Effective bias warm-up time reduction for MEMS gyroscopes based on active suppression of the coupling stiffness
Effective bias warm-up time reduction for MEMS gyroscopes based on active suppression of the coupling stiffness
复制标题
基于耦合刚度的主动抑制，有效缩短 MEMS 陀螺仪的偏置预热时间
DOI：
10.1038/s41378-019-0057-2
复制
发表时间：
2019-05-06
影响因子：
7.9
通讯作者：
Yan, Guizhen
中科院分区：
文献类型：
--
作者：
Cui, Jian;Zhao, Qiancheng;Yan, Guizhen
偏置预热时间是MEMS陀螺仪在打开电源后达到具有规定性能的相对稳定状态所需的时间，是短飞行时间导航应用的关键因素。本文提出了一种基于主动抑制耦合刚度（ASCS）的开环读出方案，有效提高了分离式MEMS陀螺仪偏置预热时间的方法。建立了影响偏置预热时间的主模谐振频率、主模与感模之间的频率差、耦合刚度以及解调相位误差的偏置温度灵敏度的半定量数学模型。在所有参数中，刚度耦合变化对启动预热时间的影响最大，其次是相位误差漂移。实验结果表明，通过对耦合刚度的闭环控制，在1小时的测试时间内，当偏置稳定性（1σ）降至10°/h左右时，偏置预热时间从2000 s减少到2 s，降低了3个数量级。此外，采用ASCS后，陀螺仪的偏置不稳定性从4°/h提高到2°/h，提高了2倍。
Bias warm-up time is the time required for MEMS gyroscopes to reach a relatively stable state with specified performance after the power supply is turned on, is a critical factor for short time-of-flight navigation applications. This paper demonstrates an effective method to improve the bias warm-up time of a custom-designed MEMS gyroscope operating in split-mode based on open-loop readout scheme with active suppression of the coupling stiffness (ASCS). A semi-quantitative mathematical model for the temperature sensitivity of the bias is established that indicates the resonant frequency of the primary mode, the frequency difference and the coupling stiffness between the primary and sense modes together with the demodulation phase error, and these are the main factors that affect bias warm-up time. Of all these parameters, the stiffness coupling variation contributes the most to the start-up warm-up time, followed by the phase error drift. The experimental result shows that the bias warm-up time decreases from 2000 to 2 s under the condition that the bias stability (1σ) falls into about 10 deg/h within an hour of testing time using closed-loop control for the coupling stiffness, resulting in a reduction of three orders of magnitude. In addition, the bias instability of the gyroscope is improved two-fold from 4 to 2 deg/h with ASCS.