Research And Development Of Modular Industrial Data Interactive Terminal Based On OPC-UA

With the advancement of industrial modernization,the demand of data interaction in industrial production line continues to expand.Traditional data interaction terminals are difficult to adapt to the flexible,intelligent and real-time trends under the background of "Industry 4.0".In view of the situation above,industrial data interaction terminal is chosen as the researching object.A data collection and processing platform is designed according to the modularization concept.It realizes scalable data collection,intelligent data interaction and real-time data processing on the production line.Firstly,based on the collection requirements of common industrial signals,an extensible collection module is designed to realize the effective collection of multisource heterogeneous data.Multiple types of signal conversion interfaces are designed to collect data in a unified format.The combination of the custom electrical bus based on the SPI bus and low-voltage differential signal technology constructs a low-latency and high bandwidth data transmission channel.Aiming at the standardized management of data on the bus,a custom binary protocol is proposed.Secondly,in response to the data exchange requirements between the acquisition subsystem and the data management subsystem,a data interaction framework between the coprocessor and the main controller is designed to realize the automatic management of the module by the main controller and open up the data channel from the acquisition module to the user.The coprocessor with no operation system uses interrupt and state machine to switch tasks.The application on the main controller is constructed based on the RT-Linux system and adopts a layered management mode.Thirdly,in order to solve the high latency and high bandwidth occupancy problem of cloud computing,an edge computing framework based on the OPC-UA protocol is designed to solve the deployment and management problems of users' edge computing tasks.Two different computing engines,LUA and MNN,are introduced to the framework to handle edge computing tasks of different computing scales.A task abstraction and instantiation method based on the OPC-UA address space model are proposed to embed the computing engine into the OPC-UA service.Finally,to verify the data collection,data interaction and data processing function of the data interaction terminal designed above,a comprehensive test was designed on a gas filling production line.The result shows that the data acquisition module can realize free combination and connection;the custom bus works stably;the remote data access is safe and reliable;the edge computing program can be easily deployed and executed through the client.All functions meet the expected design goals.