Mechanical Coupling Error Suppression Technology for an Improved Decoupled Dual-Mass Micro-Gyroscope

Abstract

This paper presents technology for the suppression of the mechanical coupling errors for an improved decoupled dual-mass micro-gyroscope (DDMG). The improved micro-gyroscope structure decreases the moment arm of the drive decoupled torque, which benefits the suppression of the non-ideal decoupled error. Quadrature correction electrodes are added to eliminate the residual quadrature error. The structure principle and the quadrature error suppression means of the DDMG are described in detail. ANSYS software is used to simulate the micro-gyroscope structure to verify the mechanical coupling error suppression effect. Compared with the former structure, simulation results demonstrate that the rotational displacements of the sense frame in the improved structure are substantially suppressed in the drive mode. The improved DDMG structure chip is fabricated by the deep dry silicon on glass (DDSOG) process. The feedback control circuits with quadrature control loops are designed to suppress the residual mechanical coupling error. Finally, the system performance of the DDMG prototype is tested. Compared with the former DDMG, the quadrature error in the improved dual-mass micro-gyroscope is decreased 9.66-fold, and the offset error is decreased 6.36-fold. Compared with the open loop sense, the feedback control circuits with quadrature control loop decrease the bias drift by 20.59-fold and the scale factor non-linearity by 2.81-fold in the ±400°/s range.

Design, Analysis and Simulation of a MEMS-Based Gyroscope with Differential Tunneling Magnetoresistance Sensing Structure

“…Finally, the displacement response simulation is implemented to determine the mechanical sensitivity and linearity of the TFG. The input angular rate is tested from −100°/s to 100°/s, which corresponds to the Coriolis force ( F c ) from −0.1754 µN to 0.1754 µN [ 33 ]. where m s is the sense-mode effective mass; is the input angular velocity; and are the drive frequency and phase; and, A d is the amplitude of drive force that can be acquired from: where n is the number of drive comb; , h and d 0 denote the vacuum permittivity, comb thickness and comb gap respectively; and, V d and V a are the offset and amplitude of drive voltage illustrated in Figure 4 .…”

A Digital Mode-Matching Control System Based on Feedback Calibration for a MEMS Gyroscope

“…MEMS Gyroscope Design. Structural schematic of the dual-mass decoupled MEMS gyroscope is shown in Figure 1 [25]. The MEMS gyroscope structure consists of two identical substructures.…”

“…Journal of Sensors expounded in our previous work [25]. The FPGA chip is EP3C55F484I7 from the Altera Corporation and has 5 585 × 10 4 programmable logic units, 2 396 × 10 6 RAM bits, 156 multipliers, and 4 PLL.…”

Vibration-Induced Errors in MEMS Tuning Fork Gyroscopes with Imbalance

“…Each gyro contains two modes vertical to each other (i.e., drive mode and sense mode). TFGs are divided into four groups by coupling each gyro’s two mode masses; that is, (1) CP type—TFGs that have coupled sense and drive masses on each gyro [ 17 ], (2) DS type—TFGs that have decoupled sense and drive masses with an anchored sense mass on each gyro [ 10 ], (3) DD type—TFGs that have decoupled sense and drive masses with an anchored drive mass on each gyro [ 18 , 21 ], (4) fully decoupled type—TFGs that have fully decoupled sense and drive masses with drive and sense masses anchored on each gyro [ 22 , 23 ]. They respond differently to external vibration for several reasons, as discussed in a previous study [ 19 ].…”