Simulation Of Pedestrian Flow In A Bus Based On Cellular Automata And Its Application

Reducing the bus stop time is a key part of improving bus operation efficiency.And the rate of the passengers boarding and alighting affects the bus dwell time.Therefore,bus passengers boarding and alighting behavior is an important part of the study of the bus operation efficiency.Firstly,this paper studies the application of cellular automata in the pedestrian flow in the bus based on the improved dynamic parameter model.The improved model adds cell occupancy parameter and preceding parameter.And each cell has certain characteristics: adjacent cells,cell functions and so on.The improved model considers different situations,which can handle the simulation of complex congestion.According to the actual investigation results,this paper sets the general update rules for the pedestrian flow cellular automata in the bus.Secondly,this paper simulates the passengers getting on and off the bus in Nanchang 245 bus route.By comparing the bus dwell times of four different door layouts and passengers boarding and alighting modes,this article provides some suggestions for bus operation.The simulation results show that when the passengers load factor reaches 70%,the speed of passengers boarding has a significant slowdown,which leads to an increase in the dwell delay of the bus.The Efficiency of passengers alighting the bus is directly related to bus door width.Adjusting the door width can decrease the dwell time of the bus and making exit door flexible can effectively decrease the bus dwell time when there are more passengers on bus.It is found that after adjusting the strategy of the Nanchang 245 bus boarding and alighting models,the dwell time can be decreased by 40%-50% through simulation when there are lots of boarding passengers.The simulation results show that the cellular automaton model has certain practical value,although the shortcoming is that this model only considers the pedestrian flow and effects of other vehicles in the station on the bus dwell time are not studied.Based on the cellular automata model,the bus dwell delay is established,and the existing bus operation scheduling model is modified.Through simulation,phenomenon of buses in different situations is illustrated.Finally,the traditional control method,the bus control method based on the headway and the real-time control method are compared respectively.Through simulation,different control methods are used to determine the stability and efficiency of the bus.Secondly,the cellular automaton model is used to analyze the phenomenon of bus running in different scenarios.The effect of the load rate on the boarding speed of passengers is considered,and then additional delays are caused to the overall dispatch of the bus.The proposed model takes into account the actual operation of the bus Possible conditions and delays,and establish evaluation methods.By simulating the bus operation in three different scenarios,the factors related to the phenomenon of car driving are obtained,and the impact of special circumstances on the car driving,such as the school drop-out,the evening rush hour and the dissipation of large-scale events,are analyzed.Finally,based on the above research,the paper compares the control strategies of bus operations to improve the stability of bus operations.In the end,it is concluded that the control strategy based on the timetable has a certain control effect,but it is difficult to avoid the phenomenon of tandem between the control points;if you increase the control points,it will cause the time of the bus to stay at the control points to increase significantly.The operating efficiency is greatly reduced.The control strategy based on the headway can give the recommended speed of the bus at the control point to increase the speed when the headway with the bus in front increases;otherwise,the bus is decelerated,which compensates for the timetable-based strategy The problem of low driving efficiency is a better control strategy for conventional buses.With the real-time control of buses possible,the real-time control strategy is currently the ideal control strategy.This model uses real-time data to feedback the recommended speed of the bus in real time.The strategy first gives the initial driving speed,which is slightly less than the initial speed of the bus.The maximum speed allows the bus to adjust the distance between the buses by accelerating and improve the stability.