A novel positioning stage with resolution enhancement functionality for nano manipulation

With the rapid development of nano science and precision engineering, a positioning system with high resolution is indispensable to meet the requirement of precise positioning. This paper presents the design and modeling of a flexure-based positioning stage with the functionality of resolution enhancement. To achieve high enhancement ratio, two sets of displacement reduction mechanisms are incorporated and configured serially in a monolithic symmetrical design. Following the assumption that the flexure hinge can be equivalent to an ideal revolute joint with a torsional spring, theoretical models are established to analyze the resolution enhancement ratio and dynamic performance of the positioning stage. Moreover, finite element analysis (FEA) is conducted to study the performances of the mechanism and verify the theoretical models. The results show that the proposed mechanism can achieve a resolution enhancement ratio of 18.75 to improve the positioning performance, and the first order natural frequency of the mechanism is 535.5Hz, which guarantees the bandwidth of the positioning operation.