Research On Communication Between Central Control And Experimental System Based On Unified Data Model And OPC UA

With people’s increasingly deepening research to space,the necessity of conducting space environment simulation experiments on the ground has become more and more prominent.Therefore,the establishment of a space environment ground simulation device is of great significance.The simulation device mainly includes digital simulation central control system,experimental system and supporting system,etc.The data transmitted between various systems has the characteristics of multi-source and heterogeneous,which is not conducive to the centralized storage and management of data in the device.In addition,there are many types of data transmission equipment in the device,the communication protocol is complicated,the information interaction between the equipment and the system is difficult,and the quality of data transmission is greatly reduced,which seriously affects the stability of the normal operation of the device.Therefore,there is an urgent need for a communication solution with strong interoperability for the ground simulation device of the space environment.This paper mainly focuses on the research of the information interaction between the digital simulation control system and the experimental system,mainly researches the data model construction of the digital simulation central control system,the formulation of the OPC UA communication protocol,the scheme design of integration between the time-sensitive network protocol algorithm and OPC UA communication protocol,gate control scheduling mechanism and simulation verification of the fully centralized network model,etc.The main research work includes following contents:Firstly,the type of data collected by the digital simulation central control system is analyzed,a uniform data model is constructed which fulfils the requirements of the digital simulation central control system,the meaning and format of the fields are defined and explained in the uniform data model;in order to verify the applicability of the uniform data model constructed by this paper,the content meaning and coding mode of the uniform data model are analyzed in the general scene of industrial data collection;a data conversion scheme of the non-uniform data model is designed for the data information that cannot be obtained directly in the closed device.Secondly,in order to improve the communication interoperability between the digital simulation central control system and the experimental system,the OPC UA specification was used to describe the data of the space environment ground simulation device,and the corresponding relationship between the OPC UA information model and the uniform data model is analyzed;the Ua Modeler tool is used to construct the information model of the space environment ground simulation device,and the x-ray Photoelectron Spectrometer(xps)type equipment is used as an example to verify the rationality of the information model construction method in the space environment ground simulation device;in order to analyze the efficiency of the information model based on the OPC UA specification in the information communication process,the mapping from OPC UA communication protocol to ethernet protocol is realized,the protocol efficiency of OPC UA communication protocol is calculated,and its efficiency is compared with Modbus / TCP protocol.Thirdly,to enhance the transmission quality of time-sensitive data,the time-sensitive network technology is introduced into the proposed information interaction architecture.Through the theoretical analysis of time-sensitive network,it is proved that time-sensitive network technology can effectively improve the real-time performance of information transmission.In order to realize the application of time-sensitive network technology in the information interaction architecture of space environment ground simulator,a fusion scheme of time-sensitive network technology and OPC UA communication protocol is proposed,the corresponding data transmission mechanism is adaptively configured.Finally,in order to verify the feasibility of the proposed network interaction architecture in the space ground simulation device,an OPNET experimental model is built,and the pipeline priority Algorithm based on gate-control mechanism and the configuration scheme of centralized network model are simulated.And the quality of the network model of the space environment ground simulator is analyzed.