A smart material microamplification mechanism fabricated using LIGA

Abstract

A unique microamplification mechanism formed through the merging of smart material and microelectromechanical system concepts is presented. This microamplification device increases the useful actuation stroke of piezoceramic material through the amplification of piezoceramic strain. The technology demonstrated has utility as a microactuation mechanism for driving micropiezomotors, hearing aid transducers and precision optical switches. The microamplifier, approximately 2000 µm × 200 µm × 800 µm, is composed of electroplated nickel and was constructed using LIGA. An overview of microactuator system requirements and the advantages of scaling the flexure based amplifier illustrates the utility of the new device. The microamplifier is a radically scaled version of a mesoscopic mechanism. An analytical discussion of the operation is presented along with a finite-element analysis of the static and dynamic properties of the microlever. The analytical study is used to develop the operation principles and expected performance of the microamplifier. Experimental static and dynamic testing results are presented that confirm the analytical study. The mechanism has a mean amplification ratio of 5.48, an elastic stroke range of 8 µm and a fundamental frequency of 82 kHz.

Analysis of the displacement amplification ratio of bridge-type mechanism

“…Pokines and Garcia [21] derived the ideal displacement amplification ratio of bridge-type mechanism from the angular variation of bridge arm:…”

“…Pokines and Garcia [21] analyzed the relationship between the ideal displacement amplification ratio of bridge-type mechanism and the angular variation of bridge arm, as he designed and fabricated a MEMS-type micro-amplification device. Lobontiu and Garcia [22] analyzed the relationship between the ideal displacement amplification ratio of bridge-type mechanism and input displacement.…”

Design and optimization of a XY compliant mechanical displacement amplifier

“…Numerous literatures regarding this topic can be found in Ananthasuresh and Saxena (2000); Bharti and Frecker (2004);Furukawa et al (1995); Kota et al (1999); Pokines and Garcia (1998);Tian et al (2009);Yang et al (1996). In general, the performance of a CMDA is a function of some important parameters such as the material properties and the flexure hinge profile of the mechanical displacement amplifier.…”

Micro-scale force-fit insertion

“…Potential military applications exist in safety and arming systems 8 . Broad applications exist for a range of gears, sensors, inductors, actuators, transducers, chemical detectors, and micro-amplification structures 9,10,11 .…”