Structural Design And Experimental Study Of Micro-feeding Tool Post Based On Topology Optimization

With the continuous development of science and technology,various high-precision and high-surface-quality parts are widely used in cutting-edge science and technology fields such as military defense industry,aerospace,molecular structure medicine and so on.Ultra-precision machining technicians are the key factors restricting the development of cutting-edge technology,and at the same time affect the improvement of a country's science and technology and comprehensive national strength.The traditional processing methods are difficult to meet the accuracy requirements for the processing of complex surface components such as complex optical curved surfaces and micro-structured functional surfaces.Fast tool servo technology has the advantages of high processing efficiency,high precision and good processing quality.It is one of the most promising machining technologies for high-quality and efficient machining of complex surface parts.Aiming at the problems of low positioning accuracy and rigidity in the fast tool servo system in China,this paper designs a new type of micro-feed tool post.The specific research content is as follows:Comprehensively analyze the research status and structural characteristics of micro-feed tool post at home and abroad,understand the relevant methods of structural optimization,use topology optimization method to optimize the flexible part of the micro-feed tool post,and based on the optimization results a new type of cross-plate flexible moving pair was obtained.The stiffness of the flexible moving pair is calculated and verified by finite element.The influence of the size and geometry of the flexible moving pair structure on its stiffness was analyzed.According to the design requirements of the micro-feed tool post and the basic principles and characteristics of the piezoelectric ceramic drive,a suitable piezoelectric ceramic driver and control power are selected.A new configuration of a micro-feeding tool holder driven by piezoelectric ceramics with a cross-plate flexible moving pair as the guiding mechanism was designed.Using the finite element method,the static and dynamic analysis of the entire micro-feed tool post were performed.The static analysis shows that the structural stiffness of the tool holder meets the design requirements,and the maximum stress of the tool holder is far less than the allowable stress of the material.The natural frequency of the tool post is determined by dynamic analysis.Using the processed micro-feed tool post,a test platform was built to test the maximum output displacement,positioning accuracy,resolution,and static stiffness and natural frequency of the tool post.The measured tool post stiffness was 15.53N/?m,resolution was12 nm,positioning accuracy was 6.8nm,natural frequency was 2336 Hz,and the corresponding step time was 17 ms.By comparing the analysis of the rigidity of the movingpair,the simulation of the overall structure of the tool holder and the test results of the basic characteristics,the rationality and reliability of the new micro-feed tool holder structure designed in this paper are verified.Provide technical support for precision and ultra-precision machining.