Finite Element Method Analysis of Single Crystal Tuning Fork Gyroscope for Suppression of its Inner Leakage Coupling

To suppress the null signals in a LiTaO3 crystal fork gyroscope, we analyzed the fork's vibration modes using the finite element method (FEM) and proposed adding a slit to the base of the fork. In the base with a slit, the movement of the fx mode is very low level but the symmetrical motion is the same as of the arm for the fz mode. Therefore, we can place a detecting electrode where the driving mode is negligible. Since the slit also improves the mechanical balance for the fz mode and suppresses a precessional motion, the mechanical coupling decreases to less than 1/10.