Abstract: The detection capacitance analysis method based on substructure model for the tuning fork vibratory micro-mach- ined gyroscope fabricated by the bulk silicon micro-machining technology is put forward by employing the dynamic finite element theory of multi-degree of freedom, and the simulation of the micromachined gyroscope under working state is also realized to establish the mechanism model of fabrication defect to the performance of the micro-machined gyroscope with high precision and solve the problem of long computation time of optimization of micro-machined structure. The simulation is verified by experiments. From the analysis of the illustration, the important phenomena that the process variance and error of micro-machined gyroscope don’t influence the natural frequency much but influence final output characteristic of detectioncapacitance greatly is found. Based on promotion of analysis precision and efficiency, the analysis method and result have important reference value to the analysis and evaluation of robust performance of the tuning fork vibratory micro-machined gyroscope in coupled multiphysics fields environment.

Key words: Detection capacitance, Micromachined gyroscope, Process error, Substructure