Development Of Metro Train Event Recorder For Multiple Data Sources

In recent years,with the large-scale popularization of urban rail transit in China,the number and operation time of subway trains have grown rapidly.However,subway train accidents due to sudden equipment failure or improper human operation have also shown a gradual upward trend.In order to better investigate the cause of the accident and improve the objectivity and scientificity of the investigation conclusion,some new subway vehicles have begun to install train event recorders.Most of the existing train event recorders rely on imports,and the data sources for collecting records are relatively simple and the number of records is small.In order to increase the diversity of recorded data sources and improve the performance of event recorders,this paper proposes a multi-data source event recorder design scheme for next-generation subway trains,which can not only record multi-channel vehicle signals and human operation status,but also it can communicate with the next-generation train network based on real-time ethernet to acquire and record network communication data.In addition,this paper also attempts to collect and record the car audio and video data on the event recorder for the first time.In this paper,the real-time acquisition of vehicle signals is divided into two independent parts:analog quantity and switch quantity.Firstly,the characteristics of different kinds of signals are analyzed,and the sampling and conditioning circuits are designed in a targeted manner.Secondly,a multi-channel real-time acquisition unit is designed with the Cortex-M series ARM as the core.In order to realize complex network communication and audio and video processing,this paper designs a host unit with embedded industrial computer as the core.Communication with the vehicle signal acquisition unit,real-time communication with the TRDP-based in-vehicle network,and communication with the RTSP-based CCTV system is implemented on the Linux operating system.At the same time,the vehicle signal,the vehicle network data and the real-time audio and video data are recorded separately.In addition,in order to increase the security of data records,this paper also uses DES encryption algorithm to encrypt data files to prevent human tampering,making the data of the event recorder more authoritative.Finally,the PC downloading and analysis software was designed and implemented,and the whole system was verified on the next generation subway demonstration train.The results show that the event recorder designed and developed in this paper can more fully reflect the operating status of key equipment,clearly record various instructions directly generated by human operation and various indirect instructions and data in the vehicle network,and truly display audio and video history screen of the driver’s cab.