Research On Grinding Process Of Leading And Trailing Edges Of Aero Engine Precision Forged Cold Rolled Blade

Blades are the key parts of aero-engine,its quality determine the working performance of the entire aero-engine.Because of the structure characteristics of blade is extremely complex,which belongs to the typical complex free-form surface and thin-walled parts.The blade is very difficult to process,dimensional accuracy and surface quality are not easy to guarantee because of these features.In recent years,more and more aero-engine blades are used precision forging cold-rolling method to process blade blank,the quality of blade surface can reach the required precision accuracy,and it does not need to be reprocessed,the edge of the blade is cut by a milling and then grinded by hand.Although this kind of method can avoid the processing of blade surface,not only the efficiency of this method is very low but also the mechanical working accuracy and the molding consistency of the edge of blade are pretty bad,it can affect the pneumatic working performance of the entire aero-engine.To solve the problems,this work conduct a series of research work as follows:The intelligent robot-belt grinding system is constructed,every parts of the system are given out and coordinate systems are built.The type and the parameters of robot are confirmed based on the theory of robot grinds blades.The grinding force is controlled by the abrasive belt grinding machine which grinding fore can be controlled.The theory of on-line detecting system is analyzed.The forward and inverse kinematics of robot was analyzed.The kinematics model of FANUC R-2000 i B was established by using the D-H method and the forward and inverse kinematics equations were obtained by using connecting rod matrix.The robot model was built and the theory of homogeneous transformation matrix and forward and inverse kinematics were simulated by using the toolbox functions of MATLAB robotics toolbox.The MATLAB program was programmed to show the simulation results directly in 3D space.The algorithm of generating grinding target points based on the model of the blade CAD was proposed.For the leading and trailing edges of elliptic arc,cross-sectional method and curvature difference method and the method of trajectory path are divided on curvature difference are adopted to calculate the row path and step path of the grinding trajectory.The control of the end effector attitude space of the robot was researched during the grinding process.According to the model reconstruction and model comparison,grinding allowance in the leading and trailing edges were determined,grinding force in different grinding points were determined.The self-adaption grinding of leading and trailing edges was achieved.Robot off-line programming techniques were studied.Path planning was based on the CAD model of blade in the off-line programming software named Roboguide,and robot grinding program was generated automatically based on off-line programming.The simulation of robot grinding blade was achieved,feasibility of this method was verified.