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The 29th International Congress on Condition Monitoring and Diagnostic Engineering Management

作者： Wu Guoxin Xu Xiao li Huang Min Key Laboratory of Modern Measurement & Control Technology Ministry of Education Beijing Information Science &Technology University Schools of Electromechanical Engineering Beijing Information Science &Technology University

Due to the complexity of the processing environment,sensor limitations and imperfections access to information technology and other factors,Fault information of the CNC machine tools often exhibit random,imprecise,incomplete and other ***,the large-scale complicated means of acquiring information will inevitably bring about diversification,with the Upsizing and complicating of the high-grade CNC machine tools,information acquisition means becomes *** there is uncertainty in information *** at the cross and repeated uncertainty and inexactness,an imprecise reasoning method for high-grade CNC machine tool's reliability testing and troubleshooting is *** on the multi-sensor information characteristic,credibility quantity set rules of the reliability analysis is *** analyses showed that:during the high-end CNC machine tool operation reliability analysis,analysis of inaccuracies soft modal propositional rule has practical significance,and it can provide the basis for the analysis of fault diagnosis of high-grade CNC machine tools running state.

关键词： high-grade CNC machine tools operational reliability fault diagnosis inaccurate analysis

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Light scattering characteristic from particles located on a surface

Light scattering characteristic from particles located on a ...

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International Conference on Information technology and Computer Application Engineering, ITCAE 2014

作者： Gong, L. Hou, H.L. Zou, J.L. School of Photoelectric Engineering Xi’an Technological University Xi’an China Science and Technology on Electromechanical Dynamic Control Laboratory Xi’an China

ISBN: (纸本)9781138027176

Based on the Finite Difference Time Domain (FDTD) method, the Generalized Perfectly Matched Lays (GPML) can work very well against the half-space problem about the optical surface and defect particles. The connect boundary condition is reduced by the three-wave method. The reciprocity theorem is applied to the near-far field extrapolation. The angle distributions of double particles with different ratios are shown. Some selected calculations on the effects of the shape are described. © 2015 Taylor & Francis Group, London.

关键词： Finite difference time domain method

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Research on GPS-only navigation and guidance for course-correction fuze

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International Journal of Earth sciences and Engineering 2016年第3期9卷 1314-1318页

作者： Luo, Xiaolin Li, Dongguang Science and Technology on Electormechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing100081 China Mechanic and Electronic Engineering North University of China Tai yuan030051 China

In the military science of ballistics, circular error probable (CEP) is a measure of a weapon system's precision. The problem is how to calculate the CEP included measurement noise, and process noise, a Kalman filter with model replacement, and a simple navigation and control algorithms. Using an augmented state formulation, covariance techniques were used to determine the variances of CEP, The linear covariance analysis proved to be a very useful and fast analysis tool for the preliminary guidance navigation system design and analysis. © 2016 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.

关键词： Global positioning system

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Information technology for Early Fault Forecast of Wind Turbine Generator Unit

Information Technology for Early Fault Forecast of Wind Turb...

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The 29th International Congress on Condition Monitoring and Diagnostic Engineering Management

作者： Xu Xiaoli Zuo Yunbo Liu Xiuli Zhao Xiwei Key Laboratory of Modern Measurement & Control Technology of Ministry of Education key laboratory of electromechanical system measurement & control of BeijingBeijing Information Science and Technology University School of Mechanical and Vehicle Engineering Beijing Institute of Technology

This paper proposes and expatiates the information technology for early fault forecast of wind turbine generator unit based on the non-stability,non-linearity,variable working conditions,long-term operation and early fault forecast of wind turbine generator unit in respect of the early fault information acquisition and weak information analysis for wind turbine generator unit;the fault development trend information and feature extraction of wind turbine generator unit;the building of trend forecast model for wind turbine generator unit;and the research & development of wind turbine generator unit state monitoring and fault forecast system,*** to experimental studies and field verification,the multi-information fusion,the intelligent information analysis and decisionmaking,and the establishment of wind turbine generator unit fault forecast system and the application remote network in predictive maintenance center for unit group on wind farm,etc.,and help to improve the accuracy,pertinence and suitability of processing of mult forecast information,and carry out rational maintenance and dynamic management thereof.

关键词： Wind turbine generator unit state monitoring fault forecast safety guarantee information technology

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On the temperature-related mechanical properties of UV-LIGA nickel material

On the temperature-related mechanical properties of UV-LIGA ...

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16th Annual Conference and 5th International Conference on Chinese Society of Micro-Nano technology, CSMNT 2014

作者： Yuan, Shuangshi He, Guang Zhang, Ming Li, Guozhong National Key Laboratory on Electromechanical Dynamic Control Beijing Institute of Technology Beijing100081 China

ISBN: (纸本)9783038354628

MEMS nickel material is commonly used for structural material in micro devices. In order to study the effect of environmental temperature on its mechanical properties,this paper has built up a experimental system which can measure the temperature-related static mechanical parameters of the UV-LIGA nickel material. By using the system for uniaxial tensile experiments of the micro specimen under different temperature, the stress-strain curves of the micro specimen under different temperature were obtained;the mechanical parameters of the micro specimen such as elastic modulus, yield stress and failure stress under different temperature were also calculated out;Finally, the relationship between temperature and mechanical parameters including elastic modulus, yield stress and failure stress was analyzed. © (2015) Trans Tech Publications, Switzerland.

关键词： Yield stress

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On two asymmetry wake patterns behind two side-by-side square cylinders

On two asymmetry wake patterns behind two side-by-side squar...

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第二届全球华人水动学学术会议

作者： Wei Zhang Xiaodong Bai Science and Technology on Water Jet Propulsion Laboratory Marine design and research institute of China Ministry of Education Key laboratory of Structural Dynamic Behavior and Control School of Civil EngineeringHarbin Institute of Technology

Several asymmetric wake patterns are discovered for flow behind two side-by-side circle *** present work extends previous researches to study flow behind two side-by-side square cylinders with focus on two types of asymmetric wake flow,namely deflected oscillatory wake and flip-flop,which are believed to be of the same *** combination of the direct numerical simulation by lattice Boltzmann method(DNS-LBM) and the state-of-art dynamic mode decomposition(DMD) is used to explore the underlying physics of the *** types of asymmetric wake patterns are presented in the wake like the wake of a pair of circle *** is confirmed that the deflection of the wake is not of Coanda ***,the dynamic modes of the flows are extracted from the numerical *** comparing the corresponding modes,it is found here the two types of flow are of different mechanism.

关键词： Wake flow pattern Side-by-side cylinder DMD DNS-LBM

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Optimization of quadrature error correction method for silicon MEMS gyroscopes

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Guangxue Jingmi Gongcheng/Optics and Precision Engineering 2016年第1期24卷 134-142页

作者： Cao, Hui-Liang Wang, Yu-Liang Shi, Yun-Bo Shen, Chong Li, Hong-Sheng Liu, Jun Yang, Zhi-Cai Science and Technology on Electronic Test & Measurement Laboratory North University of China Taiyuan030051 China Key Laboratory of Instrumentation Science and Dynamic Measurement of the Ministry of Education North University of China Taiyuan030051 China Beijing Institute of Aerospace Control Devices Beijing100094 China School of Instrument Science and Engineering Southeast University Nanjing210096 China

This paper focuses on finding out a optimum quadrature error correction method for a dual-mass Micro-electro-mechanical System (MEMS) gyroscope with quadrature error correction combs and sense feedback combs. The structure of the gyroscope was introduced, and influences of quadrature errors on the output signals were simulated and quantized. The results show that quadrature error equivalent angular rate is 200(°)/s and the demodulation phase error is less than 2°, which generates 15(°)/s variation of output signal. Three kinds of quadrature error correction methods used commonly in measuring this structure were investigated, and they are Charge Injecting Method (CIM), Quadrature Force Correction Methods (QFCM) and Quadrature Coupling Stiffness Correction Method (QCSCM). The feasibility of the three method was verified in theory. A gyroscope without quadrature error correction was tested, the results show that the quadrature signal peak-peak amplitudes from left and right mass preamplifiers are 150 mV and 300 mV respectively. Then, the correction method based on left mass and right mass independently was proposed. The the experiments based on CIM, QFCM and QCSCM were performed. The results show that the quadrature error signals are eliminated basically, their bias values and bias stabilities are -8.361(°)/s and 423(°)/h, 2.419(°)/s and 82(°)/h, 1.751(°)/s and 25(°)/h, respectively. According to the results, the QCSCM is verified to be the optimal method for quadrature error correction, and the theory analysis result is correct. © 2016, science Press. All right reserved.

关键词： Silicon

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Improving on HEED protocol of wireless sensor networks with sleep scheduling algorithm

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Journal of Information and Computational science 2015年第13期12卷 5163-5173页

作者： Duan, Yabo Song, Chengtian Xu, Lixin Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing China

Wireless Sensor Networks together hundreds or thousands of sensors allow users to monitor a remote areas. Improving energy efficiency while ensuring a certain coverage ratio in Wireless Sensor Networks (WSNs) is an extremely challenging issue. In some long-term monitoring applications of WSNs, where full coverage is not required, nodes can go to sleep mode to reduce energy consumption and increase network lifetime. In this paper, we propose three sleep scheduling algorithms based on HEED (Hybrid Energy-Efficient Distributed clustering) algorithm: Fixed Node Degree (FND) algorithm, dynamic Node Degree (DND) algorithm and dynamic Node Degree combined with Remaining Energy (DNDRE) algorithm. Our primary goal is to maximize the network lifetime while guaranteeing coverage ratio of the entire WSNs. Furthermore, we propose a simple and practical coverage ratio calculation method. We find the DNDRE performs the best in three sleep scheduling algorithms. ©, 2015, Journal of Information and Computational science. All right reserved.

关键词： Scheduling algorithms

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Back-stepping robust trajectory linearization control for hypersonic reentry vehicle via novel tracking differentiator

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Journal of the Franklin Institute 2016年第9期353卷 1957-1984页

作者： Xingling Shao Honglun Wang Key Laboratory of Instrumentation Science & Dynamic Measurement Ministry of Education North University of China Taiyuan 030051 China National Key Laboratory for Electronic Measurement Technology School of Instrument and Electronics North University of China Taiyuan 030051 China School of Automation Science and Electrical Engineering Beihang University Beijing 100191 China Science and Technology on Aircraft Control Laboratory Beihang University Beijing 100191 China

This paper proposes a back-stepping robust trajectory linearization control (TLC) design for hypersonic reentry vehicle (HRV) attitude tracking problem from a novel tracking differentiator perspective. First, the attitude kinematics and dynamics for HRV is formulated and rewritten in feedback form with mismatched and matched uncertainties introduced by variations of various aerodynamic coefficients . Second, a sigmoid function based novel tracking differentiator (STD) with global fast convergence property , simple structure and chattering-free in differential estimation is developed to handle the “explosion of term” problem in back-stepping TLC design. In addition, dynamical performance and noise-attenuation ability of STD are analyzed in frequency domain by describing function method. Third, how to convert between sigmoid function based disturbance observer (SDO) and STD is given, and based on the estimates of uncertainties provided by SDO in attitude and angular rate loop, the back-stepping robust TLC is synthesized to track the respective commands in dual-loop. Then, the stability of the composite SDO-enhanced back-stepping TLC approach is established. Finally, extensive simulation results are presented to demonstrate the effectiveness of the proposed control strategy in improving disturbance attenuation ability and performance robustness against multiple uncertainties.

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Simulations of the transient electromagnetic field in exploding foil initiator

Simulations of the transient electromagnetic field in explod...

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IEEE Advanced Information technology, Electronic and Automation control Conference, IAEAC 2015

作者： Baoyue, Zhang Song, Zheng Xingguo, Kang Xi'an Institute of Electromechanical Information Technology Science and Technology on Electromechnical Dymanic Control Laboratory Xi'an China Xi'An Institute of Electromechanical Information Technology Xi'an China

ISBN: (纸本)9781479919796

A special high pulsed current is required in the Exploding Foil Initiator (EFI). The pulsed current would reach several thousand amperes, and this process will arouse strong electromagnetic interference (EMI) to the control units near around. Ever since EFI's appearance, it has been designed with the targets of lower volume, higher integration, energy and cost effectiveness. Thus, this strong EMI is a bottleneck of the miniaturization development of EFI. In this paper, the characteristic curve of the pulsed current was calculated out, and then loaded on the equivalent wire of the circuit. The transient electromagnetic field around the conducting wire has been simulated out for the first time. The variation of induced electric field (EF) in different directions was plotted. All the 3D models and simulations are carried out using the Finite Element Method (FEM) software-ANSYS. Besides, the simulation result has been verified through a designed test. The final conclusions obtained in this work are highly meaningful for the EMI protection of EFI. Based on the data of radiated EMF, further protection method of different electronic components can be analyzed according to their thresholds. © 2015 IEEE.

关键词： Cost effectiveness

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