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A self-centering and stiffness-controlled MEMS accelerometer

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Microsystems & Nanoengineering 2024年第1期10卷 27-40页

作者： Yiming jin Zhipeng Ma Ziyi Ye Mingkang Li Xudong Zheng zhonghe jin School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310013China Key Laboratory of Micro/Nano-Satellite Research of Zhejiang Province Hangzhou 310007PR China

This paper presents a high-performance MEMS accelerometer with a DC/AC electrostatic stiffness tuning capability based on double-sided parallel plates(DSPPs).DC and AC electrostatic tuning enable the adjustment of the effective stiffness and the calibration of the geometric offset of the proof mass,respectively.A dynamical model of the proposed accelerometer was developed considering both DC/AC electrostatic tuning and the temperature *** on the dynamical model,a self-centering closed loop is proposed for pulling the reference position of the forceto-rebalance(FTR)to the geometric center of *** self-centering accelerometer operates at the optimal reference position by eliminating the temperature drift of the readout circuit and nulling the net electrostatic tuning *** stiffness closed-loop is also incorporated to prevent the pull-in instability of the tuned low-stiffness accelerometer under a dramatic temperature ***-time adjustments of the reference position and the DC tuning voltage are utilized to compensate for the residue temperature drift of the proposed *** a result,a novel controlling approach composed of a self-centering closed loop,stiffness-closed loop,and temperature drift compensation is achieved for the accelerometer,realizing a temperature drift coefficient(TDC)of approximately 7μg/℃ and an Allan bias instability of less than 1μg.

关键词： stiffness electrostatic centering

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基于圆周相关扩频信号的快速捕获改进方法

中国空间科学技术（中英文） 2024年第2期44卷 109-117页

作者：刘洁张朝杰金小军金仲和浙江大学航空航天学院杭州310027 浙江省微纳卫星研究重点实验室杭州310027

针对大多普勒频偏、低信噪比条件下长周期伪码的扩频信号捕获问题,提出了一种基于圆周相关扩频信号的快速捕获改进方法。该算法对圆周相关后的结果利用快速傅里叶变换(FFT)进行频率估计,扩大了传统圆周相关法的扫频步进,使扫频步进不再... 详细信息

针对大多普勒频偏、低信噪比条件下长周期伪码的扩频信号捕获问题,提出了一种基于圆周相关扩频信号的快速捕获改进方法。该算法对圆周相关后的结果利用快速傅里叶变换(FFT)进行频率估计,扩大了传统圆周相关法的扫频步进,使扫频步进不再受跟踪环路带宽的限制。理论分析及仿真结果表明,在信噪比为-34 dB、多普勒频率为500 kHz条件下算法可以正确地估计出伪码相位和多普勒频偏。在达到相同的灵敏度条件下,所提算法的平均捕获时间与传统的圆周相关法相比缩短了约47%,与基于FFT的并行频率搜索法相比缩短了约88%。另外,用于频率估计的FFT点数仅占圆周相关点数的1%,故额外增加的硬件资源很少。算法逻辑控制简单,尤其适用于大多普勒频偏、低信噪比及长周期伪码的卫星通信系统。

关键词：卫星通信系统直接序列扩频信号捕获圆周相关快速傅里叶变换

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MEMS加速度计全温性能优化方法

中国惯性技术学报 2024年第1期32卷 64-70页

作者：刘国文刘宇李兆涵王学锋金仲和王巍浙江大学航空航天学院杭州310027 北京航天控制仪器研究所北京100039 中国航天科技集团有限公司北京100048

针对微机电系统(MEMS)加速度计全温性能低的问题,提出锚区应力对消方法、低应力粘接工艺和温度补偿方法。首先,通过调整两个键合的锚区面积大小实现锚区应力对消,使得加速度计的温度性能得到改善;然后,建立加速度计堆叠封装模型并对专... 详细信息

针对微机电系统(MEMS)加速度计全温性能低的问题,提出锚区应力对消方法、低应力粘接工艺和温度补偿方法。首先,通过调整两个键合的锚区面积大小实现锚区应力对消,使得加速度计的温度性能得到改善;然后,建立加速度计堆叠封装模型并对专用集成电路(ASIC)粘接参数、加速度计敏感结构点胶方式与点胶参数进行仿真分析,从而确定了加速度计的低应力粘接形式和粘接工艺;最后,对加速度计零偏和标度因数设计了三阶温度补偿方法并进行了实验测试。实验结果表明,加速度计全温零偏稳定性达到47.3μg(1σ)、全温标度因数稳定性达到43.6 ppm(1σ),提高了加速度计的全温性能。

关键词： MEMS加速度计应力对消低应力粘接温度补偿

An analysis method for ISL of multilayer constellation

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Journal of Systems Engineering and Electronics 2022年第4期33卷 961-968页

作者： XU Xiaoyi WANG Chunhui jin zhonghe Micro-Satellite Research Center Zhejiang UniversityHangzhou 310027China

The multilayer satellite network has high spatial spectrum utilization, flexible networking, strong survivability, and diversified functions. The inter-satellite links(ISLs) and crosslayer ISLs(CLISLs) enable direct communication paths between satellites, which improves the spatial autonomy of the constellation. Due to the existence of perturbation, ISLs are affected for a long time, which impacts reliable inter-satellite transmission. The stability and complexity of ISL establishment are related to the static and dynamic characteristics of range and azimuth. This paper presents a model of ISLs in a perturbed multilayer constellation. Series of theoretical derivation, simulation, and numerical calculation are carried out. A more comprehensive multilayer constellation ISL model is obtained. The work of this paper provides some theoretical foundations for constellation networking research.

关键词： satellite network multilayer constellation inter-satellite link(ISL)

Camera calibration method for an infrared horizon sensor with a large field of view

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Frontiers of Information Technology & Electronic Engineering 2023年第1期24卷 141-153页

作者： Huajian DENG Hao WANG Xiaoya HAN Yang LIU zhonghe jin Micro-Satellite Research Center Zhejiang UniversityHangzhou 310027China Zhejiang Key Laboratory of Micro-nano Satellite Research Hangzhou 310027China Beijing Institute of Tracking and Telecommunications Technology Beijing 100094China

Inadequate geometric accuracy of cameras is the main constraint to improving the precision of infrared horizon sensors with a large field of view(FOV).An enormous FOV with a blind area in the center greatly limits the accuracy and feasibility of traditional geometric calibration methods.A novel camera calibration method for infrared horizon sensors is presented and validated in this *** infrared targets are used as control *** camera is mounted on a rotary *** the table rotates,these control points will be evenly distributed in the entire *** with traditional methods that combine a collimator and a rotary table which cannot effectively cover a large FOV and require harsh experimental equipment,this method is easier to implement at a low cost.A corresponding three-step parameter estimation algorithm is proposed to avoid precisely measuring the positions of the camera and the control *** are implemented with 10 infrared horizon sensors to verify the effectiveness of the calibration *** results show that the proposed method is highly stable,and that the calibration accuracy is at least 30%higher than those of existing methods.

关键词： Infrared horizon sensor Ultra-field infrared camera Camera calibration

Temperature Bias Drift Phase-Based Compensation for a MEMS Accelerometer with Stiffness-Tuning Double-Sided Parallel Plate Capacitors

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Nanomanufacturing and Metrology 2023年第3期6卷 29-40页

作者： Mingkang Li Zhipeng Ma Tengfei Zhang Yiming jin Ziyi Ye Xudong Zheng zhonghe jin School of Aeronautics and Astronautics Zhejiang UniversityHangzhou310013China Key Laboratory of Micro/Nano-Satellite Research of Zhejiang Province Hangzhou310007China

This paper reports an approach of in-operation temperature bias drift compensation based on phase-based calibration for a stiffness-tunable MEMS accelerometer with double-sided parallel plate(DSPP)*** temperature drifts of the components of the accelerometer are characterized,and analytical models are built on the basis of the measured drift *** reveal that the temperature drift of the acceleration output bias is dominated by the sensitive mechanical *** out-of-bandwidth AC stimulus signal is introduced to excite the accelerometer,and the interference with the acceleration measurement is *** demodulated phase of the excited response exhibits a monotonic relationship with the effective stiffness of the *** the proposed online compensation approach,the temperature drift of the effective stiffness can be detected by the demodulated phase and compensated in real time by adjusting the stiffness-tuning voltage of DSPP *** temperature drift coefficient(TDC)of the accelerometer is reduced from 0.54 to 0.29 mg/℃,and the Allan variance bias instability of about 2.8μg is not adversely ***,the pull-in resulting from the temperature drift of the effective stiffness can be *** can be further reduced to 0.04 mg/℃through an additional offline calibration based on the demodulated carrier phase representing the temperature drift of the readout circuit.

关键词： MEMS accelerometer Stiffness tuning Double-sided parallel plates Temperature drift compensation

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微纳卫星总剂量评估优化

北京航空航天大学学报 2024年第3期50卷 985-993页

作者：佘璇楼海君宋仁庭李琪聪金仲和浙江大学航空航天学院杭州310013 杭州电子科技大学电子信息学院杭州310018 西安卫星测控中心西安710043 浙江大学浙江省软体机器人与智能器件研究重点实验室杭州310013

针对微纳卫星在空间环境中遇到的总剂量(TID)效应,为更加准确地评估卫星内敏感点的剂量值,基于正二十面体的几何划分方法改进了传统的空间网格划分,宏观计算并验证了粒子透过材料的衰减,实现扇形角等效评估优化。围绕计算准确度和效率,... 详细信息

针对微纳卫星在空间环境中遇到的总剂量(TID)效应,为更加准确地评估卫星内敏感点的剂量值,基于正二十面体的几何划分方法改进了传统的空间网格划分,宏观计算并验证了粒子透过材料的衰减,实现扇形角等效评估优化。围绕计算准确度和效率,构建形状模型进行比较验证,通过与优化等立体角划分法、正八面体划分法的比较,表明该方法更加稳定高效,计算速度可提高6.4%,更适合评估复杂形状模型。基于改进的三维总剂量评估方法,对形状模型进行针对性总剂量防护,防护效果相较于无差别防护可提高255.1%。研究成果可有效提高微纳卫星总剂量评估效率,保障星内敏感器件在任务周期内的可靠运行,为微纳卫星总剂量防护提供重要参考。

关键词：微纳卫星空间辐射辐射防护总剂量网格划分法

Design, analysis and optimization of random access inter-satellite ranging system

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Journal of Systems Engineering and Electronics 2020年第5期31卷 871-883页

作者： XU Xiaoyi WANG Chunhui jin zhonghe Micro-Satellite Research Center Zhejiang UniversityHangzhou 310027China

In this paper, a random access inter-satellite ranging(RAISR) system is designed. The ranging accuracy is optimized by an algorithm to greatly improve the ranging accuracy. This paper verifies the feasibility of the RAISR system through a series of theoretical analysis, numerical simulation, hardware system design and testing. The research work brings the solution to the design and accuracy optimization problem of the RAISR system,which eliminates the main error caused by the satellite dynamic characteristics and frequency source drift of the RAISR *** accuracy of the measurement system has been significantly improved.

关键词： satellite ranging random access distributed network

Bipartite graph-based control flow checking for COTS-based small satellites

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Chinese Journal of Aeronautics 2015年第3期28卷 883-893页

作者： Wang Honghao Wang Huiquan jin zhonghe Micro-satellite Research Center Zhejiang University

Abstract Single event upset （SEU） effect, caused by highly energized particles in aerospace, threatens the reliability and security of small satellites composed of commercialofftheshelves （COTS）. SEU induced control flow errors （CFEs） may cause unpredictable behavior or crashes of COTSbased small satellites. This paper proposes a generic softwarebased control flow checking technique （CFC） and bipartite graphbased control flow checking （BGCFC）. To simplify the types of illegal branches, it transforms the conventional control flow graph into the equivalent bipartite graph. It checks the legal ity of control flow at runtime by comparing a global signature with the expected value and introduces consecutive IDs and bitmaps to reduce the time and memory overhead. Theoretical analysis shows that BGCFC can detect all types of internode CFEs with constant time and memory overhead. Practical tests verify the result of theoretical analysis. Compared with previous techniques, BGCFC achieves the highest error detection rate, lower time and memory overhead; the composite result in evaluation fac tor shows that BGCFC is the most effective one among all these techniques. The results in both theory and practice verify the applicability of BGCFC for COTSbased small satellites.

关键词： Bipartite graph Control flow checking Commercial-off-the-shelves(COTS) Error injection Fault tolerant Illegal branch Small satellites