Satoshi Tawara

Miniature tilting mechanism using piezoelectric actuators

A tilting mechanism using piezoelectric actuators which has two rotation degrees of freedom has been developed. The dimensions of the body of the tilting mechanism are 10 mm in diameter and 24 mm in length. We have achieved the following specifications of the tilting mechanism; +/- 20 degree(s) rotational angle in the orthogonal two axes, 30 seconds of the angular resolution, 10 degree(s)/sec of the maximum rotation speed, and 1.75 Nmm of the maximum torque. This paper describes the structure and the experimental results of the linear actuator and the tilting mechanism.

Novel fabrication method for 3D microstructures using surface-activated bonding and its application to micro-mechanical parts

The purpose of this work is to demonstrate that a novel fabrication method for 3-D microstructures (FORMULA) is applicable to fabrication of micro mechanical parts with a large flexibility. This method is a kind of layer manufacturing method of thin films for metallic or dielectric microstructures using surface-activated bonding (SAB). The bonding interfaces of thin films are investigated by transmission electron microscope (TEM). Voids were observed at the interfaces of both pure aluminum films and Al-Cu alloy films. The ratio of void on the Al-Cu/Al-Cu interface is much larger than that of Al/Al interface, although the films have the same surface roughness of 3nm in Ra (average roughness). And approximately 10nm-thick amorphous intermediate layers were found at the interfaces. Furthermore, we have fabricated a micro gear of 900μm in diameter and 200μm in height, which is about ten times as large as our previous test pieces. Overhung structures such as a bridge structure and a cantilever were also fabricated without supporting layers beneath them.