Study On Vibration And Surface Topography In Robotic Forward And Backward Fine Boring Of Aircraft Intersection Holes

As an important part of aircraft assembly technology——the finish of aircraft intersection holes’ machining quality and pose accuracy of intersection holes directly affect assembly quality and interchangeability of aircraft components.,it is of great significance to improve the service life of aircraft and ensure the safe flight.There are many shortcomings in fine boring of intersection holes with traditional large numerical control machine and manual work,it is unable to meet the requirements of aircraft digital assembly.Therefore,in this paper,a robotic fine boring system with industrial robots and end-effector is adopted to finish the machining of aircraft intersection holes.In the preliminary study of the project,it has been discovered that vibration is very easy to occur due to the weak rigidity of the robot in the process of machining.Once the vibration occurs,it will seriously affect the workpiece processing quality and tool life,and reduce the processing efficiency.In this paper,the vibration and surface topography in robotic forward and backward boring are studied.Firstly,it elaborates the research background and significance,and the research status of cutting vibration and surface topography is analyzed and summarized.The components and characteristics of robotic fine boring system are introduced in detail,according to the machining requirement of the aircraft intersection holes,the specific process is formulated.Base on the B&K modal analysis platform,modal analysis experiments of the system are carried out by using the moving force hammer method,and the modal parameters of the system are obtained.The dynamic model of the robot fine boring system is established,and the influence of forward and backward boring on the system is analyzed.It is found that the opposite direction of the axial component of the cutting force in the forward and backward boring will affect the friction force of the pressure foot.Based on this,a backward boring method is proposed to suppress or reduce vibration,and the correctness of the model is verified by boring test.The traditional methods of vibration signal feature analysis and the principle of fusion analysis are summarized.Based on the Hilbert-Huang transform for typical chatter signals,the FastIC A algorithm based on the principle of feature level fusion for feature fusion analysis has been adopted,it can make the identification and prediction of chatter in machining process more reasonably and efficiently,and reduces the risk of misstatement and missing report.Analysis of the surface topography of parts and its influencing factors,and combines the vibration between the tool and the workpiece,a tool path model for boring is established.With the help of MATLAB,the simulation analysis of three-dimensional surface topography of boring hole is carried out for five main influencing factors.The correctness of the model is verified by tests,which provides a new way to optimize the parameters and improve the machining quality.Finally,the work done in this paper is summarized,and the prospect of further research is put forward.