In this paper the design of a micromachined disc is described. The disc is
encaged by electrodes at its top, bottom and periphery. Electrostatic forces
are used to levitate the disc at the centre position. Such a device has
applications for inertial sensors such as accelerometers and gyroscopes. It
has considerable advantages over existing approaches, including increased
independence of fabrication tolerances, online characteristics adjustment
and in particular, compared to vibratory rate gyroscopes, inherently rules out
quadrature error and the need for modal frequency tuning. A system level
model of such a device is presented and the fabrication process relying on
thick-film resist and electroplating is described.
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