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Optically levitated micro gyroscopes with an MHz rotational vaterite rotor

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Microsystems & Nanoengineering 2024年第3期10卷 219-227页

作者： Kai Zeng Xiangming Xu Yulie wu xuezhong wu Dingbang Xiao College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China College of Information and Communication National University of Defense TechnologyWuhan 430000China Key Laboratory of Satellite Navigation Technology National University of Defense TechnologyChangsha 410073China

The field of levitated optomechanics has experienced significant advancements in manipulating the translational and rotational dynamics of optically levitated particles and exploring their sensing *** concept of using optically levitated particles as gyroscopes to measure angular motion has long been explored but has not yet been proven either theoretically or *** this study,we present the first rotor gyroscope based on optically levitated high-speed rotating *** gyroscope is composed of a micrometer-size ellipsoidal vaterite particle that is driven to rotate at MHz frequencies in a vacuum *** an external angular velocity is input,the optical axis deviates from its initial position,resulting in changes in the frequency and amplitude of the rotational *** analyzing these changes,the angular velocity of the input can be accurately detected,making it the smallest rotor gyroscope in the *** angular rate bias instability of the gyroscope is measured to be 0.08°/s and can be further improved to as low as 10^(−9)°/h theoretically by cooling the motion and increasing the angular moment of the levitated *** work opens a new application paradigm for levitated optomechanical systems and may pave the way for the development of quantum rotor gyroscopes.

关键词： particles rotational angular

Six million Q factor micro fused silica shell resonator with teeth-like tines released by femtosecond laser-assisted chemical etching

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Science China(Technological Sciences) 2024年第6期67卷 1923-1932页

作者： ZHAO Tao SHI Yan LU Kun XI Xiang wu xuezhong XIAO DingBang College of Intelligence Science and Engineering National University of Defense TechnologyChangsha410073China

The quality factor(Q factor)is a crucial performance parameter for *** this paper,a novel release method for highquality micro fused silica shell resonators with teeth-like tines with good surface morphology is *** method is based on femtosecond laser-assisted chemical ***,the optimal energy range of femtosecond laser modification is obtained through mechanism ***,the optimal parameters for a straight line and arc pattern are determined by optimizing the average output power,processing speed,and processing *** results demonstrate why edge breakage in rounded corners is easy under different ***,according to these conclusions,the processing is performed on a micro fused silica shell resonator with a Q factor exceeding 6 *** addition,subsurface damage is rare throughout the fabrication process,and the surface roughness of the released cross section reaches the nanometer *** improved Q factor helps suppress mechanical thermal noise and reduce zero bias and zero bias drift,constituting the primary method for enhancing the performance of the resonant gyroscope.

关键词： micro hemispherical resonator fused silica laser-assisted chemical etching quality factor

Design and Characterization of a Novel Z-axis Quartz Cross-fork Micromachined Gyroscope

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Chinese Journal of Mechanical Engineering 2011年第1期24卷 50-57页

作者： XIE Liqiang wu xuezhong LI Shengyi WANG Haoxu TAO Yi DONG Peitao College of Mechatronics Engineering andAutomation National University of Defense Technology Changsha 410073 China Engineering Institute of Engineering Corps PLA University of Science and Technology Nanjing 210007 China wuhan Ordnance N. C. O. Academy Wuhan 430075 China

The existing researches on quartz gyroscope mainly focus on the structure design of the tuning fork, which aim at obtaining a better vibration characterization. However, the fabrication of complicated structure is a challenge for present processes, and the imperfect fabrication process seriously affects the performances of the sensors. In this paper, a novel quartz cross-fork structure micromachined gyroscope is proposed. The sensor has a simple structure in x-y plane of quartz crystal. Unlike other quartz gyroscopes, the proposed gyroscope is based on shear stress detection to sense Coriolis’ force rather than normal stress detection. This feature can simplify the sensing electrode patterns and miniaturize the structure easily. Then the mechanical analysis of the structure is discussed. In order to obtain high sensitivities and uniform characteristics between different structures, the sensing beam is designed to be tapered, and the taper should be appreciably greater than 1°. This scheme is validated by finite element analysis software. The dynamic characteristic of the structure is analyzed by lumped parameter model. The dynamic stress in the beam and the detection sensitivity are deduced to optimize the structure parameter of gyroscope. Finally, the gyroscope is fabricated by quartz anisotropic wet etching. The prototype is characterized as follows. The drive mode frequency is 13.38 kHz, and the quality factor is about 900 in air. The scale factor is 1.45 mV/（（°） s –1 ） and the nonlinearity is 3.6% in the dynamic range of ±200°/s. Process and test results show that the proposed quartz gyroscope can achieve a high performance at atmosphere pressure. The research can simplify the fabrication of the quartz gyroscope, and is taken as a novel method for the design of quartz gyroscope.

关键词： quartz gyroscope cross-fork dynamic analysis Coriolis’ force

Precision Balance Method for Cupped Wave Gyro Based on Cup-bottom Trimming

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 63-70页

作者： TAO Yi XI Xiang XIAO Dingbang TAN Yingqi CUI Hongjuan wu xuezhong College of Mecha tronics Engineering and Automation National University of Defense TechnologyChangsha 410073China wuhan Ordnance N.C.O.Academy Wuhan 430075China Department of Mechatronics Engineering Zhuhai CollegeJilin UniversityZhuhai 519041China

The mechanical balance process is the key process to eliminate the quadrature error and improve the performance of the cupped wave gyro. The conventional mechanical balance method for cupped wave gyro based on cup-wall trimming requires high control accuracy of trimming quantity, which increases the production cost and decreases the fabrication efficiency in large extent. However, it is hard to reach the high balance accuracy with the natural frequency split of mHz grade by using the conventional method. In this paper, the lumped mass dynamic model of the cupped wave gyro is built by discretization method, and the effects of different position trimming on the natural frequency are analyzed. It is pointed out that trimming off a tiny quantity of material from cup-wall causes large variation of the natural frequency is the main reason for the low accuracy of the conventional mechanical balance method. Then, a precision balance method for cupped wave gyro based on cup-bottom trimming is presented and the entire procedures of this method are given. The static balance process and dynamic balance process of the precision balance method are simulated by the finite element software. The simulation result shows that the precision balance method based on cup-bottom trimming brings less additional natural frequency split in the static balance process, minimizes the natural frequency split to mHz grade and rectify the angle of mode offset to 0.1° grade in the dynamic balance process, furthermore, the method decreases the requirement for control accuracy of trimming quantity evidently. The research work provides references for structure optimization design and balance process plan of the cupped wave gyro.

关键词： cupped wave gyro precision balance trimming modal analysis natural frequency split

Removal of the rate table:MEMS gyrocompass with virtual maytagging

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Microsystems & Nanoengineering 2023年第6期9卷 175-184页

作者： Tongqiao Miao Qingsong Li Liangqian Chen Junjian Li Xiaoping Hu xuezhong wu Wenqi wu Dingbang Xiao College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China

High-performance micro-electro-mechanical system(MEMS)gyrocompasses for north-finding systems have been very popular for *** this paper,a MEMS north-finding system(NFS)based on virtual maytagging(VM)is presented for the first *** stark contrast to previous schemes of MEMS-based NFSs(e.g.,carouseling,maytagging)and the abandoning rate table,we developed a honeycomb disk resonator gyroscope(HDRG)and two commercial accelerometers for azimuth *** of the physical rotation of the integrated turntable in traditional NFSs,the vibratory working modes of the HDRG are rotated periodically with electronic control to reduce the uncertainty in the *** systematically analyzing the principle of NFSs with VM,we designed tests to verify the practicability at the sensor level.A bias instability of 0.0078°/h can be obtained during one day with VM in an *** also implemented comparative north-finding experiments to further check our strategy at the system *** accuracy in the azimuth can reach 0.204°for 5 min at 28.2°latitude with VM and 0.172°with *** results show that without any mechanical turning parts,VM technology makes it possible to develop high-precision handheld MEMS NFSs.

关键词： NFS virtual system

0.79 ppm scale-factor nonlinearity whole-angle microshell gyroscope realized by real-time calibration of capacitive displacement detection

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Microsystems & Nanoengineering 2021年第5期7卷 129-139页

作者： Jiangkun Sun Sheng Yu Yongmeng Zhang Qingsong Li Xiang Xi Kun Lu xuezhong wu Dingbang Xiao National University of Defense Technology Changsha 410073China

Whole-angle gyroscopes have broad prospects for development with inherent advantages of excellent scale factor,wide bandwidth and measurement range,which are restrictions on rate *** studies on the whole-angle mode are based mostly on the linear model of Lynch,and the essential nonlinearity of capacitive displacement detection is always neglected,which has significant negative effects on the *** this paper,a novel realtime calibration method of capacitive displacement detection is proposed to eliminate these nonlinear *** novel method innovatively takes advantage of the relationship between the first and third harmonic components of detective signals for *** on this method,the real-time calibration of capacitive displacement detection is achieved and solves the problems of traditional methods,which are usually related to the vibration amplitude,environmental variations and other ***,this novel calibration method is embedded into a whole-angle control system to restore the linear capacitive response in real time and then combined with a microshell resonator for the first time to exploit the enormous potential of an ultrahigh Q factor and symmetric *** effectiveness is proven because the angle drift is reduced significantly to improve the scale-factor nonlinearity by 14 times to 0.79 ppm with 0.0673/h bias instability and a 0.0017s rate threshold,which is the best reported performance of the MEMS whole-angle gyroscope thus *** importantly,this novel calibration method can be applied for all kinds of resonators with the requirement of a linear capacitive response even under a large resonant amplitude.

关键词： structure nonlinearity displacement

Model of NBTI combined with mobility degradation

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Journal of Semiconductors 2018年第12期39卷 141-146页

作者： xuezhong wu Chenyue Ma Shucheng Gao Xiangbin Li Fu Sun Lining Zhang Xinnan Lin The Shenzhen Key Lab of Advanced Electron Device and Integration ECE PKUSZ College of Electronic Science and Technology Shenzhen University

The mobility degradation induced by negative bias temperature instability(NBTI) is usually ignored in traditional NBTI modeling and simulation, resulting in overestimation of the circuit lifetime, especially after longterm operation. In this paper, the mobility degradation is modeled in combination with the universal NBTI *** coulomb scattering induced by interface states is revealed to be the dominant component responsible for mobility degradation. The proposed mobility degradation model fits the measured data well and provides an accurate solution for evaluating coupling of NBTI with HCI(hot carrier injection) and SHE(self-heating effect), which indicates that mobility degradation should be considered in long-term circuit aging simulation.

关键词： NBTI mobility degradation aging simulation algorithm hot carrier injection self-heating effect coupling

0.04 degree-per-hour MEMS disk resonator gyroscope with high-quality factor (510 k) and long decaying time constant(74.9 s)

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Microsystems & Nanoengineering 2018年第1期4卷 46-56页

作者： Qingsong Li Dingbang Xiao Xin Zhou Yi Xu Ming Zhuo Zhanqiang Hou Kaixuan He Yongmeng Zhang xuezhong wu College of Intelligence Science National University of Defense TechnologyChangsha 410073China Laboratory of Science and Technology on Integrated Logistics Support National University of Defense TechnologyChangsha 410073China State Key Laboratory of ASIC and System School of MicroelectronicsFudan UniversityShanghai 200433China East China Institute of Photo-Electron IC Bengbu 233042China

The disk resonator gyroscope is an attractive candidate for high-performance MEMS *** gyroscope consists of a sensor and readout electronics,and the characteristics of the sensor directly determine the *** the sensor,a high-quality factor and long decaying time constant are the most important characteristics required to achieve high *** report a disk resonator gyroscope with a measured quality factor of 510 k and decaying time constant of 74.9 s,which is a record for MEMS silicon disk resonator gyroscopes,to the best of our *** improve the quality factor of the DRG,the quality factor improvement mechanism is first analyzed,and based on this mechanism two stiffness-mass decoupled methods,i.e.,spoke length distribution optimization and lumped mass configuration design,are proposed and demonstrated.A disk resonator gyroscope prototype is fabricated based on these design strategies,and the sensor itself shows an angle random walk as low as 0.001°/√h,demonstrating true potential to achieve navigation-grade *** gyroscope with readout electronics shows an angle random walk of 0.01°/√h and a bias instability of 0.04°/h at room temperature without compensation,revealing that the performance of the gyroscope is severely limited by the readout electronics,which should be further *** expect that the quality factor improvement methods can be used in the design of other MEMS gyroscopes and that the newly designed DRG can be further improved to achieve navigation-grade performances for high-end industrial,transportation,aerospace,and automotive applications.

关键词： resonator constant attractive

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PECVD氮化硅薄膜制备工艺研究

中国机械工程 2005年第z1期16卷 396-398页

作者：李伟东吴学忠李圣怡国防科学技术大学长沙410073 国防科学技术大学长沙410073 国防科学技术大学长沙410073

通过原子力显微镜和台阶仪观察测试PECVD氮化硅薄膜的表面形貌及其在HF缓冲液中的被腐蚀速率,研究了用SiH4和NH3作反应气体时,影响PECVD氮化硅薄膜均匀性、致密性、淀积速率、被腐蚀速率的几个关键因素,并对一些常用的工艺参数进行了总结.

关键词：氮化硅薄膜等离子体增强化学气相淀积(PECVD) 原子力显微镜(AFM) 台阶仪