Development Of Production Data Acquisition System For Knitting Machine Compatible With OPC UA Specification

With the continuous development of computer technology and communication technology,as well as the concept of "Industry 4.0",all walks of life are facing the problem of digital transformation.Some achievements have been made in the development of intelligent equipment and industrial digitalization in the textile field,which can not be separated from the support of production data.However,due to the variety of knitting equipment,the heterogeneity of parameters and communication protocols often leads to the problems of semi-structuring and fragmentation of data in the information interaction of knitting equipment,thus forming "information islands".The cross-platform characteristics of OPC UA technology can meet the needs of unified communication among devices.However,due to technical limitations and cost considerations,OPC UA technology is not well used in equipment clusters with low automation degree.Therefore,this paper takes round weft machine as the research object and designs a set of production data acquisition system for round weft machine which is compatible with OPC UA specification.Based on the in-depth analysis of the production situation and intelligent demand of the circular latitude locomotive,the overall architecture of the system is divided into four layers: the device layer,the cloud service layer,the visualization layer and the OPC UA Server layer.In this paper,an information model of round weft machine based on OPC UA specification is established.Attribute set is used as the carrier of round weft machine production data and a database is designed to store round weft machine production data.An OPC UA data gateway is proposed,and an information exchange scheme of circular weft machine is designed based on communication data frame.A communication service program for information exchange,decoding and storage is developed.The application software running on Web and mobile terminal is designed to realize the visualization of production data and the control of production activities.The server of OPC UA is set up to make the production data of round weft machine open to the external client of OPC UA,and provide a unified data interface and interconnection operation scheme for the production management of round weft machine.After between circular weft knitting enterprises locomotive in comprehensive experiment,results show that this system can complete the real-time production data collection of circular knitting machine and the production data visually presented to users,at the same time the user can also to control the production and management,and this system can provide standardized service interface,in conformity with the OPC UA standard to some extent,improved the knitting enterprise informatization intelligent level,also provides a reference knitting machinery to achieve interconnectivity.