Research On Multi-source Heterogeneous Data Interconnection Technology Of Typical Production Line Based On OPC UA

With the development of industrial manufacturing technology,the intelligentization of equipment and the interconnection technology between equipment have been paid attention to.At present,various communication protocols among multi-vendor devices and complex heterogeneous data have brought great obstacles to the interconnection between devices.In response to this problem,this paper adopts the OPC UA protocol widely used in industrial communication,takes typical industrial production lines as the object,and studies the three key technologies of industrial data information modeling,efficient transmission,and multi-level transmission.This article mainly includes the following aspects:(1)The scalable information model of typical mechanical equipment based on OPC UA is established.First,the characteristics of the OPC UA information model,the characteristics of the default nodes in the information model and the generation of the address space are analyzed,and the semantics of each node is explored to describe the method of heterogeneous data.Secondly,through the readable graphical representation method and the object-oriented idea,a general model of OPC UA mechanical equipment with both expansibility and portability is established,and the auxiliary equipment set is added to ensure the expansibility of the model.Thirdly,around the scalability of the model,based on the general model,the SCARA robot information system model with rich heterogeneous data is developed.Finally,the model is further expanded,and the welding torch equipment is added to the auxiliary equipment set to expand the specific model of the multi-degree-of-freedom welding robot.(2)Efficient transmission method of industrial heterogeneous data in a typical mobile phone assembly line.First,through data packet capture,the differences in the transmission flow of different data transmission services between the OPC UA server and the client are compared.Secondly,around the typical mobile phone assembly production line,the heterogeneous data of the production line is classified according to the update frequency and data volume,and then the transmission strategy adopted for each type of data is given,and the dynamic adjustment of the OPC UA server according to the current traffic load is proposed.The transmission method of the information release frequency.Finally,taking SCARA that performs a large number of assembly tasks on the production line as the object,a data transmission compression information model is constructed,and the performance of the proposed method is evaluated by simulation experiments.(3)Multi-level heterogeneous data transmission technology.Firstly,the transmission and coding protocols used in OPC UA transmission equipment information model are analyzed,and the characteristics of different protocols are compared to obtain protocol combinations suitable for different working conditions.Secondly,focusing on the heterogeneous data transmission requirements of common industrial equipment,according to the characteristics of the Client/Server model and the Pub/Sub model in the OPC UA technology,each communication module is combined,so that the transmission module has both a large amount of data transmission capability and device interoperability capability..Finally,the researched data transmission modules are combined and applied to the multi-level information interconnection of the factory.(4)Implementation and application display of multi-source heterogeneous data transmission based on OPC UA.First,from the data transmission process,the modules corresponding to the acquisition,transmission and storage of OPC UA technology are realized.Then,the functions of the implemented modules are demonstrated through two application scenarios.Application 1: Monitor the typical mobile phone assembly production line through the OPC UA protocol,collect industrial data of the production line,and store it in the database to form big data.The application fully verifies the effectiveness of each module,and the system composed of multiple modules meets the needs of industrial multi-source heterogeneous data transmission and has good scalability.The second application is to build a virtual device in the Unity software to realize the digital twin of the SCARA device.This application shows that the constructed data transmission system has good performance.