Research On The Method Of Continuous Smooth Path Planning For Surface Processing And Other Residuals

The development of modern CNC system and CNC machine tools and the maturity of CAD and CAM software have not only improved the processing quality and efficiency of mechanical parts,but also made great progress in complex shape and surface processing technology.Components with complex surfaces are widely used in vehicle,ship,aerospace,mold,artificial skeleton and other fields.For a long time,there have been some problems in NC machining of complex surfaces,such as insufficient surface processing quality and long processing time.In the machining of parts with complex surfaces in space,tool path development,path optimization,interference processing and simulation processing have always been the focus and difficulty of modern high-speed and high-precision NC machining technology.This paper introduces various NC tool path planning methods in recent years,analyses their advantages and disadvantages,and explores a smoother tool path which is more suitable for high-speed machining.For the first time,a path planning method for continuous smoothing of space complex surface with equal residual is proposed.The corresponding path planning and G code generation software are developed,which can smoothly and efficiently plan tool path for complex space surface.The dense discrete cutter location data points are obtained by the trajectory planning algorithms such as 'equal cross-section intersection method','equal distance cutter location calculation method','equal chord length spiral generation method'.Then the cutter location data points are interpolated and fitted by cubic triangular interpolation spline curve,so that each cutter location is smoothly connected,and the continuous smooth machining path with equal residual is obtained.Trajectory planning algorithm can effectively reduce tool lifting times,rapid movement,acceleration and deceleration,pause and large angle direction transformation in the process of machining,and reduce the residual amount of machining surface,so as to reduce the impact and vibration of machine tools,prolong tool life and improve the micro-smoothness of machined surface.Based on the trajectory planning algorithm for continuous smoothing of space surface and using Visual Fox Pro database language,this paper develops an automatic planning software for continuous smoothing of equal residual machining path,which realizes the integration process from three-dimensional data processing of STL model to path planning,and then to G code output of NC program.In order to ensure the reliability of the machining process,MATLAB is used to verify the three-dimensional graphics output of tool path before the actual machining experiment,and CIMCO software is used to simulate the cutting process before the actual machining.The path planning method for continuous smoothing of spatial surfaces with equal residual can be applied not only to simple convex and concave surfaces,but also to complex multi-convex and concave surfaces.The tool path designed by this method has the advantages of smooth and uninterrupted,smooth cutting force and uniform surface residual,which can obtain high surface quality of parts.