Abstract: An inertial guidance accelerometer is formed as an integrated, monolithic, structure. Silicon micro-machining techniques are used to combine mechanical and electrical components of the device in a single crystal silicon wafer. The proof mass, flexible hinge, and resonator are formed by etching portions of a substrate, while the electrical circuits are monolithically integrated into the substrate using standard circuit integration techniques. The accelerometer includes a feedback control circuit for the resonator, as well as a digital-to-analog converter, for providing digital output signals indicative of the acceleration force applied to the device.

Abstract: A system for measuring the position of a vibrating object relative to a reference point, such as the block of a ring-laser gyroscope relative to its case, uses a continuous velocity sensor that is noisy and subject to drift and a precise position crossing detector. A mixer-filter combines the data from the two sensors so that the capability of the velocity sensor to provide a continuous reading of position is exploited to interpolate data between the instants that the position crossing detector indicates that the object position crosses through zero. The mixer-filter is implemented in the form of an extended Kalman filter which operates upon the inputs to provide an optimum estimate of the position of the vibrating object.