Single-stage vibratory gyroscope control methods for direct angle measurements

Abstract

This paper presents a control algorithm that can compensate for imperfect dynamics of vibrating gyroscopes. The compensated gyroscope dynamics can directly measure the rotation angle without integrating the angular rate. The direct angle measurement approach is promising because it is exempt from the error accumulation problem. However, using control methods to compensate for imperfect dynamics for the direct angle measurement is very challenging work, and very few control algorithms were reported to achieve that. Different from existing approaches, the proposed method has the following advantages: it requires the measurements of either the proof mass velocity or position, it does not require a calibration phase prior to normal use, and it compensates different types of imperfection even when the proof mass of a gyroscope is unknown. In a demonstration case, imperfections cause system parameters 20% deviated from their designated values; the measured signals are the proof mass velocities and contaminated by zero-mean white noise with a noise level of 0.1% full scale output (FSO); the angular rate to be measured is 200 sin(2 pi x 10t) deg s(-1). The proposed algorithm can compensate for those imperfections and achieve an angle measurement accuracy of 0.23 degrees.