Application of nonlinear driving in frequency matching of tunneling gyroscope

摘要

The nonlinear vibration behavior of driving mode of a tunneling gyroscope is measured and simulated. Based upon these testing results, a new method for frequency matching is presented. Compared to traditional harmonic vibration, large amplitude and wide shift resonance frequency could be obtained in stable region of nonlinearity by using this approach, especially, in this region gyroscope could spontaneously vibrate at a certain driven frequency without needing sweep-up frequency excitation. In our tunneling gyroscope, the vibration amplitude changes from 1µm to 5µm at jumping-up point J′ with the amplitude of the excitation electrostatic force increasing. At the same time, the resonant frequency of driving mode can be shifted from nature frequency 1.81 kHz to 2.2 kHz, which is much closed to the resonant frequency of sensing mode (2.23 kHz). This effect can be used as an alternative approach to trim the frequency and eliminate the frequency mismatching for the post-fabrication tunneling gyroscope, eventually, higher sensitivity could be gotten than using linear driving mode.