Research On Optimization And Linear Interpolation Of CL Data For Five-axis CNC Machining

Five-axis CNC machine tools are indispensable for advanced equipment in the aerospace,defense,and automotive industries.The high-precision,high-speed machining of five-axis CNC machine tools relies on complex surface tool path planning and interpolation algorithms.Aiming at the shortcomings of the existing five-axis CNC machine tool pose optimization and linear interpolation algorithm,a tool pose optimization algorithm based on the minimum tool axis vector generation plane is proposed,which effectively reduces the nonlinearity during 5-axis NC machining.The error and the number of interpolation points improve the machining accuracy and efficiency.A five-axis machine tool pose efficient and smooth linear interpolation algorithm is proposed.The nonlinear pre-interpolation and S-curve velocity planning algorithms are used to guarantee the nonlinearity.The error does not exceed the limit and the smooth changes of speed and acceleration help to reduce machine damage and improve interpolation accuracy and efficiency.The paper is divided into six chapters,the main contents are as follows:The first chapter summarizes the domestic and international research status of nonlinear error control in five-axis NC machining,free-form five-axis machining tool pose optimization,CNC machine tool free curve interpolation and other related technologies,and introduces the defects of existing algorithms.The research background and significance of this paper are expounded,and the organizational framework of this paper is introduced.The second chapter proposes a kinematics and nonlinear error analysis method for five-axis CNC machine tools.The concept of NC machining tool pose and kinematic chain is introduced.The general kinematics model of five-axis CNC machine tool is established,and the inverse kinematics formula is deduced.The concept of nonlinear error of five-axis CNC machine tool is introduced.On the basis of the analysis,a simplified calculation model of nonlinear error is established.The third chapter proposes a tool pose optimization algorithm based on the minimum tool axis vector generation plane.First,the improved particle swarm optimization algorithm is used to re-plan the tool axis vector and optimize the rotation angle of the two rotating axes at the adjacent two tool positions where the nonlinear error exceeds the allowable value.In order to maintain the cutting shape and accuracy of the workpiece,the new tool position is calculated according to the new tool axis vector to ensure that the tool contact does not change.Secondly,in order to avoid the number of iterations and speed up the efficiency of the algorithm,and to reduce the nonlinear error fluctuation caused by linear angle interpolation,the position of the interpolation point is dynamically planned according to the magnitude of the nonlinear error between the interpolation points.The fourth chapter proposes an efficient and smooth linear interpolation algorithm for the five-axis machine tool pose.The similarities and differences between linear interpolation and NURBS curve interpolation are analyzed,and the shortcomings of RTCP linear interpolation method are pointed out.Based on RTCP linear encryption,the limit feed rate calculation model under nonlinear error constraints is constructed,and the feed rate adaptive pre-interpolation method under nonlinear error-machine tool dynamics-connection speed constraint is established.Interpolation accuracy.The similarities and differences of various acceleration and deceleration interpolation algorithms are analyzed.Based on the S-curve acceleration deceleration control,the speed,acceleration and jerk are changed efficiently and smoothly,which helps to reduce the vibration and impact of the machine tool and improve the interpolation efficiency.The fifth chapter simulates the impeller blade machining on the HT-AC five-axis CNC machine tool,and verifies the effectiveness of the proposed algorithm.The sixth chapter summarizes the full text,points out the main achievements and innovations of the article,and looks forward to the follow-up research work.