Research On High Quality Machining Methods For Complex Contour Curves

Complex profile parts are widely used in aerospace,ship and automobile manufacturing.With the increasing demand of complex contour curve parts in various application fields,the processing technology of complex contour curve parts is very important,especially the tool path path planning and real-time interpolation technology has become the research focus of complex contour curve parts processing.In this paper,tool path planning and real-time interpolation techniques for complex contour curve machining are systematically studied,and some key techniques of tool path planning and real-time interpolation for complex contour curve machining are deeply studied.Aiming at the local tool path smoothing of complex contour curves,a transition algorithm of tool point adjustment based on tolerance band constraint and tool path corner of C3 b-spline curves for 5 consecutive times is proposed.In the case of conforming to the tolerance band,the cutter point is adjusted in the error sensitive direction according to the transfer error,which can effectively reduce the small linear approximation error.The 5-times b-spline curve is used for corner transition to realize the smooth transition of tool path.The transition transition of tool path corner is divided into two types of transition transition and solved by different constraints,which improves the solution efficiency of transition transition spline curve.MATLAB simulation software is used to verify the effectiveness of the algorithm,which can greatly reduce the corner transition error caused by spline curve.For the global smoothing of tool paths of complex contour curves,a NURBS curve interpolation fitting method which satisfies the global tangential vector constraints isproposed.The tool path is segmented by interpolation,and the NURBS interpolation fitting is divided into three types according to the end points of each NURBS interpolation fitting segment after segmentation.The feature points are extracted from each interpolation segment,the global tangential vector constraint interpolation fitting method is adopted for the feature points,the NURBS curve satisfying the fitting accuracy is generated iteratively,and the MTALAB simulation software is used to verify the correctness of the global tangential vector interpolation fitting method,and the results show that the algorithm can effectively improve the fitting error of the interpolation for the same feature points.An improved 7-segment s-type acceleration and deceleration strategy is proposed.Parameter forecast correction method of NURBS curve is used to close the information acquired by interpolation,and satisfy the biggest bow high error,the method of the maximum processing speed and acceleration of interpolation speed,to calculate the shortest acceleration period of processing and the shortest path length S deceleration period of machining path length S,judge the machining path length between velocity sensitive and S + S reduced the size of the relationship between different types of s-shaped speed to complete the whole machining path planning strategy planning,validation of NURBS interpolation algorithm based on MATLAB,Experimental results show that the algorithm can improve the machining speed of NURBS curve under the condition of satisfying the machining error.