of urban residents is increasing,and the traffic congestion and pollution in big cities are becoming more and more serious.In order to solve the urban traffic problem and relieve the huge pressure on the urban road network,our country has put forward the public transport priority development strategy,which requires to develop urban public transport,encourage residents to travel by public transport,and improve the public transport sharing rate.Bus priority signal control is one of the important methods of bus priority,which can provide priority for the bus to pass through the signal intersection,so that the bus can go through the intersection without stopping,and the bus delay can be reduced.In order to further optimize the bus priority signal control,this dissertation optimizes the existing bus priority signal control method from point,line and surface levels,and proposes a bus priority signal control method considering pedestrian delays.This method explores the impact of pedestrian delays on the signal timing adjustment scheme and the priority control effect,and seeks to minimize the impact of priority signals on pedestrian traffic while ensuring bus priority traffic.At the same time,in order to reduce urban traffic pollution,this dissertation not only studies delays but also vehicle emissions,analyses the emissions of different vehicles at intersections,and proposes a regional bus priority signal control method that integrates delays and emissions,so as to minimise system delays and emissions when implementing bus priority,and promote the sustainable development of the transport system.The content of this dissertation mainly includes the following aspects:(1)The bus priority signal control method for isolated intersection considering pedestrian delay is proposed.In this dissertation,the consideration of pedestrians crossing the street is added to the conventional considerations,and the pedestrian delay variation model under different priority strategies is proposed to discuss the influence of pedestrian delay on the bus priority signal control scheme and control effect.This dissertation studies three strategies: green light extension strategy,red light early termination strategy and phase insertion strategy.By comprehensively analyzing the delay variation of bus passengers,social vehicle passengers and pedestrians under different priority control strategies,the multiobjective optimization model are established with the goal of maximizing the delay reduction.Multi-objective genetic algorithm(Gamultiobj),multi-objective particle swarm optimization(MOPSO)and CPLEX are used to solve the problem,and the optimization results of three algorithms are compared to obtain different signal timing optimization schemes under various priority strategies.In order to discuss the optimization effect of the model,some numerical examples are analyzed.The results of the example show that the bus priority signal control considering pedestrian delay proposed in this dissertation can ensure the pedestrian crossing rights and interests as much as possible while giving priority to buses,and greatly reduce the pedestrian crossing delay at intersections.In addition,this dissertation also studies the priority request response scheme and the specific signal timing optimization scheme at an isolated intersection under various priority request scenarios.(2)The bus priority signal control method under arterial coordinated signal control is proposed.Taking the green light extension strategy and the red light early termination strategy as examples,the bus priority signal control is carried out for two adjacent intersections,and six situations of bus and social vehicles traveling between intersections under these two priority strategies are discussed.According to the delay variation of bus passengers,social vehicle passengers and pedestrians in six situations,the multi-objective optimization models are established respectively.Then the optimization effects of the model in peak and non-peak period are discussed through the example analysis.In this dissertation,three algorithms,multiobjective genetic algorithm(Gamultiobj),multi-objective particle swarm optimization(MOPSO)and goal attach method(Fgoalattain)are used to solve the optimization model.The optimized bus priority signal control schemes are obtained by comparing the solution speed and results of the three algorithms.The results show that the proposed method can effectively reduce pedestrian delay,and the optimization effect in peak period is better than that in nonpeak period.In addition,this dissertation also discusses the situation that there are multiple bus priority requests in the main traffic direction,and proposes the signal timing optimization scheme when there are multiple bus priority requests in peak and non-peak periods.(3)The regional bus priority signal control mehtod considering pedestrian delay is proposed.This dissertation takes several intersections in the area as the research object and proposes the regional bus priority signal control method considering pedestrian delay.This control method is divided into two stages.The first stage is the coordinated signal control at regional intersections.The signal timing optimization model is established according to the vehicle travel characteristics in the region and the delay of social vehicle passengers and pedestrians.Then the basic signal timing scheme at each intersection is obtained by solving the model.The second stage is bus priority signal control based on basic signal timing scheme.Taking the green light extension strategy as the example,the bus travel situations between intersections are analyzed.The delays of bus passengers,social vehicle passengers and pedestrians under different conditions are calculated respectively,and then the bus priority models are established with the goal of minimizing regional delay.In order to discuss the optimization effect of the model and the influence of pedestrians on the priority control scheme,a small area surrounded by four intersections is selected as an example for case analysis.The case analysis results show that the control method considering pedestrian delay proposed in the first stage can reduce a large number of pedestrian delays,but will slightly increase the social vehicle passenger delay,so that the total delay of the system is reduced.Since the signal optimization has been carried out at the first stage,the delay reduced at the second stage is not obvious,but the method proposed at the second stage can still reduce more pedestrian delay.In addition,this dissertation also discusses various situations in which there are multiple priority requests in the region,and establishes delay models for optimization for various situations.The case analysis results show that since the first bus priority control has optimized the signal timing scheme,when the area needs to extend the green light for the second time,the adjustment range of the second green light extension scheme is relatively small,and the system delay variations are also small.(4)The regional bus priority signal control considering system delays and vehicle emissions is proposed.In order to avoid increasing vehicle emissions during bus priority signal control,this dissertation proposes a regional bus priority signal control method that comprehensively considers system delays and vehicle emissions from the perspective of system comprehensive benefits.A multi-objective optimization model is established by calculating regional delays and the emissions of different vehicles(fuel vehicles and electric vehicles).Then genetic algorithm is used to solve the model.In order to discuss the impact of vehicle emissions on the priority control scheme and optimization effect,some examples are used for analysis.The results show that the method proposed in this dissertation can reduce vehicle carbon emissions without excessively increasing delays,which is beneficial to reducing urban traffic pollution.As the proportion of electric vehicles increases,vehicle emissions have a greater impact on the bus priority signal control scheme.When the proportion of electric vehicles is 100%,the optimization results with and without considering vehicle emissions have the largest difference.In addition,by converting delays and emissions into economic values,it is found that the value of emissions reduction can be greater than the value of increased delay time by the bus priority control method that considers vehicle emissions,which indicates that it is meaningful to consider vehicle emissions when conducting bus priority control.