NC Tool Path Planning Based On The Subdivision Of Sculptured Surface

Since ancient times,natural stone sculpture because of its inherent physical and chemical properties and unique artistic temperament has been the important components of building environment decoration.In a traditional numerical control processing of stone sculpture,limited to the conditions of complex surface concave of minimum radius of curvature,we use only a small cutter and tool path generation methods for processing,which will result in the repetition and extension of tool path,therefore machining efficiency is reduced.It is unable to meet the needs of the sculpture production.In view of problem of the low stone sculpture processing efficiency,a tool path planning algorithm based on surface subdivision was presented in this paper.The sculptured surface is divided into a series of shape feature has the same or similar surface,and then according to the different regional characteristics we choose different types of processing cutters,and the optimization of process parameters.In similar surface set,we can use the same tool path planning method,as to improve the sculpture on the overall complex curved surface machining efficiency.This paper studies the main contents are:The first,we studied the stone sculpture processing cutters,established the general model of the cutters,studied the types of stone sculpture processing cutters,the selection principle and ball-end cutter geometrical parameters,geometric shapes,established the mathematical model of ball-end cutter blade edge line.The second,the study of the different zoning planning algorithms of sculpture surface.Establish the mathematical model of the sculpture surface,then discrete the sculpture free-form surface;according to the characters of sculpture surface curvature at discrete points,the complex of free-form surface is divided into several the basic surface which easily to process.According to characteristics of the sculpture surface,the surface determined into seven basic surface,flat,concave saddle,concave column,concave ellipsoid,convex saddle,convex column,convex ellipsoid.In the same or similar surface set,we can use the same cutter and tool path generation method.The third,the tool path planning algorithm based on surface subdivision.After the division of different types of surfaces,respectively adopt different processing methods and strategies.In flat surface area,using the large radius of cutter to process,iso-parametric method is used to generate tool path;in surface curvature change steep surface area,using the small radius of cutter to process,iso-scallop method is used to generate tool path.The fourth,the tool path planning algorithm based on surface subdivision simulation experiment research.Using UG software to establish several typical stone sculpture surface,through MATLAB simulation platform,and compared with the traditional single small tool processing schemes comparison and analysis.Simulation experiment results show that the proposed algorithm is better than using only a small cutter and tool path generation method of scheme high machining efficiency,reduced about 18%in the total length of tool path.The method can achieve the goal of improving the efficiency of stone sculpture processing.