Design And Implementation Of VISSIM Simulation Parameter Calibration System For Urban Road Traffic Based On The Orthogonal Experiment

VISSIM software is the authoritative simulation software in microscopic traffic simulation software.It has a large number of user groups in China.The simulation software can verify or optimize the scheme through simulation,and assist in completing the design of the traffic scheme.There are multiple parameters in VISSIM simulation software that can affect the traffic simulation results.If these parameters are selected unreasonably,it will not be able to achieve a good simulation effect,fail to accurately verify the experimental scheme or the actual traffic situation,and will directly affect the rationality of the design scheme.Therefore,it is necessary for the user to perform parameter calibration.However,VISSIM simulation software does not have a function module for parameter calibration,and users cannot use the simulation software to perform parameter calibration.In order to facilitate the user to calibrate the parameters,a VISSIM parameter calibration system for urban road traffic based on orthogonal test method is designed in this paper.The main work includes:Firstly,the system requirements analysis and system design were carried out.Perform detailed requirements analysis from four aspects: user requirements,functional requirements,non-functional requirements,and development environment.Then,according to the system requirements analysis,the design idea of the calibration system is clarified,and the system is designed according to the functional requirements of the system.Based on this,the specific framework of the system and the overall system implementation process are designed.Secondly,detailed system design work was carried out.From the perspective of system module design,the calibration system is divided into 7 modules: system management module,file management module,simulation module,parameter selection module,parameter calibration module,result analysis module,and data management module.Among them,the parameter selection module adopts the sensitivity analysis method to select the more important parameters in the model as the factors of the orthogonal table;the parameter calibration module uses the orthogonal test method to form the simulation parameter scheme combination,and performs the simulation calibration according to the scheme;the result analysis module passes the average error Function to verify whether the parameter results meet the accuracy requirements,and output the index comparison chart.In order to realize the interaction between the database and the calibration system,the data management module ensures the function of adding,deleting and checking data.Through module function design,working principle design,and work flow design,it provides a basis for the subsequent calibration system implementation.Finally,the system implementation and application work were carried out.C# is used as the main programming language to implement each functional module of the system,and a simulation model is established based on field surveyed traffic data.The system is used to perform parameter calibration on this intersection model.Test results show that the calibration system can achieve the expected design effect.