Page 106 - Mechanical design of microresonators _ modeling and applications

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Source: Mechanical Design of Microresonators

Chapter
3

Microhinges and

Microcantilevers: Lumped-

Parameter Modeling and Design

3.1 Introduction

This chapter focuses on microhinges and microcantilevers, specifically
on determining their lumped-parameter stiffness and inertia properties
to enable calculation of the corresponding resonant frequencies. The
material presented here builds upon the developments of Chap. 2 as
complex-shaped microhinges and microcantilevers can be fabricated by
combining the basic shapes introduced in Chap. 2.
Microhinges are elastic regions of monolithically built MEMS that
connect rigid parts and enable relative motions between these parts by
either bending or torsion elastic deformation. A microhinge, which is
connected to the substrate (ground) at one end and to a rigid body
(mass) at the other end, is illustrated in Fig. 3.1.
From a modeling viewpoint, hinges in the lumped-parameter domain
are considered as fixed-free members. Hinges in monolithic architec-
tures have been proposed for macro-scale applications in various
1
configurations such as right circular (Paros and Weisbord ) elliptical
3
2
(Smith et al. ), or corner-filleted (Lobontiu et al. ). Other configurations
including parabolic and hyperbolic, with two or multiple sensitive axes,
4
have been studied by Lobontiu from a compliance standpoint, whereas
5
Lobontiu and Garcia more recently provided the main elastic prop-
erties of a few hinge designs that can be implemented in MEMS
applications.

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