Automated Frequency and Quality Factor Mismatch Compensation Method for MEMS Rate Integrating Gyroscope

This paper reports an automated mismatch compensation method for a rate integrating gyroscope (RIG). The eigenmodes of an ideal degenerated resonator are clockwise (CW) and counterclockwise (CCW) modes, which are independent each other. However, the frequency and Q-factor mismatches of the resonator, which are generally unavoidable because of fabrication imperfectness, entangles these eigenmodes. This cross-coupling effect between CW and CCW modes deteriorate the linearity and causes the angle locking [1]. Thus, in this paper, a method to detects the cross-coupling terms (i.e. the frequency and Q mismatches) and tunes the driving signals to compensate these mismatches was proposed. The proposed method was experimentally confirmed using an electromagnetic ring resonator. The cross-coupling terms, which come from the frequency and Q-factor mismatches, were reduced to be 3 orders of magnitude by this method.