Operation Safety Control Of Urban Rail Trains Based On Edge Computing

In the urban rail transit system,the train operation control system is the guarantee for the safe operation of trains.The safety control of urban rail train operation has extremely high requirements for the real-time performance of the train control system.The centralized control mechanism of train operation control system has become a bottleneck restricting the large-scale optimization calculation for the safe and high-density operation of trains,due to the huge data load,long-distance transmission and limited network bandwidth.Compared with the traditional centralized cloud computing,edge computing migrates part or all of the computing tasks to the distributed network edge devices.It has the advantages of real-time data processing and analysis,privacy protection,strong scalability,and less communication traffic.This dissertation builds an edge computing service platform based on an edge computing architecture,which includes two parts: an on-board edge computing device and an edge computing server.At the same time,it designs and implements a safe operation control algorithm for urban rail trains,and at the edge layer realizes the automatic perception of running processes of urban rail trains,and the analysis of the train movement states,to find potential operating hazards,make early warnings in advance,and produce corresponding control strategies.The research contents and results of this dissertation are described as follows.(1)Analyze the requirements and functions of the edge computing service platform,and respectively propose the hardware and software design solutions of the on-board edge computing device,and the software design solutions of the edge computing server.(2)Design and develop on-board edge computing devices.The hardware system of the device is composed of two parts: a communication positioning board and a human-machine interface board,and data transmission between the boards is realized through serial communication.The software system of the device is based on STM32 microcontroller and implemented by C language programming.The communication positioning board mainly has the functions of train satellite positioning and 4G communication between the train and the ground.The human-machine interface board is based on the LVGL(light and versatile graphics library)graphics library for the construction of human-computer interfaces.(3)Design and develop edge computing servers.The software system of the edge computing server is implemented by C# language programming,which mainly includes a human-computer interface module,a communication interface module,a data analysis module,a train dynamic display module,a data storage module,and a train operation status analysis module.(4)Based on the principle of cellular automata and the principle of train operation control under the mobile block system,the safe operation control rules of urban rail trains are proposed,the rule-based train safety control algorithm is designed,and the rule-based model predictive control is designed based on the principle of model predictive control.(5)Test the functions of the on-board edge computing device and the edge computing server.The test results show that all modules of the system can work normally and meet the expected results.Taking the actual data of a subway line at Beijing as an example,the effectiveness of the two safe operation control algorithms for trains was verified through simulation experiments.The calculated reliability of the rule-based train safety control algorithm is about 84.1%,and the reliability of the rule-based model predictive control algorithm is obviously improved.54 Figures,8 Tables,43 References.