Performance Analysis of a CSFH-Based Microgripper: Analytical Modeling and Simulation

Abstract

Microgrippers are promising tools for micro-manipulation and characterization of cells. In this paper, a biocompatible electro-thermally actuated microgripper with rotary capacitive position sensor is presented. To overcome the limited displacement possibilities usually provided by electrothermal actuators and to achieve the desired tweezers output displacement, conjugate surface flexure hinges (CSFH) are adopted. The microgripper herein reported can in principle manipulate biological samples in the size range between 15 and 120 µm. A kinematics modeling approach based on the pseudo-rigid-body-method (PRBM) is applied to describe the microgripper’s working mechanism, and analytical modeling, based on finite elements method (FEM), is used to optimize the electrothermal actuator design and the heat dissipation mechanism. Finally, FEM-based simulations are carried out to verify the microgripper, the electrothermal actuator and heat dissipation mechanism performance, and to assess the validity of the analytical modeling.

A C-shaped hinge for displacement magnification in MEMS rotational structures

“…The CSFH provides several benefits, including the reduction of internal stress, its durability during operation, and the optimization of the overall relative hinge rotations. These hinges are implemented to construct planar, compliant, and monolithic microgrippers, supporting rotational motion, for cell and tissue manipulations 12 – 14 .…”