Design and Modeling of Micro-displacement Amplifying Mechanism Using Revolute Joints and Flexible Hinges

In this paper, a mechanism based on flexible hinges and semi-cylindrical revolute joints to amplify the displacement of stack-type piezoelectric ceramic actuator is designed, and dynamic characteristics of the structure are discussed. The mechanism incorporates two semi-cylindrical revolute joints and some flexible hinges. The models of stress and friction moment of semi-cylindrical revolute joint are presented. On the basis of analysis on maximum input displacement, elastic deformation, displacement loss of flexible hinges and the effect of revolute joint on loading, the displacement magnification mechanism is obtained. The finite element method is used for comparison with the mathematical model. The results of the finite element analysis and theoretic analysis are in good agreement, which indicate the analytical methods are correct.