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Vibration of Composite High Aspect Ratio Thin-Walled Wing-Aileron Plate Coupling Structures With Hinged Connection: Analytical and Experimental Investigations

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International Journal of Structural Stability and Dynamics 2025年

作者： Song, Xu-Yuan Zhang, He Zhao, Wen-Rui Qin, Zheng-Qi Zhang, Ye-Wei College of Aerospace Engineering Shenyang Aerospace University Shenyang110136 China Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of Education Northeastern University Shenyang110819 China

This literature contributed to scientific experimental and theoretical investigations to gain insight into the coupling vibration of composite high aspect ratio thin-walled wing-aileron plate structures with a hinged connection of aircraft. In order to facilitate the analysis and design process, a composite plate combining structures with hinged connection (CPSHC), which were connected by a set of hinged structures, was considered as the mechanical model of the composite high-aspect ratio thin-walled wing-aileron plate structures. The kinetic energy, potential energy and hygrothermal potential energy are derived via the Kirchhoff thin plate hypothesis, and a group of elastic springs are introduced to install zones of the plain bearings to simulate dynamic bearing stiffness. The governing equation of motion of the thin-walled wing-aileron plate coupling structures can be derived in the frame of the Rayleigh–Ritz method according to adopting a range of modified orthogonal polynomials as the displacement admissible functions. The piecewise-linear nonlinear stiffness analytical model of the hinged structures is established via the experiment. To validate the correctness and accuracy of the method, a series of experiments and finite element simulations were carried out. Subsequently, the distinctive vibration characteristics of the CPSHC under varying hinge stiffness, different lengths of the hinge structure, diverse installation positions of the hinge structure, and distinct rotation angles were delved into in depth. Additionally, the influence of thermal loads on the vibration of the CPSHC is especially prominent within a particular temperature range, mainly being affected by the inherent characteristics of the material. © 2026 World Scientific Publishing Company.

关键词： Piecewise linear techniques

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Data-Driven Learning and control with Event-Triggered Measurements

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IEEE Transactions on Automatic control 2025年

作者： Feng, Shilun Shi, Dawei Chen, Tongwen Shi, Ling Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex Systems MIIT Key Laboratory of Servo Motion System Drive and Control School of Automation Beijing100081 China University of Alberta Department of Electrical and Computer Engineering EdmontonABT6G 1H9 Canada Hong Kong University of Science and Technology Department of Electronic and Computer Engineering Clear Water Bay Kowloon Hong Kong

Event-triggered control has attracted considerable attention for its effectiveness in resource-restricted applications. To make event-triggered control as an end-to-end solution, a key issue is how to effectively learn unknown system dynamics from event-triggered measurements and consequently, develop a learning-based event-triggered controller. Existing works learn system dynamics based on periodic time-triggered measurements, and it is yet to know how to learn a controller with performance guarantee based on event-triggered measurements. To address this issue, we consider the problem of learning an event-triggered state feedback controller for an unknown linear system based on event-triggered state measurements in this work. In particular, we first analyze the event-triggered measurements within a set-membership framework. We prove that the estimation error belongs to a bounded ellipsoid determined by the historical measurements and the event-triggering condition. Subsequently, we demonstrate that all admissible systems compatible with the collected data samples can be explicitly represented in the form of quadratic matrix inequalities using the state estimates. With the acquired set of admissible systems, a co-design problem for the data-driven controller and event-triggering condition is solved using the linear matrix inequality technique, with guaranteed closed-loop stability and L2-gain performance. Finally, numerical examples and comparisons are provided to illustrate the effectiveness of the proposed event-triggered learning and control approach. © 1963-2012 IEEE.

关键词： Networked control systems

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Negative-pressure soft pneumatic actuators enabled by asymmetrically distributed bending units

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Extreme Mechanics Letters 2025年 77卷

作者： Fu, Zeyu Chen, Tianyu Zou, Haoran Zhu, Zhiwei Deng, Zichen Wang, Yifan School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi'an710072 China MIIT Key Laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical University Xi'an710072 China School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore 639798 Singapore State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China

Soft pneumatic actuators are highly flexible and can adapt to complex environments, attracting significant attention for their ability to operate in settings where rigid actuators cannot. Most existing soft pneumatic actuators are powered by positive pressure, which has the disadvantage of volume increase during operation and risk of exploding under large pressures. In this study, we designed a new type of soft actuator by inducing asymmetric bending deformation throughout a holey structure under negative pressure. Using finite element analysis and a theoretical model, we studied the effects of various geometric parameters on the structure's bending behavior. We found that the displacement of the circle's center from the central axis is a parameter with the most significant impact on the bending behavior of the structure. By designing circular holes with offset from the central axis, the structure can bend toward the offset direction during subsequent bending deformation. Based on this deformation mechanism, we designed a soft gripper that bends upon actuation and effectively picks up objects. We further designed a bi-directional gripper that bends towards both sides and a circular gripper that contracts towards the center upon evacuation to hold objects. These soft grippers’ grasping capabilities are validated by experimental tests. Finally, by arranging the holes in a wavy pattern within the structure, we created a crawling robot that moves forward through cyclic negative pressure actuation. These findings highlight the potential of leveraging bending behaviors in asymmetrically distributed holey structures for the development of negative-pressure driven soft actuators and robots. © 2025 Elsevier Ltd

关键词： Pneumatic actuators

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Aggregation Modeling of system Frequency Response Under Inertia control of Grid-following Direct-drive Wind Turbine

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Dianli Xitong Zidonghua/Automation of Electric Power systems 2025年第10期49卷 39-48页

作者： Jiang, Chao Yang, Dongfeng Guo, Shujia Liu, Xiaojun Zhou, Shuyu Cao, Zhichong Key Laboratory of Modern Power System Simulation and Control & Renewable Energy Technology Ministry of Education Northeast Electric Power University Jilin132012 China School of Automation and Electrical Engineering Zhejiang University of Science and Technology Hangzhou310023 China State Grid Jilin Electric Power Research Institute Changchun130000 China

The inertia control of grid-following direct-drive wind turbines significantly influences the system frequency response pattern afrer disturbances. However, current research has not clearly identified the dominant response link of direct-drive wind turbines in frequency regulation, while the modeling is too complicated to be suitable for frequency characteristic analysis. Therefore, the linearized models under inertia control are derived for two typical types of direct-drive wind turbines according to the aerodynamic equations, generator models, power control link, and control circuit structure. The fast physical process of current control-boost circuit/stator voltage dynamic loop is clearly understood and reasonably ignored. It is revealed that the two types of direct-drive wind turbines have a common frequency response mechanism which can be described as the cascade effect of the speed regulator-wind rotor motion equation. Furthermore, combined with the frequency response model of synchronous unit, the aggregation model of system frequency response under the inertia control of grid-following direct-drive wind turbines is constructed, and the aggregation model is reduced to a second-order model by the balance truncation method for analytical calculation of frequency extremes. The accuracy and applicability of the aggregation model and its reduced-order model are verified by MATLAB/Simulink simulation, and the influence of control parameters and system states on frequency dynamic characteristics and stability margin is analyzed. © 2025 Automation of Electric Power systems Press. All rights reserved.

关键词： Electric power system control

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Dissemination Characteristics and Exposure Risk Assessment of Antibiotic Resistance Genes via Aerosols from Wastewater Treatment Processes

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Water (Switzerland) 2025年第9期17卷 1305-1305页

作者： Ding, Diangang Sun, Jianbin Chi, Mingjia Liu, Lan Ren, Zening Liu, Jianwei Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control Beijing University of Civil Engineering and Architecture Beijing100044 China School of Environment and Energy Engineering Beijing University of Civil Engineering and Architecture Beijing100044 China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing210008 China

Wastewater treatment plants (WWTPs) have been confirmed as reservoirs of antibiotic resistance genes (ARGs). This study systematically investigated the distribution patterns of ARGs across different treatment units in municipal WWTPs, along with the environmental drivers, dissemination characteristics, and exposure risks of aerosol-borne ARGs in aerated tank environments. The results revealed a high compositional similarity in aerosol-borne ARGs across the sampling sites, with multidrug ARGs predominating at an average relative abundance of 52%, followed sequentially by tetracycline (11%), MLS (10%), and glycopeptide resistance genes (7%). The diffusion of aerosol-borne ARGs is significantly influenced by environmental factors including temperature, relative humidity, wind speed, and total suspended particulate (TSP) concentration, with temperature being the most dominant factor affecting the dispersion of ARGs. The atmospheric dispersion model demonstrates that aerosol-borne ARGs decay with increasing downwind distance, showing potential for transport from aeration tanks to locations exceeding 1500 m along the prevailing wind direction. Both within wastewater treatment units and downwind areas, adult males had higher respiratory exposure doses but lower skin contact doses compared to females, with respiratory doses exceeding skin contact by 3–4 orders of magnitude. This study highlights the potential health risks posed by aerosol-borne ARG transmission from WWTP operations. © 2025 by the authors.

关键词： Risk assessment

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Phase-gain Dual-parametric Spectrum Measurement in Chaotic Brillouin Optical Correlation Domain Analysis

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IEEE Sensors Journal 2025年

作者： Chen, Jing Wang, Yahui Ma, Jinglian Huang, Haochen Zhang, Mingjiang Taiyuan University of Technology Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan030024 China Taiyuan University of Technology College of Physics and Optoelectronics Taiyuan China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan030024 China

In this paper, the chaotic Brillouin phase-gain dual-parametric spectrum (BDS) is measured for the first time, which can realize high-accuracy and large-range dynamic strain demodulation in chaotic Brillouin optical correlation domain analysis (CBOCDA). The phase of the chaotic probe wave is measured by a Sagnac interferometer (SI) combined with an optical bandpass filter (OBPF) and a beat frequency locking technique. The Brillouin gain spectrum (BGS), Brillouin phase-shift spectrum (BPS), and BDS are measured in the chaotic BOCDA system through both simulation and experiment, and the feasibility of their demodulation with high-accuracy and large-range dynamic strain is verified. The chaotic BPS exhibits good linearity at the Brillouin frequency shift (BFS) and can be used to demodulate high-accuracy tiny strains. The measurement error of a 1 μΕ strain is only 0.0446 μΕ. The linear range of the chaotic BDS is extended to 150 MHz, and more than 10 mΕ dynamic strain measurements can be enabled by incorporating the slope-assisted method. © 2001-2012 IEEE.

关键词： Ultraviolet spectroscopy

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Deep reinforcement learning-based trajectory planning for double pendulum cranes: Design and experiments

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Mechanical systems and Signal Processing 2025年 234卷

作者： Ding, Weili Zhang, Heng Hua, Changchun Lu, Biao Engineering Research Center of Intelligent Control System and Intelligent Equipment Ministry of Education Laboratory of Intelligent Rehabilitation and Neuromodulation of Hebei Province Institute of Electrical Engineering Yanshan University Qinhuangdao066004 China Institute of Robotics and Automatic Information System College of Artificial Intelligence Nankai University Tianjin300353 China Institute of Intelligence Technology and Robotic Systems Shenzhen Research Institute of Nankai University Shenzhen518083 China

Since cranes usually possess double pendulum dynamics, the mass of the payload often changes and there are frequently lifting/lowering operations simultaneously. Moreover, most crane systems are driven by motors, whose velocities and accelerations are often limited. To solve the above problems, this paper proposes a deep reinforcement learning (DRL) reference trajectory generation method based on virtual–physical joint training. Firstly, a DRL module based on deep deterministic policy gradient (DDPG), along with a double pendulum crane dynamic model and an adaptive controller, are established within the virtual environment for training the reference trajectory. When the reward reaches the threshold, the training is switched to the physical environment to further optimize the reference trajectory, realizing the swing suppression of the hook and the payload. In addition, to satisfy the performance of the drive motors, velocity and acceleration thresholds are set to constrain the performance of the drive motors. Finally, in view of the fact that the operation process of the double pendulum crane is divided into payload transportation and payload loading/unloading, an event-triggering mechanism is designed to switch different control policies in accordance with different operation processes, thus reducing the consumption of computing resources. Through experiments on the actual double pendulum crane and comparison with the existing reference trajectories and input shapers, the superiority of this method is demonstrated. © 2025 Elsevier Ltd

关键词： Model reference adaptive control

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Hydrogel-anchored caffeic acid-copper ions coating: Integrated defensive and offensive strategy for synergistic antifouling

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Chemical engineering Journal 2025年 515卷

作者： Niu, Jingyu Li, Yiming Shen, Yun Yuan, Shideng Wang, Dong Zheng, Peijun Wang, Zhining Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and Engineering Shandong University Qingdao266237 China China Frontiers Science Center for Deep Ocean Multispheres and Earth System/Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China Qingdao266100 China

Marine biofouling poses significant global challenges for maritime activities, resulting in serious economic losses and environmental issues. Biomimetic coatings have drawn extensive attentions due to their environmentally friendly antifouling properties. Herein, an innovative strategy is reported for constructing antifouling coating composed of caffeic acid-copper ions (CA-Cu2+) anchored on a Kevlar hydrogel. The resultant coating achieves good adhesion (1.3 MPa) to various substrates via the bioinspired polymerization of metal-polyphenol networks (MPNs). The hydrophilic nature and synergistic antimicrobial effects enable efficient self-cleaning, anti-protein (100 %), anti-bacterial (100 %), and anti-algae (99.84 %) performance. Strikingly, the coating exhibits superior acid and alkali tolerance, abrasive resistance, and long-term stability over 60 days in real seawater, owing to the hydrogen bonds and coordination interactions between the Kevlar hydrogel and the CA-Cu2+ functional layer. Further research demonstrates that the antifouling performance are realized via the synergistic antifouling models. The hydration layer formed by the synergistic action of the hydrogel and CA effectively prevents the attachment of microorganisms, and the chemodynamic antibacterial mode triggered by Cu2+ can actively kill the microorganisms adhered to the material surface. Importantly, the Cu2+ release profile of the H/PCA-Cu coating meets the environmental requirements. The "defensive" and "offensive" integrated antifouling strategy provides groundbreaking performance for broad-spectrum biofouling control, which greatly desired for marine facilities. Our work not only expands the family of MPNs application in marine antifouling coatings, but also pioneers a rational pathway toward developing long-lasting and environmentally friendly broad-spectrum antifouling coatings. © 2025 Elsevier B.V.

关键词： Antifouling paint

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Distributed Fault-Tolerant Formation Game for Quadrotor UAVs With Hybrid Attacks

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IEEE Transactions on Aerospace and Electronic systems 2025年

作者： Zhang, Rui-Ming Yao, Xiang-Yu Wang, Leimin Park, Ju H. Ge, Ming-Feng China University of Geosciences School of Mechanical Engineering and Electronic Information Wuhan430074 China Ministry of Education Key Laboratory of System Control and Information Processing Shanghai200240 China China University of Geosciences School of Automation Wuhan430074 China Yeungnam University Department of Electrical Engineering Gyeongsan38541 Korea Republic of

This manuscript studies the distributed faulttolerant formation for quadrotor unmanned aerial vehicles (QUAVs) subject to actuator failures and hybrid cyber attacks via a game-theoretical approach. The desired formation, which aligns with optimal self-interests, is achieved by seeking the Nash equilibrium (NE) of the game under a strongly connected directed graph. First, a secure fault-tolerant NE seeking algorithm is presented to handle actuator failures and false data injection (FDI) attacks, with the false data being measured through extended state observers (ESOs). The proposed algorithm is established on pseudo-gradient dynamics, in which a local estimate law is used to anticipate the actions of other QUAVs. Then, an ESOsbased algorithm is developed to mitigate the influence of FDI and denial-of-service (DoS) attacks, guaranteeing that all QUAVs exponentially converge to an adjustable small domain of NE by Lyapunov stability analysis. This work is distinct from existing studies by addressing the practical scenario, where physical failures and hybrid cyber attacks occur simultaneously in the game framework of QUAVs. Eventually, numerical experiments are conducted to demonstrate the efficacy of theoretical findings. © 1965-2011 IEEE.

关键词： Drones

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Point-Plane Better than Point-Point – for Embedding-based USAD 8

Point-Plane Better than Point-Point – for Embedding-based U...

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8th International Conference on Video and Image Processing, ICVIP 2024

作者： Zhao, Zhirong Zhang, Yuanhao Yu, Zujun Zhu, Liqiang Science and-Technology Department Guoneng Shuohuang Railway Development Co Ltd. Cangzhou Cangzhou062350 China Frontiers Science Center for Smart High-Speed Rail System Beijing Jiaotong University Beijing100044 China State Key Laboratory of Advanced Rail Autonomous Operation Beijing Jiaotong University Beijing100044 China School of Mechanical Electronic and Control Engineering Beijing Jiaotong University Beijing100044 China

ISBN: (数字)9781510689244

ISBN: (纸本)9781510689237

As deep neural networks (DNNs) have advanced, high-quality pre-trained models have provided excellent feature extraction methods for embedding-based unsupervised anomaly detection (EUSAD). However, when calculating anomaly scores, common EUSAD models often rely on point-to-point distance computations between test features and reference features. This approach not only fails to fully utilize the carefully integrated reference feature library but may also increase pixel-level false positives due to the incorrect selection of reference points. To address this issue, this paper adopts the least squares method, evaluating anomalies by calculating the distance between test feature points and the reference feature plane. Experimental results demonstrate that this method not only performs well in global image detection but also significantly reduces pixel-level false positives, showing strong performance across many anomaly detection datasets. © 2025 SPIE.

关键词： Pixels

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