Study On The Influence Of Spline Interpolation On The Profile Accuracy Of Five Axis Forming Parts

With the continuous development of modern science and technology,various types of parts and new products are constantly emerging.The shape of the parts to be processed is becoming more and more complicated,and the processing capacity of multi-axis machine tools is also proposed.High demands.For the traditional linear interpolation method,there are the following problems: 1.The machining accuracy at the corners of complex curves is low 2.The acceleration changes repeatedly during the interpolation at the corners,resulting in larger machining errors and lower machining efficiency.In response to the above problems,this paper uses a five-axis CNC machine tool,based on post-processing,using a common language JAVA and Eclipse development platform,carried out a large corner local NURBS fitting technology research.The main research contents and work results are as follows:(1)First,the structural classification of five-axis machine tools is described.On the basis of the five-axis linkage CNC machine tool's own structural motion chain,the machine tool motion coordinate system is established,and then the relationship between the five-axis linkage CNC machine tool motion chain is analyzed to obtain the machine tool's The rotation angle calculation formula and coordinate transformation formula finally solve the kinematics of each axis of the machine tool,which provides the basis for the development of the post processor.(2)Starting from the theoretical basis of the NURBS curve,the mathematical basis of the NURBS curve is introduced,and the calculation method of the node vector of the NURBS spline curve is introduced.For the problem of the calculation of the base function of the NURBS spline curve is more cumbersome,a basis is introduced.The fast calculation method of the function introduces the fitting method of the NURBS curve,and then proposes the fitting method of the NURBS at the corner of the large curvature.After obtaining the G code through the CAM software,the analysis is performed to obtain the initial data points and eliminate the noise in the data points In view of the lack of the current five-axis NURBS spline processing code format,on the basis of the three-axis NURBS interpolation,by adding the orientation spline information,a five-axis NURBS interpolation code is proposed.(3)Using JAVA language,based on the Eclipse platform,developed NURBS fitting post-processing software at the corners of large curvature,using the software to generate three-axis code and five-axis code,for the three-axis code,use VERICUT software Perform simulation analysis.For the five-axis code,MATLAB software was used to simulate and analyze the code.