A Reuse-oriented Inverse Solution And Extraction Algorithm For NC Machining Planning Information Of Free-form Surface Partition

With the development of modern industries,free-form surfaces are widely used in modern manufacturing industry,and the numerical control(NC)machining technology of related products has higher requirements.The surface morphology of free form surfaces is diverse,and NC machining is difficult,which requires high requirements for NC machining process planning.Reusing the existing NC machining planning examples and drawing on its machining experiences can effectively reduce the difficulty of NC machining planning for free-form surface and improve the machining level.In order to improve the machining efficiency and quality of free-form surfaces with complex shapes,it is often necessary to partition and process them according to their geometric features,and select the corresponding machining methods according to the different features of each zone.The machining planning of this kind of surfaces needs rich machining experience and solid mathematical foundation,and the machining examples also contain more abundant tacit knowledge.In order to fully reuse the NC machining planning example of such curved surface,this paper is based on UG NX software,using secondary development to thoroughly study the machining advantages and reuse methods of such instances.This paper mainly studies the following contents:(1)To avoid tool interference,the methods and significance of free-form surface partitional machining are studied.The identification method of free-form surface NC machining characteristics is proposed,and according to the concept of cutter interference in the curved surface machining,the non-interference zone and easy interference zone divided by the machining curved surface are optimized,and further the specific machining plan of each zone was obtained.Through comparative experiments on partitional machining and non-partition machining,it is proved that sectional NC machining of curved surface can save machining time and improve machining efficiency.(2)This paper studies the kinematics principle of five-axis NC machine tools,and inverse-deduces the calculation formula of the cutter point and the cutter axis vector in the CLSF according to the NC program for three different types of five-axis NC machine tools,which provides the theoretical basis for extracting the surface partition information in the next step.(3)This paper studies the method and principle of NC machining zoning of curved surface by reverse reasoning from NC machining CLSF,and provides reference for the NC machining zoning planning of new and similar curved surface.Further,the relevant NC machining planning information is obtained from the NC machining tool position file in reverse,which provides the theoretical basis and relevant information for the reuse of NC machining information.This paper uses Microsoft Visual Studio 2015(VS2015)as a programming platform,and uses the second development function of UG NX software to achieve the above research.The NC machining simulation experiment of free-form surface was completed in the machining module of UG NX software.Based on the machining time as a reference,the processing efficiency was analyzed and the research results of this paper were verified.