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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 760-781页

作者： Dingxin He HaoPing Wang Yang Tian Yida Guo the School of Automation Nanjing University of Science and TechnologyNanjing 210094China IEEE norinco group institute of navigation and control technology Beijing 100089China

This paper proposes an adaptive neural network sliding mode control based on fractional-order ultra-local model for n-DOF upper-limb exoskeleton in presence of uncertainties,external disturbances and input *** the model complexity and input deadzone,a fractional-order ultra-local model is proposed to formulate the original dynamic system for simple controller ***,the control gain of ultra-local model is considered as a *** fractional-order sliding mode technique is designed to stabilize the closed-loop system,while fractional-order time-delay estimation is combined with neural network to estimate the lumped ***,a fractional-order ultra-local model-based neural network sliding mode controller(FO-NNSMC) is ***,to avoid disadvantageous effect of improper gain selection on the control performance,the control gain of ultra-local model is considered as an unknown ***,the Nussbaum technique is introduced into the FO-NNSMC to deal with the stability problem with unknown ***,a fractional-order ultra-local model-based adaptive neural network sliding mode controller(FO-ANNSMC) is ***,the stability analysis of the closed-loop system with the proposed method is presented by using the Lyapunov ***,with the co-simulations on virtual prototype of 7-DOF iReHave upper-limb exoskeleton and experiments on 2-DOF upper-limb exoskeleton,the obtained compared results illustrate the effectiveness and superiority of the proposed method.

关键词： Adaptive control input deadzone model-free control n-DOF upper-limb exoskeleton neural network

Numerical simulation research on multiphase flow of aviation centrifugal pump based on OpenFOAM

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Chinese Journal of Aeronautics 2024年第4期37卷 256-275页

作者： Xianwei LIU Jiangfeng FU Junjie YANG Dewen YIN Zhenhua ZHOU Huacong LI College of Power and Energy Northwestern Polytechnical UniversityXi’an 710072China norinco group Testing and Research institute Huayin 714200China AECC Xi’an Engine control technology Co.Ltd. Xi’an 710077China AECC Guizhou Honglin Aero Engine control technology Co.Ltd. Guiyang 550009China

This paper aims to tackle the calculation efficiency problem raised in the cavitation-flow simulation of the aviation centrifugal pump due to the fading-away interface resulting from the dissipation of numerics used in the phase-change control equation for unstructured-grid multiphase flow,and due to the limitation of flow time-step in whole flow regimes,the control equation of vapor–liquid two-phase flow considering cavitation mass transport is established firstly,modifying the momentum equation by introducing the surface tension,and adding the artificial convective flow to the phase equation to solve the numerical dissipation ***,in consideration of the local time step principle and based on the multi-dimensional general limiter algorithm with explicit solutions under the OpenFOAM platform,a solution method of steady-state VOF (Volume of Fluid) model considering cavitation two-phase change is constructed,and the feasibility of this method is verified by NACA hydrofoil and NASA flat plate ***,based on the platform developed,the cavitation performance of an aviation centrifugal pump inducer is *** research results show that the error of the calculated cavitation pressure distribution for NACA hydrofoil between the simulation test and the experimental-test is less than 5%,and the maximum error of calculated cavitation number at pump head dropping for NASA high-speed flat plate inducer between the simulation test and the experimental-test is 2.1%.The cavitation area observed in the simulation test is the same as that obtained in the high-speed photography *** on the OpenFOAM simulation method,the position of pump head dropping of the fuel centrifugal pump can be accurately *** error of the calculated cavitation number at pump head dropping between the simulation test and the experimental test is about 3.7%,showing high calculation accuracy.

关键词： Aero engine Fuel centrifugal pump Multiphase flow OpenFOAM Volume of fluid

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辐照缺陷装饰位错是否会导致硬化?

Acta Mechanica Sinica 2024年第2期40卷 259-267页

作者：崔嵬刘伟崔一南 navigation and control technology Research institute of China North Industries group Corporation Limited Beijing100089China School of Materials Science and Engineering Tsinghua UniversityBeijing100084China Applied Mechanics Lab. School of Aerospace EngineeringTsinghua UniversityBeijing100084China

纳米尺寸的辐照缺陷常常会在位错线附近聚集,形成装饰效应.研究者通常采用级联诱导源硬化模型描述装饰效应引起的辐照硬化.本研究工作发现不可动辐照缺陷装饰位错会导致辐照硬化,硬化程度与理论模型预测一致.然而,当装饰辐照缺陷可动时... 详细信息

纳米尺寸的辐照缺陷常常会在位错线附近聚集,形成装饰效应.研究者通常采用级联诱导源硬化模型描述装饰效应引起的辐照硬化.本研究工作发现不可动辐照缺陷装饰位错会导致辐照硬化,硬化程度与理论模型预测一致.然而,当装饰辐照缺陷可动时,则不发生辐照硬化,甚至发生软化,这种硬化消失是由于位错环始终处于与位错线相互作用力近似为零的区域,并与位错线发生关联运动.该工作带来了对辐照缺陷装饰效应和辐照硬化的新理解.

关键词：相互作用力辐照硬化辐照缺陷装饰效应硬化模型位错环纳米尺寸模型预测

Multi-Source Adaptive Selection and Fusion for Pedestrian Dead Reckoning

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IEEE/CAA Journal of Automatica Sinica 2022年第12期9卷 2174-2185页

作者： Yuanxun Zheng Qinghua Li Changhong Wang Xiaoguang Wang Lifeng Hu norinco group Air Ammunition Research institute Harbin 150030China the Research Center of Space control and Inertial technology Harbin Institute of TechnologyHarbin 150001China Research Center of Space control and Inertial technology Harbin Institute of TechnologyHarbin 150001China

Accurate multi-source fusion is based on the reliability, quantity, and fusion mode of the sources. The problem of selecting the optimal set for participating in the fusion process is nondeterministic-polynomial-time-hard and is neither sub-modular nor super-modular. Furthermore, in the case of the Kalman filter(KF) fusion algorithm, accurate statistical characteristics of noise are difficult to obtain, and this leads to an unsatisfactory fusion result. To settle the referred cases, a distributed and adaptive weighted fusion algorithm based on KF has been proposed in this paper. In this method, on the basis of the pseudo prior probability of the estimated state of each source, the reliability of the sources is evaluated and the optimal set is selected on a certain threshold. Experiments were performed on multi-source pedestrian dead reckoning for verifying the proposed algorithm. The results obtained from these experiments indicate that the optimal set can be selected accurately with minimal computation, and the fusion error is reduced by 16.6% as compared to the corresponding value resulting from the algorithm without *** proposed adaptive source reliability and fusion weight evaluation is effective against the varied-noise multi-source fusion system, and the fusion error caused by inaccurate statistical characteristics of the noise is reduced by the adaptive weight *** proposed algorithm exhibits good robustness, adaptability,and value on applications.

关键词： Adaptive reliability evaluation adaptive weight evaluation Kalman filter(KF) multi-source fusion optimal set selection

Modeling the optimal compensation capacitance of a giant magnetostrictive ultrasonic transducer with a loosely-coupled contactless power transfer system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第10期23卷 757-770页

作者： Tian LAN Ping-fa FENG Jian-jian WANG Jian-fu ZHANG Hui-lin ZHOU State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBejing 100084China'China China Ordnance Industry navigation and control technology Research institute Beijing 10089China

The giant magnetostrictive rotary ultrasonic processing system(GMUPS)with a loosely-coupled contactless power transfer(LCCPT)has emerged as a high-performance technique for the processing of hard and brittle materials,owing to its high power density.A capacitive compensation is required to achieve the highest energy efficiency of GMUPS to provide sufficient vibration amplitude when it works in the resonance *** this study,an accurate model of the optimal compensation capacitance is derived from a new electromechanical equivalent circuit model of the GMUPS with LCCPT,which consists of an equivalent mechanical circuit and an electrical *** phase lag angle between the mechanical and electrical circuits is established,taking into account the non-negligible loss in energy conversion of giant magnetostrictive material at ultrasonic *** change of system impedance characteristics and the effectiveness of the system compensation method under load are *** idle vibration experiments and machining tests are conducted to verify the developed *** results show that the GMUPS with optimal compensation capacitance can achieve the maximum idle vibration amplitude and smallest cutting *** addition,the effects of magnetic conductive material and driving voltages on the phase lag angle are also evaluated.

关键词： Rotary ultrasonic machining Giant magnetostrictive transducer(GMT) Loosely-coupled contactless power transfer(LCCPT) Electromechanical equivalent circuit Optimal compensation capacitance

Optimal Motion Planning of the Space Manipulator for Minimum Reaction Torque to Satellite

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Journal of Harbin institute of technology(New Series) 2022年第2期29卷 81-91页

作者： Zhiqiang Xu Xiangxin Zeng Jinghui Li Zhaoyan Jia norinco group Air Ammunition Research institute Co. Ltd.Harbin 150030China

For the problem of free⁃floating space robot(FFSR)that the motion of manipulator will cause a large disturbance to the attitude of satellite,a path planning method based on hp⁃adaptive Gauss pseudospectral method(hp⁃AGPM)is proposed in this *** this method,the minimum reaction torque acting on satellite is taken as the objective function,and the number of segments and the order of polynomial in each segment are determined adaptively to improve the accuracy and the efficiency of the *** the same time,the theoretical convergence of the designed method is innovatively proved to ensure that the solution of the discretized nonlinear programming(NLP)problem is the optimal solution to the original optimal *** simulation results of a planar two degree⁃of⁃freedom(2⁃DOF)space manipulator show that the proposed path planning method is more effective than the resolved acceleration control(RAC)method and the control variable parameterization(CVP)method,and is better than other pseudospectral methods both in computation speed and the number of collocation points.

关键词： free⁃floating space robot hp-adaptive Gauss pseudospectral method path planning nonlinear programming

Event-Triggered Consensus for Discrete-Time Multi-agent Systems with Parameter Uncertainties Based on a Predictive control Scheme

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Journal of Systems Science & Complexity 2020年第3期33卷 706-724页

作者： LIU Xiaoyu XUAN Yongbo ZHANG Zhongyu DIAO Zhaoshi MU Zhenxing LI Zhitao China North Industries group Corporation Limited China Ordnance Industry navigation and control technology institute Beijing 100821China Beijing Aeronuatical technology Research Center Beijing 100076China

In this paper,the event-triggered consensus for linear discrete-time multi-agent systems with parameter uncertainties is *** parameter uncertainty is assumed to be *** event-triggered consensus protocol based on the predictive control method is proposed to make the multi-agent system achieve *** for the design of the consensus protocol,the problem of estimating the control input is transformed into the problem of estimating state differences between ***,the event-triggered consensus protocol proposed in this paper only demands each agent to mornitor its state to determine its event-triggered instants.A sufficient existence condition for the consensus protocol is proposed based on the linear matrix *** a sufficient condition for the nonexistence of the Zeno-like behaviour is also ***,a numerical example is given to illustrate that the event-triggered consensus protocol proposed in this paper can make the multi-agent system with parameter uncertainties achieve consensus effectively.

关键词： Consensus event-triggered strategy multi-agent systems predictive scheme

Quantification of CP4-EPSPS in genetically modified Nicotiana tabacum leaves by LC-MS/MS with ^(18)O-labeling

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Journal of Beijing institute of technology 2015年第2期24卷 277-284页

作者：张玫鄯科明徐伟林凡凯邓玉林 State Key Laboratory for Infectious Disease Prevention and control National institute of Communicable Diseases control and Prevention Chinese Center for Disease Control and Prevention School of Life Science Beijing Institute of Technology Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases Planning and Research institute Norinco Group

The CP4-EPSPS gene is widely used in herbicide-tolerant plants/crops all over the world. In this study, a method was developed by coupling liquid chromatography with high sensitivity to tandem mass spectrometry to quantify the amount of CP4-EPSPS expression in Nicotiana tabacum leaves. The quantification of protein was converted to measure the unique peptide of CP4-EPSPS protein. One peptide unique to CP4-EPSPS was synthesized and labeled with.H2^18O to get 180 stable isotope labeled peptide. The peptide served as the internal standard. The validated method had good specificity and linearity. The intra-and inter-day precisions and accuracy for all samples were satisfactory. The results demonstrated that the novel method was sensitive and selective to quantify CP4- EPSPS in the crude extract without time-consuming pre-separation *** purification procedures.

关键词： CP4-EPSPS absolute quantification ^18O-labeling MRM

Novel approach for active vibration control of a flexible missile

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Defence technology（防务技术） 2020年第4期16卷 956-967页

作者： Cheng-long Pan Ji-li Rong Tian-fu Xu Da-lin Xiang School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China norinco group Aviation Ammunition Research institute Harbin 150030China Beijing institute of Astronautical Systems Engineering Beijing 100076China

This paper investigates the feasibility of using an active dynamic vibration absorber(ADVA) for active vibration control of a flexible missile system through *** on the principles of a dynamic vibration absorber(DVA),a ring-type ADVA is first designed to attenuate the elastic vibration of the flexible missile,and the design of the active controller adopts the proportional-integral-derivative(PID)control *** motion equations of a flexible missile with an ADVA,which is subjected to follower thrust at its aft end,are derived using the Lagrangian *** the minimum of the root mean square(RMS) of the lateral displacement response of the center of mass as the objective function,a genetic algorithm(GA) is used to optimize the parameter of the DVA and PID *** numerical calculations show that the ADVA and DVA are effective in suppressing the vibration and provide approximately 41.2% and 17.6% improvement,respectively,compa red with the case of no DVA,The ADVA has better performance than the DVA,When the missile is subjected to follower thrust,the effect of vibration reduction is more effective than the case without follower *** is feasible to reduce vibration and improve the stability of flexible missiles by means of the ADVA.

关键词： Flexible missile PID controller Active dynamic vibration absorber Genetic algorithms

Two types of coaxial self-balancing robots

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Journal of Central South University 2013年第11期20卷 2981-2990页

作者：高学山戴福全李潮全 School of Mechatronical Engineering Beijing Institute of Technology State Key Laboratory of Robotics and System (Harbin institute of technology) School of Mechanical and Automotive Engineering Fujian University of Technology navigation and control institute of China North Industries group Corporation

Two types of coaxial self-balancing robots(CSBR)were proposed,one can be used as a mobile robot platform for parts transporting in unmanned factory or as an inspector in dangerous areas,and the other can be used as a personal transporter ridden in *** designing and control structures as well as control strategies were described and compared in order to get a general way to develop such robots.A state feedback controller and a fuzzy controller were designed for the robot using DC servo motors and the robot using torque motors,*** experiments indicate that the robots can realize various desired operations smoothly and agilely at the velocity of 0.6 m/s with an operator of 65 ***,the robustness of the controllers is revealed since these controllers can stabilize the robot even with unknown external disturbances.

关键词：移动机器人自平衡同轴类型模糊控制器状态反馈控制器直流伺服电机机械设计