TWO AXIS NAVIGATION GRADE MICROMACHINED ROTATION SENSOR SYSTEM

摘要

A two axis closed loop angular rate sensor which provides a digital delta theta output signal. A drive member is formed of a single, silicon wafer having a pair of oppositely-facing planar surfaces. The drive member includes a frame and a drive member central portion connected to the frame and arranged to have rotational compliance between the frame and the central portion about an axis perpendicular to the planar surfaces o f the silicon wafer. Drive signals are applied to a plurality of electrodes on the central portion to cause rotational oscillation of the drive member central portion about a drive axis perpendicular to the planar surfaces of t he silicon wafer. A silicon sensing member is connected to the drive member. The sensing member has a central support member connected to the drive member central portion such that rotational oscillations of the drive member central portion are transmitted to the sensing member central portion. A sensing portion is connected to the sensing member central support member to allow the sensing portion to oscillate about the drive axis and to allow an input rotation rate about an axis perpendicular to the drive axis to produce out-of-plane oscillations of the sensing portions. Signal processing apparatus is connected to the sensing portion for producing a signal indicative of the input rotational rate as a function of the amplitude of th e out-of-plane oscillations of the sensing portion.