| Ultra-precision manufacturing technology has been widely used in the area of aviation, aerospace, optical, precision machinery and so on,therefore, many countries pay great attention to it. At present, there is a big gap of technology and equipment between China and Europe, America, Japan and other developed countries. So most advanced equipments are needed to import. But it is very difficult to buy them from abroad. To solve this problem, it is an effective method that installs some devices on the machines to realize tool compensation. By analyzing and summarizing the current driven platform used for ultra-precision machining, a proposal is made that use the piezoelectric stack to drive to achieve compensation. And also, for some materials that can not cutting, another device is designed used for burnishing.Firstly,the theory of ultra-precision cutting technology is introduced, the cutting depth is closely related to the tool angle. The characteristics of diamond tool are introduced. It also introduces several factors of ultra-precision cutting: the accuracy of machine, environment. The burnishing theory is analyzed, and the relationship between burnishing plastic deformation and pressure is got. The driving theory and the characteristics of piezoelectric are introduced, including mechanical features, response characteristics, hysteresis, creep characteristics, resolution and repeatability.Then, the flexible hinge is introduced in details, the advantages and disadvantages of structure and material of the flexible hinge is evaluated. The stiffness of the flexible hinge is calculated. And then, the flexible hinge is analyzed by using FE. In theory the strength and stiffness of the flexible hinge can meet the requirement. The piezoelectric stack is used as power source, displacement is output by flexible hinge, and detected by sensor, then the data is passed to the controller, the devices are constitute a closed-loop. The preload of drive platform is analyzed, and the mechanical model is established, finally get the transfer function. The finite element model analysis is carried out to predict the performance and frequency of the device.Product the drive platform, and build the test system to test the stability and output capacity. Install the device on the ultra-precision lathe to cutting, achieve good results by cutting different materials. By comparing with the CNC diamond tool, it proves that the performance of the lathe has improved. Finally, by changing the cutting parameters, get the optimal cutting parameter is v = 100m/min, a p= 1μm, f = 1μm/r.Proposed the idea of the device that used for burnishing . Introduce the theory and work process, analyze the promoter structure. The simulation of the burnishing is carried out by using the finite element contact mechanics analysis. Product the burnishing tool, and test the vacant load capacity and do the burnishing experiments. The burnished surface has obviously changed after burnishing. The burnishing experiments show that the burnishing times on the hardness results are consistent with the Marc analysis. At last test the device by changing the depth, feed and speed respectively.Finally, make a conclusion to the article, analyze the problem that meet in the design and experiment process, give some suggestion for future. This research is funded by the International Scientific and Technological Cooperation Project (Grant No.2010DFA7200), Doctoral Program of Higher Education of China (200801831024).
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