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Chinese Automation Congress (CAC)

作者： Xiongjun Wu Jialing Zhou Yuanlong Li Chunfang Chen Kai Li National Defense Key Laboratory of Science and Technology on Electromagnetic Scattering The 802 Institute of Shanghai Academy of Space Flight Technology The Eighth Academy of China Aerospace Science and Technology Corporation Shanghai China Key Laboratory of System Control and Information Processing Ministry of Education of China Shanghai Jiao Tong University Shanghai China School of Automation Nanjing University Science and Technology Nanjing The 802 Institute of Shanghai Academy of Space Flight Shanghai School of Automation Science and Electrical Engineering Beihang University Beijing

ISBN: (纸本)9781665426480

The constructive semi-global differential game concept is introduced into the multi-agent’s cooperative controller designing of typical autonomous unmanned systems subject to controller input constraint as well as the collision avoidance requirements simultaneously. The problem of driving each agent which is assume to subject to input constraint nonlinearity from the initial position to a desired one and at the same time avoiding collisions (referring to both static obstacles and other agents) is modeled and transformed into multi-agent’s collision avoidance problem. In view of the requirement that different agents working together might possibly have individual but conflicting purpose (such as in the multi-missile cooperative detection requiring slowly and continuing actions vs fast formation control scenario, and multi-agents’ fast arriving vs avoiding different kinds of obstacles). The differential game theory provided a mechanism or framework for investigating different kinds of problems in which several players seek to achieve individual purposes or goals, which might be competing rather than cooperation. In view of the input constraints, the problem is reduced as a semi-global differential game. Conditions are established to guarantee input constraints are satisfied, and mainly by using the Hamilton-Jacobi-Isaacs (HJI for short) PDIs and as well as ε-Nash equilibria. The semi-global property of the states are also guaranteed. It provides a description in terms of the invariant set for the overall differential game system under constraint controller input. Illustrative examples are carried out to verify the effectiveness of the method, and also the feasibility of the suggested control protocols.

关键词： Protocols Automation Design methodology Differential games Games control systems Collision avoidance

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Multi-feature fusion based vision locating method for lunar surface sampling teleoperation

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Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica 2022年第12期43卷

作者： Liu, Chuankai Li, Dongsheng Xie, Jianfeng Lei, Junxiong Yuan, Chunqiang He, Ximing Beijing Aerospace Control Center Beijing100190 China Nation Key Laboratory of Science and Technology on Aerospace Flight Dynamics Beijing100190 China School of Electrical Engineering and Automation Jiangxi University of Science and Technology Ganzhou341000 China

In lunar surface sampling by Chang'e 5, it is difficult to use the slender and flexible manipulator to achieve precise operations, such as digging, putting the sample into the pot, pot grasping and assembly, etc. In this paper, a vision system, consisting of static cameras installed on the lander and dynamic cameras mounted on the manipulator, is developed to get images and relative positions of the end-effector relative to the targets, so as to guide precise operations. We propose a novel positioning method by combining two kinds of features observed in multiple cameras, the circular objects and drones, and build a unified framework for calculating the relative poses between the end-effector and the targets in different operations. The influences of the manipulator error on the convergence of visual positioning are analysed, and several applications with combinations of different features and cameras are realized for operations of digging, sample putting, etc. Experimental validation and analysis show that the accuracy of binocular ellipses positioning in digging is better than 2 cm, and the accuracy of positioning with circular objects and drones in sample putting is better than 2 mm. The results meet the requirements of various operations, and the method proposed successfully supported implementation of the Chang'e 5 lunar surface sampling and packaging mission. © 2022 AAAS Press of Chinese Society of Aeronautics and Astronautics. All rights reserved.

关键词： End effectors

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A vision-based navigation method for eVTOL final approach in urban air mobility(UAM)

A vision-based navigation method for eVTOL final approach in...

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Conference on Vehicle control and Intelligence (CVCI)

作者： Siyuan Ye Zeyu Wan Long Zeng Chenglong Li Yu Zhang College of Aeronautical Engineering Civil Aviation Flight University of China Guanghan China College of Control Science and Engineering Zhejiang University Hangzhou China College of Air Traffic Management Civil Aviation Flight University of China Guanghan China Civil Aviation Flight University of China Guanghan China State Key Laboratory of Industrial Control Technology College of Control Science and Engineering Zhejiang University Hangzhou China

ISBN: (数字)9781728184975

ISBN: (纸本)9781728184982

Urban air mobility(UAM) is an emerging way of air transportation by using self-pilot electric vertical takeoff and landing (eVTOL) vehicles to transport people and cargo in an urban area. The final approach is the critical stage in the operation. Accurate location information and vertical height guidance are needed in this stage. In addition to the common GNSS/INS integrated navigation system, this work proposes an independent vision-based method to provide redundant location information in the final approach for eVTOL vehicles. The simulation results show that the positioning accuracy of the visual method is within 1.5 meters when the vehicles are no more than 25 meters away from the reference place.

关键词： Meters Visualization Navigation Simulation Urban areas Cameras Robustness

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A Novel Methodology for Calculating Crack Opening Stress under Tension-Compression Cyclic Load

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Advances in Materials science and Engineering 2021年第1期2021卷

作者： Zhang, Lin Wei, Xiaohui Key Lab. of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and Astronautics Jiangsu Nanjing210016 China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics Jiangsu Nanjing210016 China

Crack closure model has been used in several applications on the prediction of fatigue crack growth life, with expression of crack opening stress often serving as milestones. A typical difficulty in calculating the crack opening stress is the phenomenon of crack closure caused by the compressive load effect. Compressive load effect, resulting in the change of residual stress status at the unloading stage and the decrease of crack opening stress, is a long-term challenge for predicting fatigue crack growth life. We propose the expression of crack opening stress to predict fatigue crack growth life based on the analysis of compact tensile specimen with elastoplastic element method. It combines the characteristics of material and load to deal with the phenomenon of crack closure and uses stress ratio and normalized maximum applied load variable to construct the expression of crack opening stress. In the study of tensile-compression fatigue crack growth experiments, the proposed expression is proved to improve, by comparative analysis, the predictive ability on the whole range of experiment data. The novel expression is accurate and simple. Consequently, it is conducive to calculate the crack opening stress under tension-compression load. © 2021 Lin Zhang and Xiaohui Wei.

关键词： Crack closure

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Sliding Mode Observation and control for Overhead Cranes with Varying Rope Length

Sliding Mode Observation and Control for Overhead Cranes wit...

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Chinese Automation Congress (CAC)

作者： Xuwei Huan Dan Niu Qi Li Jun Yang Guoyao Liu Xisong Chen Xi Xiao Key Laboratory of Measurement and Control of CSE Ministry of Education Southeast University Nanjing China Loughborough University Loughborough UK Nanjing Sciyon Automation Group Co. Ltd Nanjing China Aviation Key Laboratory of Science and Technology on Aero Electromechanical System Integration Nanjing China

ISBN: (纸本)9781665426480

This paper proposes a state observer and controller based on the second-order sliding mode scheme for under-actuated overhead cranes with load hoisting and lowering. The designed state observer can effectively estimate the uncertainty and unmodeled dynamics of crane systems, and provide appropriate driving force compensations for the sliding mode controller designed by coupling the load swing angle. This guarantees an accurate load positioning and residual swing elimination. Based on the Lyapunov stability criterion, the asymptotic stability of the control system is proved. Several simulations are implemented to verify the effectiveness and robustness of the proposed controller for anti-sway and positioning controls.

关键词： Cranes Uncertainty Force Dynamics Observers Robustness Stability analysis

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Optimization of High-Speed WIG Airfoil with Consideration of Non-ground Effect by a Two-Step Deep Learning Inverse Design Method

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Transactions of Nanjing University of Aeronautics and Astronautics 2025年第1期42卷 56-69页

作者： WANG Chenlu SUN Jianhong ZHENG Daren SUN Zhi ZUO Si LIU Hao LI Pei Key Laboratory of Aircraft Environment Control and Life Support Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China Key Laboratory of Civil Aviation Emergency Science&Technology Civil Aviation Administration of ChinaNanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China

Under complex flight conditions,such as obstacle avoidance and extreme sea state,wing-in-ground(WIG)effect aircraft need to ascend to higher altitudes,resulting in the disappearance of the ground effect.A design of high-speed WIG airfoil considering non-ground effect is carried out by a novel two-step inverse airfoil design method that combines conditional generative adversarial network(CGAN)and artificial neural network(ANN).The CGAN model is employed to generate a variety of airfoil designs that satisfy the desired lift-drag ratios in both ground effect and non-ground effect ***,the ANN model is utilized to forecast aerodynamic parameters of the generated *** results indicate that the CGAN model contributes to a high accuracy rate for airfoil design and enables the creation of novel airfoil ***,it demonstrates high accuracy in predicting aerodynamic parameters of these airfoils due to the ANN *** method eliminates the necessity for numerical simulations and experimental testing through the design procedure,showcasing notable *** analysis of airfoils generated by the CGAN model shows that airfoils exhibiting high lift-drag ratios under both flight conditions typically have cambers of among[0.08c,0.105c],with the positions of maximum camber occurring among[0.35c,0.5c]of the chord length,and the leading-edge radiuses of these airfoils primarily cluster among[0.008c,0.025c]

关键词： conditional generative adversarial network(CGAN) artificial neural network(ANN) airfoil design wing-in-ground(WIG)aircraft ground effect

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Two Degree-of-Freedom Dynamic Theoretical Model on Tile Thermal Protection System

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第1期36卷 139-145页

作者： HUANG Jie YAO Weixing KONG Bin YANG Jiayong WANG Man ZHANG Qingmao Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and Astronautics State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics AVIC Chengdu Aircraft Design and Research Institute

In order to study the dynamic behaviors of the thermal protection system(TPS)and dynamic strength of the strain-isolation-pad(SIP),a two degree-of-freedom dynamic theoretical model is presented under the acoustic excitation and base excitation. The tile and SIP are both considered as the elastic body and simplified as a mass point,a linear spring and a damping element. The theoretical solutions are derived,and the reasonability of theoretical model is verified by comparing the theoretical results with the numerical results. Finally,the influences on the dynamic responses of TPS by the structural damping coefficient of TPS,elasticity modulus and thickness of SIP are *** results show that the material with higher damping,and SIP with thicker size and lower elastic modulus should be considered to reduce the dynamic responses and intensify the security of TPS. The researches provide a theoretical reference for studying the dynamic behaviors of TPS and the dynamic strength of SIP. Besides,the dynamic theoretical model can be used as a quick analysis tool for analyzing the dynamic responses of TPS during the initial design phase.

关键词： thermal protection system dynamic theoretical model acoustic excitation base excitation

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Lithium-Ion Insertion Properties of One-Dimensional Layered Rhenium Phosphide

SSRN

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SSRN 2022年

作者： Zheng, Penglun Sun, Xiaoli Liu, Yaoda Li, Zhifa Liu, Quanyi Zheng, Yun Dai, Zhengfei Civil Aircraft Fire Science and Safety Engineering Key Laboratory of Sichuan Province Civil Aviation Flight University of China Guanghan618307 China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong University Xi’an710049 China Key Laboratory of Optoelectronic Chemical Materials and Devices Ministry of Education School of Optoelectronic Materials & Technology Jianghan University Wuhan430056 China Department of Energy and Power Engineering Tsinghua University Beijing100084 China Beijing Graphene Institute Beijing100095 China Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical Engineering and New Phosphorus Materials The Higher Educational Key Laboratory for Phosphorus Chemical Engineering of Yunnan Province Kunming650500 China

Metal phosphides have aroused great interest among the electrochemical community due to their stunning performance, including good electrical conductivity, high theoretical capacity, and considerable cycling stability. In this work, we synthesized and utilized Re6P13 for the first time as a promising anode material for lithium-ion batteries (LIBs). High-purity Re6P13 needle-like crystals were successfully grown by a chemical vapor transport method. Surface modification of Re6P13 by conductive carbon results in Re6P13@C composite electrode, exhibiting a high specific capacity of 1265 mAh g-1 at 0.1 A g-1. The calculated band structure of Re6P13 reveals a high symmetric point path that is beneficial for achieving high electrical conductivity and good structural flexibility. These features further empower the Re6P13@C composite anodes with good cycling life (775 mAh g−1 at 1 A g−1 after 100 cycles) and rate performance (558 mAh g-1 at 20 A g-1). This work suggests that Re6P13 compounds with the needle-like structure are promising anode materials for LIBs. © 2022, The Authors. All rights reserved.

关键词： Lithium-ion batteries

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Computation of reachable sets based on Hamilton-Jacobi-Bellman equation with running cost function

TechRxiv

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TechRxiv 2021年

作者： Liao, Wei Liang, Taotao Wei, Xiaohui Lai, Jizhou Yin, Qiaozhi Key laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics Nanjing210016 China The Navigation Research Center Nanjing University of Aeronautics and Astronautics Nanjing210016 China

A novel method for computing reachable sets is proposed in this paper. In the proposed method, a Hamilton-Jacobi-Bellman equation with running cost function is numerically solved and the reachable sets of different time horizons are characterized by a family of nonzero level sets of the solution of the Hamilton-Jacobi-Bellman equation. In addition to the classical reachable set, by setting different running cost functions and terminal conditions of the Hamilton-Jacobi-Bellman equation, the proposed method allows to compute more generalized reachable sets, which are referred to as cost-limited reachable sets. In order to overcome the difficulty of solving the Hamilton-Jacobi-Bellman equation caused by the discontinuity of the solution, a method based on recursion and grid interpolation is employed. At the end of this paper, some examples are taken to illustrate the validity and generality of the proposed method. © 2021, CC BY.

关键词： Numerical methods

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Investigation of infrared radiation characteristics of MgO-doped YSZ coatings fabricated via atmospheric plasma spraying

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Infrared Physics & technology 2025年 150卷

作者： Juhang Yin Min Zhang Huazhong Zhang Tong Zhou Yang Xiang Mian Zhong Chao Zhou Xiaoguang Tu Yin Zhang Li Zhang College of Aviation Electronics and Electrical Civil Aviation Flight University of China Guanghan 618307 Sichuan China Shenyang Aircraft Design and Research Institute The Avitation Industry Corporation of China Ltd. Shenyang 110035 China National Engineering Research Center of Electromagnetic Radiation Control Materials Key Laboratory of Multi-spectral Absorbing Materials and Structures of Ministry of Education State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Chengdu 611731 China

Yttrium-stabilized zirconia (YSZ) plays a vital role in infrared stealth technology, owing to its exceptional thermal stability and electrical conductivity. However, its emissivity in the critical 3–5 μm wavelength range remains relatively high, prompting the need for further reductions as aircraft operational temperatures increase. This study investigates the preparation of YSZ coatings doped with magnesium oxide (MgO) using atmospheric plasma spraying (APS) and evaluates the effects of varying MgO concentrations on the microstructure, crystal structure, and infrared emissivity of the coatings. The findings indicate that MgO doping significantly enhances the concentration of oxygen vacancies and promotes grain growth, resulting in a marked reduction in emissivity to 0.55 at 5 mol% MgO. Additionally, high-temperature emissivity assessments demonstrate a continued decrease in emissivity with rising temperature, underscoring the potential of MgO-doped YSZ coatings for advanced stealth applications.

关键词： Doped Emissivity Oxygen vacancy YSZ

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