The Analysis of the Subharmonic Excitation in a Disk MEMS Gyroscope

In order to evaluate the impact of high frequency excitation signals, especially frequency-doubled signals, on the gyroscope’s performance, an analysis of the subharmonic excitation in a disk MEMS gyroscope is presented in this paper. Due to the existence of the quadratic nonlinearity, when subharmonic (double frequency) excitation signals are applied on electrodes, the gyroscope’s response converts to a mixed signal of the fundamental frequency and the double frequency. Based on the multi-scale method, the response of the disk gyroscope with quadratic nonlinearity is analyzed and tested under the subharmonic excitation. Compared with the primary excitation, the subharmonic response proves to have an additional time-varying response in addition to a steady-state response, indicating that it is a combination of different signals and depends on the oscillation time. The evolution of the periodic solution is closely related to the strength of the subharmonic excitation signal, which also determines the final manifestation of the gyroscope’s response after a long time. The work presented in this paper could help to better understand the subharmonic response of the MEMS gyroscope and analyze the impact of the high frequency noise.