Zhiwei Kou

Prof. Dr. Zhiwei Kou


Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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13 March 2019 in Micromachines
Verified
Journal Article
Open access
PDF file
Huiliang CaoHuiliang Cao
Huiliang Cao
YLYu Liu
Yu Liu
ZKZhiwei Kou
Zhiwei Kou
YZYingjie Zhang
Yingjie Zhang
XSXingling Shao
Xingling Shao
JLJun Liu
Jun Liu
This study presents a new microelectromechanical system, a vibration ring gyroscope with a double U-beam (DUVRG), which was designed using a combination of mathematical analysis and the finite element method. First, a ring vibration resonator with eight double U-beam structures was developed, and 24 capacitive electrodes were designed for drive and sense according to the advantageous characteristics of a thin-shell vibrating gyroscope. Then, based on the elastic mechanics and thin-shell theory, a mathematical stiffness model of the double U-beam was established. The maximum mode resonant frequency error calculated by the DUVRG stiffness model, finite element analysis (FEA) and experiments was 0.04%. DUVRG structures were manufactured by an efficient fabrication process using silicon-on-glass (SOG) and deep reactive ion etching (DRIE), and the FEA value and theoretical calculation had differences of 5.33% and 5.36% with the measured resonant frequency value, respectively. Finally, the static and dynamic performance of the fabricated DUVRG was tested, and the bias instability and angular random walk were less than 8.86 (°)/h and 0.776 (°)/√h, respectively.

7 January 2016 in Sensors
Verified
Journal Article
Open access
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Huiliang CaoHuiliang Cao
Huiliang Cao
HLHongsheng LI
Hongsheng LI
ZKZhiwei Kou
Zhiwei Kou
YSYunbo Shi
Yunbo Shi
JTJun Tang
Jun Tang
JLJun Liu
Jun Liu
This paper focuses on an optimal quadrature error correction method for the dual-mass MEMS gyroscope, in order to reduce the long term bias drift. It is known that the coupling stiffness and demodulation error are important elements causing bias drift. The coupling stiffness in dual-mass structures is analyzed. The experiment proves that the left and right masses’ quadrature errors are different, and the quadrature correction system should be arranged independently. The process leading to quadrature error is proposed, and the Charge Injecting Correction (CIC), Quadrature Force Correction (QFC) and Coupling Stiffness Correction (CSC) methods are introduced. The correction objects of these three methods are the quadrature error signal, force and the coupling stiffness, respectively. The three methods are investigated through control theory analysis, model simulation and circuit experiments, and the results support the theoretical analysis. The bias stability results based on CIC, QFC and CSC are 48 °/h, 9.9 °/h and 3.7 °/h, respectively, and this value is 38 °/h before quadrature error correction. The CSC method is proved to be the better method for quadrature correction, and it improves the Angle Random Walking (ARW) value, increasing it from 0.66 °/√h to 0.21 °/√h. The CSC system general test results show that it works well across the full temperature range, and the bias stabilities of the six groups’ output data are 3.8 °/h, 3.6 °/h, 3.4 °/h, 3.1 °/h, 3.0 °/h and 4.2 °/h, respectively, which proves the system has excellent repeatability.

8 June 2016 in Sensors
Verified
Journal Article
Open access
PDF file
YSYunbo Shi
Yunbo Shi
ZYZhicai Yang
Zhicai Yang
ZMZongmin Ma
Zongmin Ma
Huiliang CaoHuiliang Cao
Huiliang Cao
ZKZhiwei Kou
Zhiwei Kou
JLJun Liu
Jun Liu
Despite its extreme significance, dynamic linearity measurement for high-g accelerometers has not been discussed experimentally in previous research. In this study, we developed a novel method using a dual-warhead Hopkinson bar to measure the dynamic linearity of a high-g acceleration sensor with a laser interference impact experiment. First, we theoretically determined that dynamic linearity is a performance indicator that can be used to assess the quality merits of high-g accelerometers and is the basis of the frequency response. We also found that the dynamic linearity of the dual-warhead Hopkinson bar without an accelerometer is 2.5% experimentally. Further, we verify that dynamic linearity of the accelerometer is 3.88% after calibrating the Hopkinson bar with the accelerometer. The results confirm the reliability and feasibility of measuring dynamic linearity for high-g accelerometers using this method.

26 November 2024 in Micromachines
Verified
Journal Article
Open access
PDF file
KCKe Cui
Ke Cui
LLLi Liu
Li Liu
DADaren An
Daren An
XWXinyu Wang
Xinyu Wang
QAQi An
Qi An
Huiliang CaoHuiliang Cao
Huiliang Cao
This paper proposes a method to control the sensitivity of a ring MEMS gyroscope by adjusting the driving control voltage via MEMS. The aim is to explore the relationship between the range of the ring MEMS gyroscope and the driving control voltage, establishing a mathematical model that correlates driving control voltage with sensitivity. By applying different driving voltages to the same gyroscope, the study evaluates the performance and range of the gyroscope. Experimental results demonstrate that lower driving voltages increase the gyroscope’s range. At a driving voltage of 10.85 V, the gyroscope achieves a range of ±200°/s, a minimum resolution of 0.019°/s, and a nonlinearity of 22.37 ppm. At 1.46 V, the gyroscope range expands to ±1000°/s, with a minimum resolution of 0.05138°/s and a nonlinearity of 60.73 ppm. As the measurement range increased fivefold, the degradation in gyroscope performance was significantly less than the scale of range expansion. Compared to the gain in modulation detection circuitry, gyroscope performance was optimized across the entire operational range.