Y. Ikei et al., DEVELOPMENT OF A FLUID-DRIVEN MICROACTUATOR, JSME international journal. Series C, dynamics, control, robotics, design and manufacturing, 40(1), 1997, pp. 97-103
In this paper we describe a new design of a fluid-driven microactuator
which comprises a planar piston, a four-way control valve, and a mech
anical feedback system that controls the output in accordance with an
input displacement. Merits of this design are expected in terms of out
put density, scalability, and feedback ability realized with no electr
onic devices. Fabrication processes of the microactuator include bulk
micromachining of two sheets of silicon substrate and their assembly b
y electrostatic bonding to glass plates. The output characteristics we
re measured while compressed air was supplied. Generated output force
showed an almost linear relationship to supplied pressure and to valve
displacement. However, the magnitude was asymmetric in terms of drive
n directions, which resulted from geometrical configuration essentiall
y introduced by an anisotropic etching of the silicon substrate. The p
osition of the output shaft was sufficiently controlled with a designe
d magnification factor multiplied to the input displacement in both st
atic and dynamic senses.