Disturbance rejection in MEMS gyroscope: Problems and solutions

This paper presents a summary of the recent developments in practical applications of the active disturbance rejection control (ADRC) on MEMS gyroscopes. There are two major control problems associated with vibrational MEMS gyroscopes: to control two vibrating axes (or modes) of the gyroscope, and to estimate a time varying rotation rate. This paper demonstrates how the novel active disturbance rejection control approach solves these problems in the presence of the mismatch of natural frequencies between two axes, mechanical-thermal noises, Quadrature errors, and parameter variations. The scope of the ADRC applications on MEMS gyroscopes shown in this paper includes the continuous ADRC for the drive axis, the sense axis, two axes, and rotation rate estimation as well as the discrete ADRC implementation for the drive axis. The successful results demonstrate that the key problem in MEMS gyroscope is disturbance rejection and the most promising method is ADRC.