Optimal Synthesis Methods for MEMS pp 79-119 | Cite as

# Synthesis Methods for Electro-Thermal Actuation

## Synopsis

Electro-thermal actuation has a number of advantages in minute mechanical devices such as the ones found in Micro-Electro-Mechanical Systems (MEMS). In this chapter, we describe synthesis methods for a general class of electro-thermal-compliant (ETC) actuators and mechanisms. The ETC devices are similar to the widely used bimorph actuators, but to achieve differential thermal expansion they rely upon their particular shape of a single-material structure rather than mismatched thermal expansion coefficients of two or more materials. These are *smart by design* because their functionality does not depend on the “smartness” of materials. Determination of the shape of the elastic structure for a specified behavior constitutes the synthesis problem. The synthesis procedure incorporates accurate thermal modeling including convection, which is important at the micro scale due to the familiar scaling law of surface to volume ratio. Design concepts and algorithms, microfabrication procedures, and prototype devices are described in the chapter.

## Keywords

Design Variable Topology Optimization Line Element Synthesis Problem Elastic Analysis## Preview

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