Research On Machining Path Optimization Method Of CNC Machine Tools Based On Digital Twin

As one of the most important equipments of intelligent manufacturing,CNC machine tools are developing in the direction of intelligence,precision and networking.At present,CNC machining generally has the problem that the total machining time is too long and the machining efficiency is low.The ratio of the movement time of the tool and the work piece to the total machining time is as high as 70%.Therefore,optimizing the tool path can not only improve the machining efficiency of CNC machine tools,but also reduce the machining cost.What is more,because the running state of CNC machine tool is not static,it should be considered in the machining path optimization.Digital twin provides an effective solution to the problem for machining path optimization by real-time monitoring and simulating the running state of physical space CNC machine tool.In this paper,aiming at shortening the machining stroke of CNC machine tools so as to improve machining efficiency and reduce machining time,the application of digital twin method in tool path optimization is deeply studied.The main research contents are as follows:(1)Research on the modeling method and key technologies of digital twin CNC machine tools.Through three-dimensional modeling and model simplification,the 3D virtual model of digital twin CNC machine tools is constructed.Aiming at the problem of machining path optimization,the motion model,machining data perception and semantic interaction technology of digital twin CNC machine tools are studied,which realize the digital twin machine tools with physical drive and virtual control.(2)Based on the model of digital twin CNC machine tools,the interactive and integrated machining path optimization method of CNC machine tools is studied from three aspects with mathematical modeling,optimization algorithm,digital twin data-driven simulation and case verification.In the aspect of mathematical modeling,according to the machining characteristics of CNC machining,a mathematical model is carried out.For optimization algorithm,the improved genetic annealing optimization algorithm is proposed to improve its accuracy and ability.In the aspect of simulation and case verification,a machining path optimization method based on digital twin is proposed,which continuously updates the machining state of digital twin CNC machine tools through real-time perceptual data,so that the digital twin CNC machine tools can adjust the original machining path in time.Finally,a case study is given to verify the method.(3)Designing and developing an interactive and integrated digital twin system of CNC machine tools.The tool of Jena is used to parse ontology model,then through the listener,the real-time machining information can be obtained.By the technology of WebGL,the three-dimensional model is embed into the system.Through dynamic visualization of three-dimensional model and real-time virtual simulation in Semantic Web,the system provides machining monitoring and optimization services that can be acquired anytime and anywhere,including information management services,CNC machine tools monitoring services,perceptual data management services,machining simulation services.