Projeto de atuadores piezelétricos flextensionais usando o método de otimização topológica. / Design of flextensional piezoelectric actuator using the topology optimization method.

AUTOR(ES)

Ronny Calixto Carbonari

DATA DE PUBLICAÇÃO

2003

RESUMO

Flextensional Piezoelectric Actuators consist of a flexible structure actuated by piezoelectric ceramics (or a stack of piezoceramics). The flexible structure connected to the piezoceramic must generate displacements and forces in different specified points of the domain, according to a specific direction. These actuators are applied to precision mechanic applications such as microelectromechanical systems (MEMS), cell manipulators, laser interferometers, nanotechnology equipment, microsurgery equipment, nanopositioners, scanning probe microscopy, etc. However, due to the fact these actuators essentially consist of a compliant mechanism their design is complex. The compliant structure behaves as a mechanical transform by amplifying and changing the direction of small output displacements generated by piezoceramics (order of nanometer). The flexible structure is designed by distributing flexibility and stiffness in the design domain, which can be archieved by using topology optimization. Therefore, the objective of this work is to implement a systematic method based on topology optimization method to design flextensional piezoelectric actuators. Essentially, the topology optimization method consists of finding the optimal material distribution in a perforated design domain with infinite microvoids. The material in each point can change from void to full material, also assuming intermediate (or composite) material. The implemented topology optimization method is based on the SIMP (Simple Isotropic Material with Penalization) material model. The optimization problem is posed as maximization of output displacements (or grabbing forces) in different specified directions and points of the domain. A linear behavior of piezoceramic is considered. By changing the flexibility and stiffness of flexible structure connected to the piezoceramics different types of flextensional piezoelectric actuators can be designed for a desired application. To illustrate the method, examples presented herein are limited to two-dimensional (2D) models once in most part of applications of these actuators they are planar devices. These actuators are manufactured by using chemical corrosion on a 200 um thickness copper plate through lithography method. Chemical corrosion technique has a low cost and it allow us to manufacture several prototypes for testing. For this technique, facilities of the micromachining laboratory of National Sincroton Light Laboratory (LNLS - Campinas) are used. Experimental analysis of these prototypes are conducted by measuring displacements using a probe station. As a future work, these prototypes will be built in a MEMS scale.

ASSUNTO(S)

nanoposicionadores topology optimization nanopositioners otimização topológica flextensional piezoelectric actuators mems mems atuadores piezelétricos

Documentos Relacionados

• Design of multi-phase micromechanisms using the topology optimization method.
• Projeto de transdutores baseados em placas piezelétricas através do método de otimização topológica.
• Projeto de dispositivos de microcanais utilizando o método de otimização topológica.
• Método de otimização topológica aplicado ao projeto de sonotrodos para transdutores piezelétricos.
• Manufacturing constraints applied to the topology optimization method.