Bus Dwell Time Modeling And Simulation Base On Cellular Automata

With the expansion of the number of vehicle,the problem of traffic congestion has become a serious challenge for many cities.Prioritizing the development of public transportation and improving the utilization rate of road resources is one of the effective ways to alleviate traffic congestion.As a transportation system with large capacity,low consumption and high efficiency,bus transport mode occupies an extremely important in the urban transportation system.However,the phenomenon of bus delay and non-punctuality greatly affects the travel efficiency of residents.Accurately predicting the bus service time to improve the bus service level is a key factor in attracting residents to choose buses.Based on the service time of bus stops,this paper uses field investigation and dynamic theory modeling as the main technical means to reveal the individual characteristics,behavior characteristics and movement laws of passengers on the bus,establishing a floor field model of passenger boarding and alighting movement that can be applied to the optimization design of bus stops and bus interiors,and strive to achieve accurate prediction of passenger boarding and boarding time and optimization of bus service efficiency.The main work is as follows:(1)Characteristic analysis and prediction of passengers’boarding and alighting time.Design a reasonable and effective research plan based on the actual situation.The field survey found that the position of standing passengers on the bus is related to the attraction of the area and facilities in the bus to passengers,and it is also related to the degree of crowded surrounding passengers.In addition,the crowdedness of passengers on the bus is one of the main reasons that make it difficult to accurately predict the average boarding time.According to field observation and data analysis,the changing trend of boarding time is consistent with the BPR function(Bureau of Public Roads,1964).For this reason,this paper uses the BPR function to fit the actual data,and obtains a function formula that can effectively reveal the quantitative relationship between the average passenger boarding time and the number of passengers on the bus.Data analysis shows that the goodness of fit of the formula R~2 is 0.8475,so the calibrated BPR function can accurately predict the average passenger boarding time.(2)Establishing CA evolution model of boarding and alighting movement.Based on the in-depth analysis of the distribution and movement of passengers on the bus in the previous part,in order to better show the mobility preferences of passengers on the bus,on the one hand,the static floor field is used to show the attractiveness of different locations on the bus to passengers;on the other hand,In order to overcome the limitation of pedestrian following motion in the dynamic floor field of the traditional pedestrian flow model,innovatively introduce the repulsive force between passengers into the dynamic floor field.Combining the field data analysis and the basic properties of the cellular automata model,reasonable simulation parameters and motion evolution rules are abstracted,and the dynamic floor field and the static floor field are coupled to propose a domain model that can accurately describe the behavior of passengers boarding and alighting.After many simulations and using field data to identify the model,the optimal parameters of the model were determined according to the numerical analysis,and then the actual data was used to verify the model after identification,which finally proved the reliability and practicability of the model.(3)Simulation research on the influencing factors of passengers boarding.Based on the dynamic evolution simulation model built above,the efficiency of passengers boarding and alighting is numerically simulated in terms of platform scale,passenger distribution on the bus,and internal structure of the bus.The simulation results show that the scale of the platform,the distribution of passengers on the bus,and the seat layout will all have a significant impact on the efficiency of passengers boarding and alighting.Based on this,the internal structure layout optimization plan of the bus and the platform guidance management and control strategy are proposed,and the service level of the bus at the station is evaluated through the identified simulation model.The results show that the proposed strategy can significantly improve the operational efficiency of bus stops.