Research On Evaluation Method Of Machining Process Based On Digital Twin

With the continuous improvement of the intelligent level of manufacturing industry,the manufacturing mode presents a new change,which puts forward a higher demand for intelligent and efficient process design mode.However,the current manufacturing mode of manufacturing industry is still a one-way execution process of design and manufacturing.It is difficult for the processing site to give timely and effective feedback to the process design.The process design is lack of high fidelity virtual model guidance,and cannot make a rapid and efficient response to the process planning of the processing.Digital twin technology can digitally describe the physical scene,realize the effective management and control of product life cycle data.It provides a new technical direction for the optimization decision of various elements in the processing technology.Therefore,this paper studies the process evaluation method based on digital twin,constructs the process evaluation system based on digital twin,and focuses on the modeling technology of digital twin process model,the organization and management technology of twin data and the process evaluation technology driven by twin data.The followings are the main contents of the thesis:(1)The requirement of process evaluation based on digital twin is analyzedAiming at the requirements and difficulties of 3D process evaluation of complex parts,the dynamic evaluation requirements of machining process and inspection process are analyzed,and the framework of digital twin process model service process is established.Through the acquisition and management of real-time machining data,the mapping and management of machining twin data,the feature expression technology oriented to machining process and the modeling technology of digital twin process model,the digital twin process model service process is constructed Process evaluation process of word twin.(2)The digital twin process model is constructedThe concept of digital twin process model(DTPM)is defined,and the five dimensional architecture of DTPM is described from the process design and execution phase;Through the configuration of processing resources and equipment,the software and hardware are combined to collect real-time data to ensure the high fidelity of the model;The high predictability of the model is realized by virtual simulation;The hierarchical model of machining process data is established,and the twin data is mapped through data analysis;The evolution feature expression model supported by process content,geometric topology information and API is used to realize data circulation and data-driven process dynamic evaluation.(3)The evaluation method of machining process based on digital twin is proposedA process evaluation method based on data word twinning is proposed to evaluate the process scheme,process execution and process parameters.Then,the specific content of key process is evaluated for heavy parts of marine diesel engine.Finally,based on AHP and neural network algorithm,the software is developed with twin data as the basis,machining features as the unit and feature recognition technology as the means The process evaluation based on digital twin is realized on the hardware platform.(4)Independent research and development of the processing technology evaluation systemIn order to realize dynamic process evaluation for machining process,a process evaluation system is developed,which includes three modules: 3D model base management,twin data management and process evaluation.Taking the connecting rod bearing cap,rod body and fuselage of marine diesel engine as the test objects,combined with the monitoring status of the processing process,the digital twin process model of the workpiece is established,and the satisfaction evaluation,process feasibility evaluation and process parameter evaluation of the processing process scheme are respectively carried out,so as to realize the dynamic evaluation and effective output of the process,and verify the effectiveness of the proposed method.