Development Of One-dimensional Simulation Software Package For Urban Train Longitudinal Collision

Urban rail transit is an important daily transportation tool for citizens due to its precise timeliness,economy and environmental protection.With the rapid development of urban rail transit,its safety issues have also received more attention.Train safety technology is divided into active safety technology and passive safety technology.Active safety technology is a preventive method for accidents.It can reduce the probability of accidents by developing advanced control system,signal system and detection system.However,the actual operation environment of trains is far more complex than that in the experimental conditions.Even with the advanced active safety technology,accidents cannot be completely avoided.Advanced train passive safety technology is still needed to reduce casualties and property losses when accidents occur.The energy-absorbing structure of train,which consists of buffer,crush tube,anti-climbing device and energy absorbing area of car body,is the key factor to affect the passive safety performance of the train.As the only recoverable element in the train energy-absorbing structure,buffer plays a dual role in ensuring the smooth and comfort of daily operation and absorbing collision energy.It is an important part in the train energy-absorbing structure,and its performance parameters are very important.In order to verify the performance parameters of the buffer,a one-dimensional simulation software package for urban train longitudinal collision is developed in this paper,which provides a simple and fast calculation tool for buffer manufacturers in the verification of the performance parameters of energy absorbing structures such as buffer.Based on urban trains,the working principle of the energy-absorbing structure of the train is studied,the force output characteristics of the energy-absorbing structure in the longitudinal collision process are analyzed,and the mathematical expression model of the longitudinal force of the energy-absorbing structure in the longitudinal collision process and the set of differential equations of the longitudinal dynamics of the train group are established.Then,based on the mathematical model of energy-absorbing structure and the vehicle dynamics equation,the design and development of one-dimensional simulation software package for longitudinal collision of train are carried out on MATLAB software platform.According to the input and output requirements of parameters in the simulation calculation process,the human-computer interaction interface of the software package is designed by the GUIDE tool in MATLAB,and the parametric modeling and fast calculation of the simulation process of urban train longitudinal collision are realized.Finally,the calculation results of the software package developed in this paper are verified.By comparing and analyzing the results of software package and SIMPACK under the same calculation parameters,the validity of the results of software package calculation is proved.