Study On Microscopic Simulation Model Of Pedestrian Crossing In The Urban Road Environment

In urban road environment,pedestrian crossing behaviors are affected by vehicles,road facilities and surrounding environment.The interactions between pedestrians and vehicles are unavoidable.A micro-simulation system of pedestrian-vehicular traffic flow in urban road environment for China is constructed.On the one hand,establishing the pedestrian microscopic simulation model in urban road environment expands and enriches the research of social force model.On the other hand,the simulation model is established to lay the foundation for establishing traffic simulation system.The simulation model provides a convenient and effective tool for safety evaluation of road facilities and traffic control schemes.At Hongqi street and Gongnong Road interaction,Tongzhi Street and Ziyou road intersection,Xi’an road and Chongqing Road intersection,Chongqing Road,Renmin street intersection and the selected section of Yatai Street,the speed,acceleration and position of pedestrian and vehicle were obtained by using video data extraction software.Then,the characteristics of pedestrian crossing are studied first based on the data obtained.According to the pedestrian crossing characteristic analysis,the positions of pedestrian crossing obey the Weibull distribution.The bi-directional pedestrian’s crossing speeds increase first after the bidirectional pedestrians meeting each other,and reduce after separating from each other.Then,by using the traffic wave theory and drag focre theory,the pedestrian crossing time model is established.After the analysis,it is found that the distribution of the illegal pedestrian trajectories is concentrated,and the distributions of pedestrian crossing positions in three crossing areas obey the Weibull distribution.Then,a model of overflow pedestrian trajectory distribution was established,and the influencing factors of pedestrian trajectory were obtained.Based on the study of pedestrian crossing characteristics,the pedestrian crossing behaviors in urban road environment are modeled.This paper first modeled the pedestrian flow without interference by using the social force model.The pedestrian microscopic simulation model proposed in this paper takes the following behavior,random fluctuation behavior,conflict avoidance behavior between pedestrians and path planning behavior.The extended models are established for these behaviors,and the calibration method of the model parameters is proposed.The extended models were validated,and the simulated pedestrian crossing speed,crossing time,crossing tractory and pedestrian velocity-density relation were compared with the actual data,and the models were validated.Then,the pedestrian behaviors in the relatively complex road environment were studied.In unmarked road sction,pedestrian crossing is less affected by vehicles and external factors(such as crosswalk line and signal lights),therefore,this paper studied first the interactions between pedestrians and vehicles on unmarked road sction.Considering the influences of vehicle on pedestrian crossing behaviors on the unmarked road sction,this paper puts forward the extended social force model,which includes pedestrian’s stopping decision model,avoiding vehicle model,vehicle’s following model and lane line’s force model for vehicle,and introduces the process and method of model establishment in detail.Then,based on a large number of actual observational data,the maximum likelihood estimation method is used to calibrate the parameters of the model.Then the simulation model is validated by comparing the mean and variance of speeds and velocity distribution of pedestrians and vehicles.The model is validated from microscopic to macroscopic.Finally,the model is extended to be applied in more complex road environments(signalized intersections).At signalized intersection,the movements of pedestrians are affected by road facilities and signal control,so the model in fourth chapter can not been applied.Based on the model in the fourth chapter,the pedestrian simulation model is extended by considering the behavior of signal control,crosswalk line and pedestrian crossing and avoiding right-turning vehicles.The model of the desired position distribution of pedestrians at signalized intersections,the force model acted by the crosswalk,the stop/go decision model and the avoiding model are established.Then,the social force model of the right-turning vehicle is established,the basic social force model of the motor vehicle is extended to the right-turning vehicles simulation model for the intersection environment.In order to provide a guidance for the movement of the right-turning vehicles,the trajectory model of the right-turning motor is established.Finally,the behavior of pedestrian movement,vehicle-pedestrian conflict and trajectory distribution are analyzed,and the validity of the model is validated from macroscopic to microscopic.On the basis of the above research,a countermeasure restraining pedestrian to overflow is put forward,and the effect of the measures is analyzed by using the field experiment and simulation experiment.