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Journal of Systems Engineering and Electronics 2024年第1期35卷 65-73页

作者： WEN Yi WANG Junxiang XU Hongbing School of automatic Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Beijing institute of Aerospace Systems Engineering Beijing 100076China

Large calculation error can be formed by directly employing the conventional Yee’s grid to curve surfaces.In order to alleviate such condition,unconditionally stable CrankNicolson Douglas-Gunn(CNDG)algorithm with is proposed for rotationally symmetric multi-scale problems in anisotropic magnetized plasma.Within the CNDG algorithm,an alternative scheme for the simulation of anisotropic plasma is proposed in body-of-revolution domains.Convolutional perfectly matched layer(CPML)formulation is proposed to efficiently solve the open region problems.Numerical example is carried out for the illustration of effectiveness including the efficiency,resources,and absorption.Through the results,it can be concluded that the proposed scheme shows considerable performance during the simulation.

关键词： anisotropic magnetized plasma body-of-revolution(BOR) Crank-Nicolson Douglas-Gunn(CNDG) finite-difference time-domain(FDTD) perfectly matched layer(PML) rotationally symmetric multi-scale problems

Continuous Robust Control for Series Elastic Actuator With Unknown Payload Parameters and External Disturbances

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IEEE/CAA Journal of automatica Sinica 2017年第4期4卷 620-627页

作者： Meng Wang Lei Sun Wei Yin Shuai Dong Jingtai Liu institute of Robotics and automatic Information System Nankai University Tianjin Key Laboratory of Intelligent Robotics Nankai University IEEE

In this paper, the torque tracking control problem for a class of series elastic actuators(SEAs) in the presence of unknown payload parameters and external disturbances is investigated. The uncertainties/disturbances rejection problem for SEAs is addressed from the view of a continuous nonlinear robust control development. Specifically, based on the analysis of a nonlinear SEA, the generic dynamics of SEA systems is described and a novel nonlinear control framework for SEAs is constructed. Then a RISE(robust integral of the sign of the error)-based second-order filter is introduced to synthesize the control law. Moreover, the control performance is theoretically ensured by Lyapunov analysis. Finally, some experimental results are included to demonstrate the superior performance of the proposed control method, in terms of transient response and robustness.

关键词： Nonlinear robust control torque control series elastic actuator

LFM Radar Source Passive Localization Algorithm Based on Range Migration

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Journal of Beijing institute of Technology 2024年第2期33卷 130-140页

作者： Dandan Li Deyi Wang Hao Huan Beijing Key Laboratory of Fractional Signals and Systems School of Information and ElectronicsBeijing Institute of TechnologyBeijing 100081China Beijing Aerospace automatic Control institute Beijing 100854China

Traditional single-satellite passive localization algorithms are influenced by frequency and angle measurement accuracies,resulting in error estimation of emitter position on the order of kilometers.Subsequently,a single-satellite localization algorithm based on passive synthetic aper-ture(PSA)was introduced,enabling high-precision positioning.However,its estimation of azimuth and range distance is considerably affected by the residual frequency offset(RFO)of uncoopera-tive system transceivers.Furthermore,it requires data containing a satellite flying over the radia-tion source for RFO search.After estimating the RFO,an accurate estimation of azimuth and range distance can be carried out,which is difficult to achieve in practical situations.An LFM radar source passive localization algorithm based on range migration is proposed to address the dif-ficulty in estimating frequency offset.The algorithm first provides a rough estimate of the pulse repetition time(PRT).It processes intercepted signals through range compression,range interpola-tion,and polynomial fitting to obtain range migration observations.Subsequently,it uses the changing information of range migration and an accurate PRT to formulate a system of nonlinear equations,obtaining the emitter position and a more accurate PRT through a two-step localization algorithm.Frequency offset only induces a fixed offset in range migration,which does not affect the changing information.This algorithm can also achieve high-precision localization in squint scenar-ios.Finally,the effectiveness of this algorithm is verified through simulations.

关键词： passive localization range migration residual frequency offset

Real-time UAV path planning based on LSTM network

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Journal of Systems Engineering and Electronics 2024年第2期35卷 374-385页

作者： ZHANG Jiandong GUO Yukun ZHENG Lihui YANG Qiming SHI Guoqing WU Yong School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China The Flight automatic Control Research institute of AVIC Xi’an 710065China Military Representative Office of Marine Wuhan Bureau in Luoyang Area Luoyang 471000China

To address the shortcomings of single-step decision making in the existing deep reinforcement learning based unmanned aerial vehicle(UAV)real-time path planning problem,a real-time UAV path planning algorithm based on long shortterm memory(RPP-LSTM)network is proposed,which combines the memory characteristics of recurrent neural network(RNN)and the deep reinforcement learning algorithm.LSTM networks are used in this algorithm as Q-value networks for the deep Q network(DQN)algorithm,which makes the decision of the Q-value network has some memory.Thanks to LSTM network,the Q-value network can use the previous environmental information and action information which effectively avoids the problem of single-step decision considering only the current environment.Besides,the algorithm proposes a hierarchical reward and punishment function for the specific problem of UAV real-time path planning,so that the UAV can more reasonably perform path planning.Simulation verification shows that compared with the traditional feed-forward neural network(FNN)based UAV autonomous path planning algorithm,the RPP-LSTM proposed in this paper can adapt to more complex environments and has significantly improved robustness and accuracy when performing UAV real-time path planning.

关键词： deep Q network path planning neural network unmanned aerial vehicle(UAV) long short-term memory(LSTM)

All laser direct writing process for temperature sensor based on graphene and silver

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Frontiers of Optoelectronics 2024年第1期17卷 45-55页

作者： Qi Li Ruijie Bai Lianbo Guo Yang Gao Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237China North automatic Control Technology institute Taiyuan 030006China Wuhan National Laboratory for Optoelectronics Huazhong University of Science&TechnologyWuhan 430074China

A highly sensitive temperature sensing array is prepared by all laser direct writing(LDW)method,using laser induced silver(LIS)as electrodes and laser induced graphene(LIG)as temperature sensing layer.A finite element analysis(FEA)photothermal model incorporating a phase transition mechanism is developed to investigate the relationship between laser parameters and LIG properties,providing guidance for laser processing parameters selection with laser power of 1–5 W and laser scanning speed(greater than 50 mm/s).The deviation of simulation and experimental data for widths and thickness of LIG are less than 5%and 9%,respectively.The electrical properties and temperature responsiveness of LIG are also studied.By changing the laser process parameters,the thickness of the LIG ablation grooves can be in the range of 30–120μm and the resistivity of LIG can be regulated within the range of 0.031–67.2Ω・m.The percentage temperature coefficient of resistance(TCR)is calculated as−0.58%/°C.Furthermore,the FEA photothermal model is studied through experiments and simulations data regarding LIS,and the average deviation between experiment and simulation is less than 5%.The LIS sensing samples have a thickness of about 14μm,an electrical resistivity of 0.0001–100Ω・m is insensitive to temperature and pressure stimuli.Moreover,for a LIS-LIG based temperature sensing array,a correction factor is introduced to compensate for the LIG temperature sensing being disturbed by pressure stimuli,the temperature measurement difference is decreased from 11.2 to 2.6°C,indicating good accuracy for temperature measurement.

关键词： Laser direct writing Temperature sensor Finite element analysis Laser induced graphene Laser induced silver

Hierarchically Distributed Optimization with a Flexible and Complexity-Reducing Algorithm

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Journal of Systems Science & Complexity 2024年

作者： LIANG Shu ZHANG Lei WEI Yiheng LIU Yemo 1.Department of Control Science and Engineering, Tongji University 2.Shanghai Research institute for Intelligent Autonomous Systems 3.School of Mathematics, Southeast University 4.Beijing Aerospace automatic Control institute Department of Control Science and Engineering Tongji University Shanghai Research institute for Intelligent Autonomous Systems School of Mathematics Southeast University Beijing Aerospace automatic Control institute

In this paper, the authors consider distributed convex optimization over hierarchical networks. The authors exploit the hierarchical architecture to design specialized distributed algorithms so that the complexity can be reduced compared with that of non-hierarchically distributed algorithms.To this end, the authors use local agents to process local functions in the same manner as other distributed algorithms that take advantage of multiple agents' computing resources. Moreover, the authors use pseudocenters to directly integrate lower-level agents' computation results in each iteration step and then share the outcomes through the higher-level network formed by pseudocenters. The authors prove that the complexity of the proposed algorithm exponentially decreases with respect to the total number of pseudocenters. To support the proposed decomposition-composition method for agents and pseudocenters, the authors develop a class of operators. These operators are generalizations of the widely-used subgradient based operator and the proximal operator and can be used in distributed convex optimization. Additionally, these operators are closed with respect to the addition and composition operations; thus, they are suitable to guide hierarchically distributed design and analysis. Furthermore,these operators make the algorithm flexible since agents with different local functions can adopt suitable operators to simplify their calculations. Finally, numerical examples also illustrate the effectiveness of the method.

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Four-Degree-of-Freedom Course Stability of an Air Cushion Vehicle

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Journal of Shanghai Jiaotong university(Science) 2010年第2期15卷 163-167页

作者：卢军黄国樑李姝芝 State Key Laboratory of Ocean Engineering Shanghai Jiaotong University Beijing Research institute of automatic Control Equipment

A four-degree-of-freedom mathematical model was established to investigate the course stability of an air cushion vehicle (ACV). The forces of aerodynamic,propeller and rudder were obtained by wind tunnel experiments. A series of constrained model experiments with horizontal-planar-motion-mechanism (HPMM) were conducted to determine the hydrodynamics. The ACV's course stability was analyzed by using Hurwitz deter-mination method with differential equation of perturbation,and the four-degree-of-freedom course stability was then checked by simulated calculation. The analysis and simulation results show that the course stability of fourdegree-of-freedom is applicable to ACV and is stricter than that of two-degree-of-freedom.

关键词： air cushion vehicle (ACV) four-degree-of-freedom course stability model experiment

A Study of Maneuvering Control for an Air Cushion Vehicle Based on Back Propagation Neural Network

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Journal of Shanghai Jiaotong university(Science) 2009年第4期14卷 482-485页

作者：卢军黄国樑李姝芝 State Key Laboratory of Ocean Engineering Shanghai Jiaotong University Beijing Research institute of automatic Control Equipment

A back propagation (BP) neural network mathematical model was established to investigate the maneuvering control of an air cushion vehicle (ACV). The calculation was based on four-freedom-degree model experiments of hydrodynamics and aerodynamics. It is necessary for the ACV to control the velocity and the yaw rate as well as the velocity angle at the same time. The yaw rate and the velocity angle must be controlled correspondingly because of the whipping, which is a special characteristic for the ACV. The calculation results show that it is an effcient way for the ACV’s maneuvering control by using a BP neural network to adjust PID parameters online.

关键词： BP神经网络车辆控制气垫车辆机动控制计算结果空气动力学 PID参数奥地利

Construction Method of Civil Aircraft Airborne⁃system Supplier Development Process System

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International Journal of Plant Engineering and Management 2024年第2期29卷 65-77页

作者： PU Youhua LI Lin LI Li AVIC Xi′an Flight automatic Control Research institute Xi′an 710076China

Based on the analysis of the development process system status of domestic and foreign civil aircraft airborne system suppliers,this paper proposes the overall construction idea of"a set of civil aircraft process system"based on IPD(Integrated product development)in the organization.The development stage,process,activity and task are the logical framework elements of the system construction."Based on process decomposition,vertical stratification,horizontal segmentation,combination of special and common,process customized to tools,role and process integration,giving full consideration to the interface between supplier management and process modules"etc.are the concrete ideas.Moreover,formulate top⁃level system construction standards,implemented by process system management tool platform,so that the process system and development work can be effectively integrated to effectively guide the development work of airborne system suppliers,and meet the quality and airworthiness requirements of civil aircraft development.Through the development application of a certain type of flight control system,the process system and tool platform were verified and optimized in practice.

关键词： development process system development assurance process integrated product development(IPD) development stage activity

Design of MC9 Test Equipment for Inertial Reference System

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International Journal of Plant Engineering and Management 2024年第2期29卷 115-128页

作者： ZHANG Haowen GUAN Hongyang WANG Shuangjia AVIC Xi′an Flight automatic Control Research institute Xi′an 710076China

Inertial reference system is one of the airborne equipment.According to the requirements of SAE ARP4754A Guidelines for Development of Civil Aircraft and Systems,MC9 equipment qualification test is needed to verify that the inertial reference system can perform reservation function under specified service conditions.That is,the inertial reference system shall pass certain environmental tests specified in DO⁃160G.Some tests are faced with the problem that the test equipment should have the function requirements of isolation protection and load simulation.Therefore,a kind of test equipment which can provide isolation protection and simulate load function in the test is designed.

关键词： inertial reference system MC9 isolation protection simulated load