Research On Tool Adaptation And Process Parameter Optimization In Part Machining

To solve the problems of high production cost and low manufacturing efficiency caused by tool preparation,labor cost and cutting experiment cost,as well as conservative selection of process parameters,computer technology and information technology have been integrated deeply into tool manufacturing enterprises with many cutting service software and platform have been developed to provide online technical support for users.These software products save the cost and time of tool adaptation and cutting trial to some extent.However,most of the existing platforms were developed by giant tool companies,and their business mainly focuses on the realization of single feature tool adaptation and process optimization,which cannot respond to the demand which requires complete solutions for the full cutting process of multi-feature parts.Therefore,to improve the intelligent level and expand its service ability of the tool service platform,provide the whole cutting process of end user with a complete solution where the global optimization of the tool and process scheme can be carried out,so that the tool application enterprises can be released from the tedious task of tool adaptation from massive product data and the suitable process parameters exploration.This paper provides a set of methods for machining feature recognition,feature available tool adaptation,tool integrated adaptation for multiple features and process optimization,and the corresponding network platform is also developed to provide a complete solution for the whole cutting process of parts.The main research contents include:(1)The data structure of CAD model file in STEP format has been researched to obtain the geometric and topological elements contained in the model,and the methods for external normal vector of surface elements and judge the concavity of intersecting edges have also been provide to obtain the machinability of the machine features.In addition,a predefined feature library is constructed,so that the basic features can be recognized based on the attribute adjacency matrix matching.Moreover,a complex feature recognition method based on matter-element model is proposed,by means of hierarchical association information between matter-element,the expression of correlation between basic features and complex features is realized,and the geometric constraints of tool adaptation of complex features can be obtained,these methods solve the interface problem between complex feature recognition and tool adaptation.Compared with the current feature recognition based on learning algorithm,this method can provide adaptation constraints of available cutting tools with machining features,and can be better integrated with tool adaptation,process optimization and other parts cutting links.(2)To solve the problem of tool adaptation with identified features,an empirical knowledge processing technology based on fuzzy method is proposed,which realized the acquisition,integration and reuse of empirical knowledge from knowledge sources such as domain experts and operation manuals,and established a knowledge base of cutting tool adaptation.The adaptation method of feature available tools based on production rules is studied,and the rule base of correlation relationship among cutting elements such as machining requirements,machine tool information,workpiece material and machining feature size is also established.The range of characteristic values of available tools is obtained by rule reasoning.The tool brand database is established based on ISO13399,and the tool adaptation across suppliers is realized through the standardized tool characteristic expression.(3)The multi-feature tool comprehensive adaptation model under the network environment is proposed,and the evaluation system of multi-feature tool comprehensive adaptation under the network environment is constructed.The model of tool integrated adaptation for multiple features is established,which is constrained by cost,taking into account efficiency,environment and user preference to form the comprehensive utility value.The intelligence level and business ability of tool service platform has been enhanced.To realize the adaptive solution of the model,a precision convergence factor is introduced into the evolutionary game algorithm,so that it can efficiently process a large number of product data from many tool brands.The motorcycle crankshaft mainly manufactured by turning processing and square test piece mainly manufactured by milling processing are studied as cases to prove the feasibility of proposed methods.(4)To provide solution for comprehensive optimization of whole cutting process,taking into account processing efficiency,manufacturing cost and environment,a comprehensive optimization model for the whole cutting process of parts is proposed.Aiming at the problem of multiple model variables and high coupling degree between variables,a solution method driven by multi-objective particle swarm optimization algorithm and leapfrog algorithm is proposed.Compared with the current process optimization technology oriented to single feature,the integrated optimization method of parts process proposed in this paper can focus on the whole cutting process of parts and realize global optimization of cutting process based on user preferences.(5)An online platform is developed according to the proposed methods to provide tool adaptation and comprehensive cutting process optimization.In particular,the interactive interface is developed based on J Query,Bootstrap and Vue progressive frameworks,distributed management of knowledge rules and data management system based on Spring Cloud framework is also developed.Finally,taking the square specimen of a manufacturing factory as a case to verify the practicability of the developed platform.The cutting experiments are carried out with the process parameters of whole cutting process obtained from the developed platform and the factory,respectively.The results show that the processing quality of the two experiments both meet the processing requirements,however,the application of the platform can not only adapt the cutting tool scheme to the whole cutting process of parts efficiently and cost-friendly,but also the optimization process provided by the platform can significantly improve the overall processing efficiency and reduce the comprehensive cost with the carbon emissions considered.It is proved that the development of the platform has certain engineering practical significance.