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第43届中国控制会议

作者： Heng Li Jianglong Yu Jiapei Zheng Yikun Yang Xiwang Dong Qingke Tan Rui Lv Yanyan Wang Institute of Artificial Intelligence Beihang University School of Automation Science and Electrical Engineering Beihang University Institute of Unmanned System Beihang University China Academy of Launch Vehicle Technology Beijing Research Institute of Mechanical and Electric Technology

ISBN: (数字)9789887581581

ISBN: (纸本)9798350366907

This paper investigates the problem of intercepting a maneuvering target at a designated impact ***,a guidance model for intercepting a maneuvering target in the two-dimensional plane is established,and an expression for estimating the time-to-go for a maneuvering target is ***,an adaptive nonlinear guidance law with a designated impact time is designed based on the adaptive control theory and Lyapunov theory,and the stability of the guidance system is *** that,the proposed guidance law is extended to multiple missiles,enabling multiple missiles to attack a maneuvering target simultaneously or sequentially at specified ***,numerical simulations are conducted to validate the effectiveness of the proposed guidance law.

关键词： Adaptive Designated Time Maneuvering Targets Finite-Time Guidance

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Development of lunar regolith composite and structure via laser-assisted sintering

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Frontiers of mechanical engineering 2022年第1期17卷 178-187页

作者： Hua ZHAO Lu MENG Shaoying LI Jihong ZHU Shangqin YUAN Weihong ZHANG State IJR Center of Aerospace Design and Additive Manufacturing School of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Beijing Institute of Radio Measurement Beijing 100854China Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi'an 710072China Unmanned System Research Institute Northwestern Polytechnical UniversityXi’an 710072China

Aiming at the exploration and resource utilization activities on the Moon,in situ resource utilization and in situ manufacturing are proposed to minimize the dependence on the ground transportation *** this paper,a laser-assisted additive manufacturing process is developed to fabricate lunar regolith composites with PA12/SiO2 mixing *** process parameters and composite material compositions are optimized in an appropriate range through orthogonal experiments to establish the relationship of process–structure–property for lunar regolith *** optimal combination of composite material compositions and process parameters are mixing ratio of 50/50 in volume,laser power of 30 W,scanning speed of 3500 mm/s,and scanning hatch space of 0.2 *** maximum tensile strength of lunar regolith composites reaches 9.248 MPa,and the maximum depth of surface variation is 120.79μm,which indicates poor powder fusion and sintering ***,the mechanical properties of laser-sintered lunar regolith composites are implemented to the topology optimization design of complex *** effectiveness and the feasibility of this laser-assisted process are potentially developed for future lightweight design and manufacturing of the solar panel installed on the lunar rover.

关键词： in situ manufacturing laser-assisted powder fusion process mechanical properties topological structure design

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Differential Private Discrete Noise-Adding Mechanism: Conditions, Properties, and Optimization

Differential Private Discrete Noise-Adding Mechanism: Condit...

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作者： Qin, Shuying He, Jianping Fang, Chongrong Lam, James Shanghai Jiao Tong University Department of Automation Shanghai200240 China Key Laboratory of System Control and Information Processing Ministry of Education of China Beijing100816 China Shanghai Engineering Research Center of Intelligent Control and Management Shanghai200240 China Shenzhen Institute of Research and Innovation Shenzhen518055 China The University of Hong Kong Department of Mechanical Engineering Hong Kong999077 Hong Kong

Differential privacy is a widely used framework for evaluating privacy loss in data anonymization. While the continuous noise-adding mechanism has been extensively studied, there is a dearth of research on discrete random mechanisms for discretely distributed data. This study addresses this gap by examining the primary differential privacy conditions and properties for general discrete random mechanisms, and investigating the trade-off between data privacy and data utility. We establish sufficient and necessary conditions for discrete ϵ-differential privacy and sufficient conditions for discrete (ϵδ)-differential privacy, with closed-form expressions for differential privacy parameters. These conditions can be applied to evaluate the differential privacy properties of discrete noise-adding mechanisms with various types of noise. Moreover, we propose an optimal discrete ϵ-differential private noise-adding mechanism under the utility-maximization framework. Here, the utility is characterized by the similarity of the statistical properties between the mechanism's input and output. Our findings suggest that the optimal class of discrete noise probability distributions in the mechanism is staircase-shaped. © 1991-2012 IEEE.

关键词： Probability distributions

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High-resolution beamforming technology based on entropy dividing sub-array 2

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2nd China International SAR Symposium, CISS 2021

作者： Wang, Ping Tang, Jiwei Ye, Zhou Luo, Jing Zhao, Chenfan Qin, Yi Shanghai Aerospace Electronic Technology Institute Radar Research Room Shanghai China Shanghai Electro-Mechanical Engineering Institute Guidance System Design Shanghai China

ISBN: (纸本)9787000000001

The use of sub-array processing method for large arrays can achieve better processing performance at a small cost. This paper proposes a high-resolution beamforming technique based on entropy dividing sub-arrays for uniform linear arrays. By establishing the entropy model, the effects of sub-array division technology and sub-array unit directivity on the output performance of the array are comprehensively *** performance of sub-array division technology on interference and clutter suppression is simulated and analyzed, and the mathematical solution method of optimal sub-array division is explored. The method is extended to the design of composite multi-band arrays to optimize the parasitic grating lobes caused by missing cells, providing theoretical support and engineering implementable algorithms for the development of large-scale array radars. Finally, the validity and feasibility of the proposed model are verified by experimental data. © 2021 SISE.

关键词： Entropy

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Data-driven modeling fast-slow coupling delayed dynamics using noisy data and sparse enhancement 5

Data-driven modeling fast-slow coupling delayed dynamics usi...

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5th International Conference on Industrial Artificial Intelligence, IAI 2023

作者： Tang, Huifang Wu, Yuqiang Dong, Yingming Cheng, Cheng Li, Xiuting Huazhong Agricultural University College of Science Wuhan China Yunnan Mechanical Research and Design Institute of Machinery Research Institute Group Yunnan Key Laboratory of Mechatronics Applied Technology Yunnan China Ministry of Education of China Huazhong University of Science and Technology Autonomous Intelligent Unmanned System Engineering Research Center Wuhan430074 China Huazhong University of Science and Techonology School of Artificial Intelligence and Automation Wuhan430074 China

ISBN: (纸本)9798350325294

In this work, we focus on fast-slow delayed dynamical systems, which are usually described by coupled delayed differential equations with two-time scales. The purpose of this article is to propose a data-driven discovery method to identify the fast-slow delayed differential equations from noisy measurements. The proposed method blends delay dictionary-based sparse identification of nonlinear dynamics (SINDy) framework and a fixed interval sampling strategy. Specifically, we leverage the SINDy methodology to describe the fast-slow delayed differential equations by a few active terms of a large dictionary containing the delay terms and many candidate nonlinear basis functions. To identify the active terms and the corresponding coefficients, a sequential thresholded re-weighted 2 least squares algorithm is used to solve the resulting sparse regression problem to enhance the sparsity. Once a sparse model with fixed delay is selected, the proposed method further estimates the delayed time by calculating the reconstruction error from the sparse model until the one that makes the reconstruction error minimum. We verify the effectiveness of the proposed method with several classical fast-slow coupling delayed systems. The experimental results show that the proposed method can well automate the fast-slow delayed differential equations from noisy data and the delayed terms also can be detected accurately. © 2023 IEEE.

关键词： Dynamical systems

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Analysis of multi-field cavitation structure and dynamic mode decomposition based on a separated venturi cavitation generator

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European Journal of Mechanics, B/Fluids 2025年 113卷

作者： Wang, Xiaoyu Wang, Tian Ma, Junqi Sun, Qiang Lv, WanYu School of Mechanical Engineering and Automation Northeastern University Shenyang110819 China Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of Education Northeastern University Shenyang110819 China AECC Shenyang Engine Research Institute Shenyang110015 China

Cavitation is generated due to the reduction of fluid pressure, which will cause instability and erosion inside the pipeline, valve or pump etc. In this paper, based on the improved venturi cavitation generator, the cavitation under several different flow conditions is studied, and a high-speed camera is used to capture the dynamic process of cavitation at the venturi throat. The flow field simulation data have been analysed using the dynamic mode decomposition method, and the coherent structures of sheet cavitation, transition zone cavitation, and cloud cavitation and their displacements with cycle time have been investigated. The periodic variation of cavitation is analysed using a combination of experimental and numerical simulations, and the state of cavitation in the flow field is investigated in detail using data-driven tools. The results show that periodic changes in the cavitation structure can be observed intuitively through the improved venturi generator and agrees well with the results of simulation. Cavitation intensity is continuously enhanced with the increase of inlet velocity. At flow velocity of 4.68 m/s, the cavitation is manifested as a piecewise cavitation that can only be observed at the throat position, since then the length of the cavitation cloud continues to increase, finally the detachment of a bubble cloud and localized vortex cavitation are observed at velocity of 6.08 m/s. The frequency and growth characteristics of individual flow modes can be accurately captured using the dynamic modal decomposition of the flow field. © 2025

关键词： High speed cameras

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Dynamic Stiffness Analysis and Parameter Optimization of Digital Electro-Hydraulic Actuator 9

Dynamic Stiffness Analysis and Parameter Optimization of Dig...

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9th International Conference on Fluid Power and Mechatronics, FPM 2023

作者： Zhao, Tian-Yu Wu, Shuai Li, Wen-Ding Li, Ren-Jie Wang, Yi Song, Bing Fu, Jun-Yong Jiao, Zong-Xia School of Automation Science and Electrical Engineering Beihang University Beijing China Research Institute for Frontier Science Beihang University Beijing China Ningbo Institute of Technology Beihang University Ningbo China Shanghai Aerospace Control Technology Institute Shanghai China Shanghai Servo-system Engineering Research Center Shanghai China Beihang University Key Laboratory of Advanced Airborne Systems Beijing China Beihang University Science and Technology on Aircraft Control Laboratory Beijing China Tianmushan Laboratory Hangzhou China

ISBN: (数字)9798350304947

ISBN: (纸本)9798350304947

In this paper, the dynamic stiffness characteristics of digital electro-hydraulic actuator are analyzed, and the influence of the introduction of digital valve on the electro-hydraulic actuator is studied. Based on the actual working conditions and requirements of digital electro-hydraulic actuator, the dynamic stiffness models of digital electro-hydraulic actuator and servo valve controlled electro-hydraulic actuator are established respectively. Two testing methods were used to complete closed-loop dynamic stiffness simulation, and the digital valve control system and the servo valve control system are compared and analyzed. By changing different system parameters, the sensitivity analysis of dynamic stiffness parameters of digital electro-hydraulic actuator is realized. Finally, the optimization of system control parameters is realized, and the optimization direction of the system parameters of the digital electro-hydraulic actuator is provided. © 2023 IEEE.

关键词： Stiffness

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Design and Implementation of Avionic Autonomous Management system for Deep Space Exploration

Design and Implementation of Avionic Autonomous Management S...

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International Symposium on Autonomous systems (ISAS)

作者： ChaoJi Chen YaoBao Yin Jiang Yang Dong Han Lin Tian Hao Zeng XinXin Yu School of Mechanical Engineering of Tongji University Shanghai China Beijing Institute of Spacecraft System Engineering Beijing China Shandong Aerospace Electronics Technology Research Institute Yantai China Beijing Institute of Control Engineering Beijing China

Autonomous management technology is an important means to ensure the long-term safety and autonomous operation of deep space exploration spacecraft on orbit. The development of autonomous management technology of some typical foreign spacecrafts is firstly summarized in this paper. And secondly, based on analyzing the needs of autonomous management of deep space exploration spacecraft, the design and management strategy of autonomous management system are proposed. Then the system architecture and engineering implementation of corresponding avionic autonomous management system are given, by taking the trial new-generation manned spaceship as an example. The results of the on-orbit operation demonstrated that the spaceship could realize functions of autonomous orbit control, autonomous management of flight state, autonomous health management of critical equipment, autonomous disposal of modules separation and autonomous control of reentry in case of non-ground intervention, which ensured the safety of spaceship to the greatest extent and effectively improved its reliability of autonomous operation.

关键词：

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Permanent Magnet Shape Optimization Method for PMSM Air Gap Flux Density Harmonics Reduction

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CES Transactions on Electrical Machines and systems 2021年第4期5卷 284-290页

作者： Chengsi Liu Yongxiang Xu Jibin Zou Guodong Yu Liang Zhuo School of Electrical Engineering and Automation of HIT Department of Electrical Engineering Harbin Institute of Technology the State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin Institute of Technology and National Engineering Research Center for Small and Special Precision Motors Guizhou Aerospace Linquan Motor Co.Ltd

This paper proposed a permanent magnet optimization method to suppress the air gap flux density harmonic of permanent magnet synchronous motor(PMSM).The method corrected the effective air gap length of the motor,calculated the magnetization length of the permanent in the case of parallel magnetization,and took the influence of the permanent magnet relative permeability into *** on these works,for a given sinusoidal air gap flux density waveform,the corresponding structural parameters can be calculated,so as to achieve the optimization of the permanent *** using this method to optimize the shape of the magnet,the fundamental wave of the air gap flux density can be retained to the greatest extent,so as to eliminate harmonics and maintain the output capacity at the same *** feasibility and accuracy of the method have been verified by finite element analysis(FEA)and prototype machine *** method is simple and time-saving,and has a satisfactory accuracy,which provides a reference method for permanent magnet optimization of PMSM.

关键词： Permanent magnet synchronous motor(PMSM) analytical method finite element analysis(FEA) magnet shape optimization.

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A Modular End Effector with Active Rolling Fingertip for Picking Cloth-Like Objects 19

A Modular End Effector with Active Rolling Fingertip for Pic...

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19th IEEE International Conference on automation Science and engineering, CASE 2023

作者： Zhang, Kun Yang, Yuanhang Chen, Zhiming Chen, Hua Wang, Michael Yu Zhang, Wei Robotics Institute Hong Kong University of Science and Technology Clear Water Bay Hong Kong School of System Design and Intelligent Manufacturing Southern University of Science and Technology Shenzhen China Hkust Shenzhen-Hong Kong Collaborative Innovation Research Institute Futian Shenzhen China Monash University Department of Mechanical & Aerospace Engineering ClaytonVIC3800 Australia

ISBN: (纸本)9798350320695

Cloth-like items are ubiquitous in both daily life and industrial production, but their softness makes them difficult to manipulate. This paper focuses on solving the problem of automatic manipulation especially in the scenario of flat surface by introducing a novel end-effector mechanism. The gripper utilizes a modular design concept, enabling it to be reconstructed with a varying number of fingers based on specific requirements. One of the fingers has an active rolling fingertip that rolls up the object from the table to create wrinkles, for easier grasping. Additionally, there are fingertips with revolute joints that enable fine-tuning of the grasp configuration to fix the objects. To test the effectiveness of the mechanism, we manufactured a real gripper device and mounted it on a collaborative robotic arm for grasping tests. Experiments were conducted on six kinds of cloth-like objects with different materials, grasping them from above. The experimental results show that the gripper with this mechanism configuration performs well in this scenario. © 2023 IEEE.

关键词： Grippers

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