Research On A 3 DOF Planar Micro-Motion Stage Based On Parallel Mechanism

The goal of the research described in this thesis is to develop a parallel planar micro-motion stage. This micro-motion stage is constructed based on the compliant mechanism concept. It's a monolithic compliant mechanism utilizing flexure hinges. The micro-motion stage is actuated by three PZT stack actuators. It is designed based on the 3RRR mechanism. The structure of this stage is symmetrical to the center and the end-effector platform of the stage can translate along x, y-axis and rotate about the z-axis.In this thesis, inverse and direct position analysis of the RRR micro-motion stage is derived based on the constraint conditions of parallel manipulator and a constant-Jacobian method for kinematic analysis of the RRR micro-motion stage is developed. This thesis also presents a method of deriving a simple, linear and yet effective kinematic model based on the loop closure theory and the concept of the pseudo-rigid-body model. The static model of the micro-motion stage is also presented, and the relationship between the vector of end-effector output force or moment and the vector of actuated joint torques or force is derived. The dynamic model is derived using the Lagrangian equation.Finally, the experiment of the micro-motion stage kinematic capability is studied. The data of experiment is compared with the results of the finite element analysis and constant-Jacobian method, and it is confirmed that the constant -Jacobian method is an effective and correct method for kinematic analysis.