188宝金博页面版

Computer-Aided Design 62 (2015) 64–77Contents lists available at ScienceDirectComputer-Aided Designjournal homepage: www.elsevier.com/locate/cadA flexible and effective NC machining process reuse approach forsimilar subpartsRui Huang ∗ , Shusheng Zhang, Changhong Xu, Ximao Zhang, Congcong ZhangThe Key Laboratory of Contemporary Designing and Integrated Manufacturing Technology, Ministry of Education, Northwestern Polytechnical University,Xi’an, 710072, Chinah i g h l i g h t s• A feature-based parameter-driven model to guide NC process reuse is established.• The NC process parameter-driven characteristic of similar feature is revealed.• An NC process reusability assessment approach of similar pocket/subpart is proposed.• We extend feature-based NC process reuse to a greater granularity of subpart.a r t i c l e i n f oArticle history:Received 8 January 2014Accepted 27 October 2014Keywords:Feature-based machiningReusability assessmentInheritance mechanismNC machining process reusea b s t r a c tNC machining process reuse is widely accepted as an effective strategy for engineers to generate the pro-cess plan with less time and lower cost. However, there has been very little research on how to reuse theNC machining process of similar subparts. As a result, most reusable NC machining process still has to re-main in the repository as tacit knowledge, which can easily get lost due to oblivion. This paper proposes anovel NC machining process reuse approach for similar subparts in which existing NC machining processcasesaredescribedinassociationwithmachiningfeatures.First,afeature-basedparameter-drivenmodelis established to formalize the links between information imbedded in the machining feature and the pa-rameters of cutting tools, drive geometries, and machining strategies. Then, the NC process parameter-drivencharacteristicofsimilarfeatureisrevealedfromtheperspectiveofmachininggeometry,machiningprecision of the feature, and cutter geometry. Moreover, an NC process reusability assessment approachof similar pocket/subpart is presented using the pocket’s medial axis transform. Finally, the NC machiningprocess inheritance mechanisms are explored to implement the NC machining process reuse automati-cally and efficiently. A prototype system based on CATIA has been developed to verify the effectivenessof the proposed approach.© 2014 Elsevier Ltd. All rights reserved.1. IntroductionWith increasingly competitive environment for manufacturingenterprises, engineers are often challenged to design the NC ma-chiningprocess(calledNCprocessforsimplicity)ofapartwithlesstimeandlowercost[1].Todealwiththischallenge,afeasiblestrat-egy is to reuse the NC process of similar subparts in the repositoryas effectively as possible [2]. Here, a subpart of a 3D CAD modelis composed of a set of machining features on a part model, whichmayappearindifferent3DCADmodels.Inmaturedmanufacturingenterprises, similar subparts are usually machined with similar NC∗Corresponding author. Tel.: +86 29 88460357; fax: +86 29 88491576.E-mail address: huangrui053469@163.com (R. Huang).processes, which indicate that there exists a large amount of NCprocesses that can be reused. In recent years, the content-based3D CAD model retrieval has become an active research topic and alot of work has been done [3,4], which provides a novel enablingtool to locate the similar subparts for reusing their NC processes infiner manner. However, most of the related works have focused onsearching the similar subparts, not dealing with how to reuse theexisting NC process of the retrieved similar subpart. Consequently,current NC process reuse approaches still rest on the level of sim-ilar subparts discovering, and the retrieved similar subparts areprimarily taken as a reference for NC process reuse, which reliesheavily on the experience and knowledge of engineers.Today, computer-aided design (CAD), computer-aided manu-facturing (CAM), and computerized numerical control (CNC) tech-nologies have been widely used in machining complex parts, anda huge number of 3D CAD models with NC processes (also calledhttp://dx.doi.org/10.1016/j.cad.2014.10.0040010-4485/ © 2014 Elsevier Ltd. All rights reserved.提出了一种灵活有效的相似零件数控加工过程重用方法