The constant‐Jacobian method for kinematics of a three‐DOF planar micro‐motion stage

This paper concerns the development of a class of devices that generate end‐effector motion in the range of less than 100 μm and with sub‐nanometer resolution; in particular, a parallel manipulator configuration that generates a planar x‐y‐γ motion is considered. The parallel manipulator is implemented as a compliant mechanism. A problem with parallel manipulators is that the forward kinematics is usually too complex, which can hinder the implementation of advanced control algorithms. The contribution of this paper is that a simple method, called the constant‐Jacobian (CJ) method, is developed based on the pseudo‐rigid body (PRB) approach to compliant mechanisms. The experiment validates the CJ method.