Design of a Compliant Vertical Micropositioning Stage Based on Lamina Emergent Mechanisms

Abstract

This article presents the design and development of a novel compliant vertical micropositioning stage (VMS) with a millimeter stroke and compact profile. The concept design of the stage is inspired by lamina emergent mechanisms. The overall mechanism is fabricated using a plate-like material, which can realize an out-of-plane motion vertical to the mechanism plane. The proposed architectural design guarantees the advantages of the center platform in terms of millimeter stroke, high compactness, and low displacement coupling ratio. Analytical models of the stiffness and resonant frequency of the stage are established by resorting to pseudorigid-body model and Lagrangian equations. They are validated by conducting simulation study with finite element analysis. For performance testing, a prototype stage driven by a voice coil motor is fabricated. Experimental results indicate that the stage (size: 100 mm × 100 mm × 5 mm) delivers a working stroke of 5.58 mm, displacement coupling ratio of 0.31%, and resolution of 0.71 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mu$</tex-math></inline-formula> m. It exhibits more geometric advantages over existing piezoelectric-actuated vertical stages. In addition, it has superior vertical compactness, linearity, and simplicity compared to a planar mechanism with vertical input and vertical output. The concept design proposed in this article provides a new solution for the design and development of compliant VMS.