A method of structural trimming to reduce mode coupling error for micro-gyroscopes

This paper presents a novel method of structural trimming to reduce the mode coupling error with the focus on micro-gyroscopes. A UV nanosecond laser was used to remove materials with determined size at certain point on the vibratory structure of the micro-gyroscope. The peak-peak voltage of the mode coupling error signal of the gyroscope prototype studied in this paper could be reduced from 3.52V to 0.082V. Furthermore, the zero-velocity output of the same gyroscope prototype was decreased from 244mV to 14mV after coarse trimming and fine trimming. Demonstrated theoretically and experimentally, this structural trimming by UV nanosecond laser is an effective way to reduce mode coupling error for improving the microgyroscope performance.