Development of an effective method to reduce mechanical coupling error in a micro quartz tuning fork gyroscope

Abstract

To overcome the performance limitations of quartz microelectromechanical system (QMEMS) gyroscopes, which are extensively employed in various applications, a method was developed in this study to effectively reduce the zero-output error, which is primarily caused by the anisotropy of the quartz crystal. The proposed method increases the gold counterweights at the end of the tuning fork beam and trims them to reduce the zero-output error. First, the vibrations were determined by conducting a theoretical analysis of ideal and non-ideal gyroscopes. A finite element analysis and simulation were then performed on gyroscope models with five structures, and the influences of different crystal edge positions and counterweight trimming methods on the vibrations and outputs of the gyroscopes were simulated. Thereafter, by analyzing the simulation and experimental results, we verified that the addition of counterweights and an error-eliminating method can reduce the zero-output error of QMEMS gyroscopes, and that specific alternative methods can achieve similar results.