Precision Micro-displacement Worktable Vertical Scanning White Light Interferometer

With the development of the times, the requirement of accuracy in precision machinery manufacturing, precision measuring instruments and precise micro-displacement is getting higher and higher. Therefore, the precision positioning technology plays an important role in the precision manufacturing industry. But, as only the precision positioning technology progressing, the precision field will be developed. Especially, the precision positioning technology becomes more and more important in some high-tech research fields. As contains a micro-displacement worktable which provide nano-scale resolution ratio of stepping displacement, the precision positioning technology plays an important position in various areas of technology. Therefore, the micro-displacement worktable is researched when the precision positioning technology is studied. Thus, according to the actual need, the micro displacement worktable which is studied and used in the white interferometer.In this paper, the main contents are shows as follows:First, the major countries in the world are research in micro-displacement worktable in summery. And some achievements and development are gained in the precision positioning technology and micro-displacement worktable in our country.Then, the micro-displacement worktable, which is based on the requirement of verticality and precision and also used in the white interferometer, is designed. The piezoelectric ceramic and flexure hinge, which are the important components of the micro displacement worktable, are researched. But, there is inherent nonlinearity in the piezoelectric ceramic will influence in the application of the piezoelectric ceramics. So, the reasons of nonlinearity verified by experiment in piezoelectric ceramics are analyzed. To improve the performance of micro-displacement table, the key components of its arc-shaped flexure hinge, which contains: the radius, the minimum thickness of the hinge, connecting rod length and other parameters that impact on the rotational stiffness of flexure hinges, elastic resilience, maximum stress and so on, are studied. Other, based on a commonly used pairs of flexure parallel four-link structure and the finite element Ansys11.0 as a research platform, the various parameters of flexure hinges impact on performance of flexure hinge are analyzed. Also, the relevant parameters of flexure hinge are optimized by the genetic algorithm.Then, the stability of piezoelectric driven power which is influences on the displacement precision is the power source of piezoelectric ceramic actuator. So, it is important to design a fine performance piezoelectric ceramic drive power for the micro displacement worktable. According to the requirements of piezoelectric ceramic for piezoelectric ceramic drive power and influence factors of piezoelectric ceramic displacement, a ripple smaller piezoelectric ceramic power is designed.Finally, the micro displacement worktable is used in the white interferometer and measurement the surface morphology. So, the influence of the micro displacement worktable by drive power supply ripple signal is analyzed by using repeatability precision. Thus, it's known that accuracy precision between the micro displacement worktable and the white interferometer...