Analysis on the Errors Caused by the Axial Acceleration of a Single Mass Capacitive Vibratory Micro-machined Gyro and Design of High-order Low-pass Filtering Module

In order to estimate and get the flight attitude, trajectory, launching speed, ejection altitude, landing point, landing speed and displacement, etc. of aircraft, parameters of six degree of freedom inertial measurement unit are usually acquired to establish the settlement data base in the design and study of aircraft. Moreover, the gyro used to measure the angular rate is an important part of the six degree of freedom inertial measurement unit. Belonging to the category of dynamic measurement, the research in this paper, taking a single mass capacitive vibratory micro-machined gyro as the object and combining Coriolis principle with the measurement mechanism of capacitive micro-machined vibrating gyro, made an analysis on the measurement errors of angular rate of this kind of gyro caused by the axial acceleration. Meanwhile, a kind of anti-aliasing filtering module of signal preconditioning circuit of the gyro was designed in this paper by taking advantage of elliptic high-order low-pass filter, which was consonant with the frequency band range in the actual application of angular rate, and preferably restrained the errors caused by the axial acceleration of a single mass capacitive vibrating micro-machined gyro, and provided some important test data and recommendations for its engineering practice as well. Copyright © 2014 IFSA Publishing, S. L.