Research On Digital Twin Monitoring System During Milling Of Large Bearing Block

In the milling process of large bearing housing,the tool stiffness is low relative to the workpiece,and it is easy to cause chatter.Larger vibration will make the tool function is less than the workpiece,cannot remove material,serious can make the tool embed artifacts caused both scrap,at the same time,due to programming errors or error will make the tool collision or the handle and artifacts or workbench,it might damage the machine parts in machine tools machining precision is reduced,leading to economic losses and casualties.Therefore,chatter monitoring and tool bump protection in milling process are very important topics.In view of the above problems,this paper introduces the digital twin technology to build a digital twin monitoring system.The main research contents are as follows:Firstly,the overall scheme of digital twin virtual system is designed.Combined with the actual parameters of the machine tool,UG is used as a 3D model building tool to establish a 3D model and 3d Max is used for rendering;Using Unity 3D to build the digital twin virtual system,the virtual machine tool change function,NC code analysis function,posture control and other functions are designed and developed.Secondly,the dynamic milling force model and rigid parts milling dynamics model are established.The modal parameters and milling force coefficients are obtained by experimental method,and then the stability lobe diagram is established.According to the stability lobe diagram,cutting parameters of the stable boundary are selected for milling experiments and the acceleration signals are measured.According to the acceleration signals,the adaptive monitoring threshold of the digital twin monitoring system is obtained by function fitting.Thirdly,the overall data acquisition scheme is proposed for the acquisition of the position,speed,acceleration and other signals of the machine tool spindle,and OPC UA protocol and Lab VIEW are used to collect the above signals.Based on the digital twin technology,the anti-collision technology and chatter alarm technology are proposed to guide the actual machining.In this paper,the driver update database based on My SQL database is proposed to update the digital twin virtual system model.Finally,according to the system requirements,the UI interface development,respectively developed the login interface,the main interface,each function interface.Real-time mapping test of machine tool physical state and spindle flutter warning and alarm test are carried out for digital twin monitoring system.Test the data transmission of the database to ensure the data transmission.