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arXiv 2024年

作者： Jiang, Hao Lu, Zhiming Wang, Bofu Meng, Xiaohui Shen, Jie Chong, Kai Leong Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering Science Shanghai University Shanghai200072 China Shanghai Institute of Aircraft Mechanics and Control Zhangwu Road Shanghai200092 China Guangdong Provincial Key Laboratory of Turbulence Research and Applications Center for Complex Flows and Soft Matter Research Department of Mechanics and Aerospace Engineering Southern University of Science and Technology Shenzhen518055 China

This study investigates the spatial distribution of inertial particles in turbulent Taylor-Couette flow. Direct numerical simulations are performed using a one-way coupled Eulerian-Lagrangian approach, with a fixed inner wall Reynolds number of 2500 for the carrier flow, while the particle Stokes number varies from 0.034 to 1 for the dispersed phase. We first examine the issue of preferential concentration of particles near the outer wall region. Employing two-dimensional (2D) Voronoï analysis, we observe a pronounced particle clustering with increasing St, particularly evident in regions of low fluid velocity. Additionally, we investigate the concentration balance equation, inspired by the work of Johnson et al. (2020), to examine particle radial distribution. We discern the predominant sources of influence, namely biased sampling, turbophoresis, and centrifugal effects. Across all cases, centrifugal force emerges as the primary driver, causing particle migration towards the outer wall. Biased sampling predominantly affects smaller inertial particles, driving them towards the inner wall due to sampling within Taylor rolls with inward radial velocity. Conversely, turbophoresis primarily impacts larger inertial particles, inducing migration towards both walls where turbulent intensity is weaker compared to the bulk. With the revealed physics, our work provides a basis for predicting and controlling particle movement and distribution in industrial applications. © 2024, CC BY.

关键词： Spatial distribution

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Impact Angle control Guidance for a Moving Target with General Field-of-View Constraints

Impact Angle Control Guidance for a Moving Target with Gener...

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Chinese control Conference (CCC)

作者： Xiangyu Tang Jianglong Yu Siting Peng Xiwang Dong Qingdong Li Zhang Ren School of Automation Science and Electrical Engineering Science and Technology on Aircraft Control Laboratory Beihang University Beijing P. R. China Beijing Electro-Mechanical Engineering Institute Beijing P. R. China Institute of Artificial Intelligence Beihang University Beijing P. R. China

This paper studies the impact angle control guidance problem with general field-of-view (FOV) constraints for a moving target. Firstly, the control Lyapunov function (CLF) is constructed based on the state-dependent Riccati equation (SDRE) technique, and a nominal controller is designed to intercept the moving target at the desired impact angle without FOV constraints. The control barrier functions (CBFs) are designed according to the FOV constraints. Secondly, the CLF that guarantees stability is combined with the CBFs that guarantee forward invariance of the constraint sets. The minimum modification framework is used to numerically solve the guidance command through quadratic programming to ensure that the look angle of the missile always remains within the constraint interval during the interception process. Finally, the effectiveness of the proposed guidance law is verified by numerical examples.

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Adaptive terminal sliding mode control for flexible air-breathing hypersonic vehicle

Adaptive terminal sliding mode control for flexible air-brea...

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AIAA science and technology Forum and Exposition, AIAA SciTech Forum 2021

作者： Qin, Decong Chen, Haibing Lin, Wei Tang, Peng Ma, Tielin Xu, Cheng School of Transportation Science and Engineering Beihang University Beijing China Aircraft/Engine Integrated System Safety Beijing Key Laboratory Beijing China Beijing System Design Institute of the Electro-mechanic Engineering Beijing China Institute of Unmanned System Beihang University Beijing China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing China

ISBN: (纸本)9781624106095

Flexible air-breathing hypersonic vehicles show significant and complex aerodynamic, scramjet propulsion system, flight dynamic and elastic coupling characteristics, which usually are highly nonlinear. These result in huge uncertainties, parameter perturbation and internal disturbance, which can no longer be ignored, and therefore, extreme difficulties for flight control design. A unique parameter adaptive non-singular terminal sliding mode method is proposed for longitudinal control law design of a flexible coupling air-breathing hypersonic vehicle. This method uses adaptive reaching law gain instead of additional adaptive compensation term to handle the uncertainty to improve robustness. The stability of the close loop system is proved via a Lyapunov way. The longitudinal tracking control law for velocity and angle of attack is designed based on a rigid dynamic model of a flexible air-breathing hypersonic vehicle. A strong coupling model of the same vehicle, considering aerodynamic-scramjet engine-flight dynamic-elastic couplings, is established as the verification platform of control law designed. Simulation results obtained based on the coupling model demonstrate that the control law designed has good performance and acceptable robustness. © 2021, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Hypersonic vehicles

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Torque Analysis of Interior Permanent-Magnet Synchronous Motor with Different Rotor Structure Under Overload Condition

Torque Analysis of Interior Permanent-Magnet Synchronous Mot...

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International Conference on Electrical Machines and Systems (ICEMS)

作者： Chuliang Zheng Hao Qian Yaoxing Shang Zhiyong Wu Hong Guo School of Automation Science and Electrical Engineering Beihang University Beijing China Science and Technology on Aircraft Control Laboratory Beihang University Beijing China Institute of Unmanned Systems Beihang University Beijing China Ningbo Institute of Techonlogy Ningbo China

ISBN: (数字)9781665493024

ISBN: (纸本)9781665493031

The torque overload capability of permanent magnet synchronous motor(PMSM) is very important in transportation applications, which means instantaneous acceleration ability. In the interior PMSMs, the reluctance torque is generated due to the asymmetry of the magnetic circuit, which contributes to the torque overload capacity. In this paper, finite element models(FEMs) of PMSMs with different rotor structures are established to study the torque overload capability. Frozen permeability method is used to analyze the distribution change of rotor permeability under different operating conditions. The torque overload capabilities of different rotor structure are compared. The interior rotor type suitable for overload condition is obtained.

关键词： Resistance Torque Rotors Transportation Synchronous motors Permanent magnets Permeability

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Lines cluster approaching mode control for air-breathing hypersonic vehicle under disturbances and uncertainties

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International Journal of Modeling, Simulation, and Scientific Computing 2020年第1期11卷 152-175页

作者： Fei Ma Yunjie Wu Xiaocen Liu Xiaodong Liu State Key Laboratory of Virtual Reality Technology and Systems Beihang University Beijing 100191P.R.China School of Automation Science and Electrical Engineering Beihang University Beijing 100191P.R.China Science and Technology on Aircraft Control Laboratory Beijing 100191 P.R.China Beijing Aerospace Automatic Control Institute Beijing 100854 P.R.China

This paper investigates the velocity and altitude tracking control problem for airbreathing hypersonic vehicle(AHV)in the presence of external disturbances and parameter uncertainties.A composite controller containing improved lines cluster approaching mode control(LCAMC)and nonlinear disturbance observer(NDO)is developed to guarantee the tracking errors converge to zero and enhance the robustness of control ***,considering the multiple uncertain parameters,a genetic algorithm(GA)based Pareto uncertainty estimation is employed to predict the parameter uncertainties of the AHV ***,the mathematical proofs of proposed method are analyzed by utilizing Lyapunov *** results demonstrate the effective tracking performance,excellent disturbance estimation and uncertainty estimation ability of the composite method.

关键词： Air-breathing hypersonic vehicle tracking control lines cluster approaching mode control nonlinear disturbance observer Pareto uncertainty estimation

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Event-Trigger-Based Finite-Time Privacy-Preserving Consensus Convergence for Networked Agents System

SSRN

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SSRN 2022年

作者： Yue, Jiangfeng Shi, Mengji Li, Weihao Shi, Lei Lin, Boxian Qin, Kaiyu School of Aeronautics and Astronautics University of Electronic Science and Technology of China Chengdu611731 China Aircraft Swarm Intelligent Sensing and Cooperative Control Key Laboratory of Sichuan Province Chengdu611731 China School of Automation Engineering University of Electronic Science and Technology of China Chengdu611731 China

Privacy-preserving has been crucial techniques of distributed networked agents including distributed resource management. distributed scheduling and optimization. Considering not only privacy-preserving but also bandwidth constraints and convergence performance of distributed networked agents, comprehensively, this paper proposes an original event-triggered-based finite-time privacy-preserving consensus scheme to resolve these three difficulties. Firstly, by adopting the output mapping function for privacy mask, the initial true state of each agent is kept indecipherable for honest-but-curious agents and other malicious eavesdropping attackers. Then, considering the limited communication bandwidth and channels, we employ a distributed event-triggered strategy and deduce the event-triggered condition for consensus control, which effectively reduces the excessive consumption of communication and computation resources. In terms of the convergence performance on networked agents, finite-time stability theory is introduced to make the system reach consensus in finite time and obtain a settling time related to the initial state. Compared with the existing literature, this paper systematically synthesizes multiple factors for distributed networked agents and provides convergence analysis and privacy analysis in detail. Finally, the effectiveness of the finite-time privacy-preserving protocol based on event-triggered strategy is demonstrated by numerical simulation examples. © 2022, The Authors. All rights reserved.

关键词： System stability

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High Torque Density Electrical Machine with Less Rare Earth Permanent Magnet

High Torque Density Electrical Machine with Less Rare Earth ...

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IEEE Conference on Industrial Electronics and Applications (ICIEA)

作者： Hang Su Liang Yan Lu Zhang Xiaocheng Wei Ziwei Dong Zijian Jin School of Automation Science and Electrical Engineering Bei Hang University Bei Jing China School of Automation Science and Electrical Engineering Science Beihang University Ningbo China Technology on Aircraft Control Laboratory Bei Hang University Bei Jing China Ningbo Institute of Technology Beihang University Ningbo China

ISBN: (纸本)9781665409858

The All-Electric-aircraft and spacecraft is seeking for high torque density electrical machine to achieve high torque output with lower mass to get higher capability of loading and reduce the cost. The rare earth permanent magnet cannot stand the overheating temperature in outer space thus has the risk of demagnetization causing the space devices out of work. This paper proposes a new magnet topology structure in electrical machine. Compared with other traditional permanent magnet topology structures, it produces a higher magnetic flux density and torque value and decreases the mass of machine, which confirms the proposed magnet topology effectivity in enhance torque density (Nm/kg).

关键词： Space vehicles Magnetic flux Magnetic flux density Torque Costs Permanent magnets Topology

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Distributed Malicious Maneuvering Target Tracking Algorithm With Finite-Time Fusion Analysis

Distributed Malicious Maneuvering Target Tracking Algorithm ...

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Chinese control Conference (CCC)

作者： Zheng Zhang Dong Guo Hongwei Zheng Hong Wang Qingdong Li Xiwang Dong Zhang Ren Science and Technology on Aircraft Control Laboratory School of Automation Science and Electrical Engineering Beihang University Beijing P.R. China China Academic of Launch Vehicle Technology Beijing P.R. china Beijing Academy of Blockchain and Edge Computing Beijing P.R. china Beijing Institute of Control Engineering Beijing P.R. China Institute of Artificial Intelligence Beihang University Beijing P.R. China

This paper proposes a distributed tracking framework for high-maneuvering and malicious maneuvering target based on the sensor network. Considering some of sensors in the network can only observe partial system output, the collective observability is guaranteed. Based on the collective observability, the distributed target tracking algorithm is designed by local filter phase and consensus fusion phase. In local filter phase, the local estimate results can be obtained by each sensor node. Based on the target kinematic and sensor observation equations, the Kalman-like estimation algorithm is proposed to obtain the local estimate results. In most of the exist distributed state estimation (DSE) algorithms, the excellent target tracking performance is based on the assumption that the fusion times is infinity in consensus fusion phase. In practical application, however, the consensus fusion phase should be completed during two sampling instants. Besides, based on the finite-time stability theory, the error covariance matrix is processed as the solution of discrete-time algebraic Riccati equation (DARE). Then the stability of the proposed algorithm with finite-time consensus fusion is analyzed. Finally, a numerical example for tracking maneuvering target is given to validate the effectiveness.

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In-Depth Insight into the Inhibition Mechanism in Iron-Based Composites with Bifunction of Anti-Corrosion and Electromagnetic Wave Absorption Based on Experiments and Theoretical Calculations

SSRN

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SSRN 2024年

作者： Jiang, Xianyu Xie, Jianliang Yin, Liangjun Peng, Jian Li, Jianxiao Jiang, Xian yu Zhang, Min Deng, Longjiang Jing, Zhi Qin, Huanyu Zhang, Linbo Zhang, Peng Yuan, Le National Engineering Research Center of Electromagnetic Radiation Control Materials Key Laboratory of Multi-spectral Absorbing Materials and Structures of Ministry of Education University of Electronic Science and Technology of China 2006 Xiyuan Road Chengdu611731 China Shenyang Aircraft Design and Research Institute Aviation Industry Corporation of China Ltd Shenyang110034 China School of Materials Science and Engineering Xihua University Sichuan Chengdu610039 China

The design of anti-corrosive magnetic metal microwave-absorbing materials is crucial for enhancing the environmental compatibility and service life of military objectives in practical applications. Herein, CI@BTSA@OTMS composites were synthesized using an improved sol-gel method with 2-benzothiazolylthio-succinic acid (BTSA) and trimethoxy (octadecyl) silane (OTMS) as precursor materials. The corrosion resistance mechanisms were investigated in both experimental research and theoretical calculations. Electrochemical experimental results affirmed that the CI@BTSA@OTMS composites exhibited exceptional anti-corrosion with the corrosion potential (Ecorr) shifted positively to 0.05 V, the corrosion current (Icorr) exhibited a low level, measuring only 1.1 × 10−7 A/ cm−2, and the protection efficiency attained 99.91%. The CI@BTSA@OTMS composites exhibited a higher non-wetting property with a contact angle of 138.9°. After 480 hours of exposure in a natural salt spray test, the composites still retained relatively intact morphological and compositional characteristics. These results can be attributed to the effective inhibition of corrosive species' proximity due to the spatial isolation and barrier effects, preventing the formation of an electrochemical corrosion circuit. Moreover, simulations and calculations are employed for revealing the diffusion and inhibition mechanisms of corrosive media. For electromagnetic performance, the introduction of organic layer BTSA@OTMS contributed to improve impedance matching in magnetic metal microwave absorbers. © 2024, The Authors. All rights reserved.

关键词： Corrosion resistance

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Distributed Prescribed-Time Formation Tracking for General Linear Multiagent Systems

Distributed Prescribed-Time Formation Tracking for General L...

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International Conference on control and Automation (ICCA)

作者： Zhexin Shi Yikun Yang Jianglong Yu Xiwang Dong Qingdong Li Zhang Ren Science and Technology on Aircraft Control Laboratory School of Automation Science and Electrical Engineering Beihang University Beijing P. R. China Shenyuan Honors College Beihang University Beijing P. R. China Institute of Artificial Intelligence Beihang University Beijing P. R. China Institute of Unmanned System Beihang University Beijing P. R. China

ISBN: (数字)9798350354409

ISBN: (纸本)9798350354416

This paper studies prescribed-time formation tracking problems for general linear multiagent systems with a leader of unknown input. First, by introducing a time-varying parametric Lyapunov equation, a distributed prescribed-time formation tracking protocol is proposed for each follower to accomplish an expected formation within a prescribed time, and simultaneously follow the leader's state trajectory. Then, adaptive gains are developed to achieve formation tracking in a fully distributed manner and to compensate for the leader's unknown input. Furthermore, the prescribed-time convergence of the formation tracking error is analyzed using Lyapunov theories. Finally, the effectiveness of theoretical results is validated through a simulation example.

关键词： Protocols Upper bound Automation Mathematical models Trajectory Topology Multi-agent systems

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