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Thickness Measurement of Single-Mode Fiber Coating Layer Based on Forward Brillouin Scattering

IEEE Sensors Journal 2025年

作者： Zhang, Yongqi Wang, Tao Liu, Yijia Liu, Li Zhang, Mingjiang Taiyuan University of Technology Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education College of Physics and Optoelectronic Engineering Taiyuan030024 China Taiyuan University of Technology Shanxi Key Laboratory of Precision Measurement Physics College of Physics and Optoelectronic Engineering Taiyuan030024 China

The coating layer is essential for protecting and applying optical fibers. Nowadays, the thickness measurement of the coating layer relies on point measurement schemes such as the side-looking light distribution method and mechanical method. However, there are some problems with the above methods, such as the trade-off between resolution and field of view, the cutting of the measurement position and the long measurement time. To overcome these problems, we propose a new method based on forward Brillouin scattering, which measures the coating layer thickness of single-mode fibers. The physical properties of the transverse acoustic field involved in forward Brillouin scattering make it possible to measure the thickness of the fiber coating. The corresponding relationship between the transverse acoustic mode frequency and the diameter of the coating layer can be calculated. The coating layer thickness can be measured with high precision by measuring the frequency spectrum of forward Brillouin scattering corresponding to multiple transverse acoustic modes at a given temperature. In the verification experiment, three types of single-mode fibers coated with polyimide are used as the sensing fiber to measure the thickness of the coating layer at multiple temperatures. The experimental results show that the error in the coating layer thickness obtained is less than 0.05 μm. To the best of our knowledge, this is the first demonstration of non-destructive, high-precision monitoring of fiber coating thickness. © 2001-2012 IEEE.

关键词： Acoustic field measurement

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Influence of the Unloading system on Solar Array Attitude Adjustment in Ground Tests

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Journal of Vibration Engineering and Technologies 2025年第5期13卷 1-14页

作者： Zhang, Yijia Wu, Zhiqiang Zhang, Shicheng Zhong, Hongliang Liu, Yuang Li, Yuehua Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin University Tianjin 300350 China Tianjin Institute of Aerospace Mechanical and Electrical Equipment Tianjin 300458 China Tianjin Key Laboratory of Aerospace Intelligent Equipment Technology Tianjin 300458 China Beijing Institute of Spacecraft System Engineering Beijing 100094 China

Purpose: Conducting the attitude adjustment tests of the solar array on the ground is highly significant. However, the introduction of the gravity unloading system that can meet large-amplitude movements will cause changes in the dynamic characteristics of the system. This paper aims to guide the design of the unloading system by analyzing its influence and verify the reliability of the ground experiment. Methods: Polycondensation and Lagrangian energy method are used to establish a low-degree-of-freedom model, which can reflect the dynamic characteristics of the ground attitude adjustment system. Eigenvalue analysis and system response analysis are used to analyze the influence of the unloading system and its parameters. Results: Through eigenvalue analysis, it is found that the magnetic-pneumatic suspension unloading system adopted in this paper will introduce an additional mode to the attitude adjustment system, causing the original fundamental frequency of the system to split into two. By selecting a small mass for the hybrid magnetic element, the fundamental frequency error between the ground and space systems can be controlled within an acceptable range. The additional mode will be introduced at a relatively high frequency, minimizing its effect. Through the analysis of the response, it is found that the maximum value of the response of the system in the ground test state is mainly determined by the driving impact and is less affected by the unloading system. Therefore, it can reflect the space state well. However, due to the unloading system, both the fundamental frequency and the damping ratio show a decreasing trend, which will reduce the decay rate of the system, and will decrease further with the increase of the mass of the hybrid magnetic element. In addition, the synchronization of the vibrations between the simulator and the unloading system is also affected by the mass of the hybrid magnetic element. Conclusion: By reasonably designing the unloading s

关键词： Ground-space difference Magnetic-pneumatic suspension system Parameter influence SADA Solar array

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Edge-Assisted Flexible Platooning of Connected and Automated Vehicles Under Traffic Anomaly

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IEEE Transactions on Vehicular Technology 2025年

作者： Gao, Fengkun Yang, Bo Chen, Cailian Guan, Xinping Shanghai Jiao Tong University Department of Automation Shanghai200240 China Ministry of Education of China Key Laboratory of System Control and Information Processing Shanghai200240 China Shanghai Engineering Research Center of Industrial Intelligent Control and Management Shanghai200240 China

The platooning of connected and automated vehicles (CAVs) has the great potential to significantly improve travel experience in terms of safety, comfortableness, and energy efficiency. However, constrained by sensing range and prediction accuracy, the performance of CAV platoon can not be guaranteed in the scenario of mixed traffic consisting of CAVs and human-driven vehicles (HDVs). This is not only due to the uncertainty of HDVs but also related to the occurrence of various traffic anomalies, such as emergency braking and accidents. In this paper, we aim to investigate an efficient control strategy to guarantee the operation of the platoon in mixed traffic, especially in the case of traffic anomalies. To tackle the problem, an edge-assisted platoon control strategy, called E-CACC, is proposed. First, an error-aware flexible tracking policy is designed to adapt to HDV uncertainties and speed prediction errors. Based on the tracking policy, a zone model predictive control (ZMPC) method is then designed to guarantee travel safety and avoid undesired acceleration. Further, a coordination strategy of CAV platoon and roadside unit (RSU) is proposed to prevent the platoon from potential collision in the case of traffic anomalies, where an event-based communication trigger is designed to determine whether and when the platoon establishes communication links with RSU to acquire exogenous sensing data of anomaly segment. Finally, the evaluation results illustrate the effectiveness of the proposed method in improving travel safety and comfortableness. © 1967-2012 IEEE.

关键词： Braking performance

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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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Breaking the resolution-distance trade-off: 50-cm spatial resolution over 14 km using correlation demodulation in Raman distributed fiber sensors

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Optics letters 2025年第9期50卷 3014-3017页

作者： Zhang, Xinyue Li, Jian Fan, Bowen Cheng, Zijia Huang, Xin Xue, Xiaohui Zhang, Mingjiang College of Physics and Optoelectronics Taiyuan University of Technology Taiyuan 030024 China Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan 030024 China Shanxi Key Laboratory of Precision Measurement Physics Taiyuan University of Technology Taiyuan 030024 China

The spatial resolution and sensing distance of Raman distributed optical fiber sensors are constrained by the pulse width and the inherently weak Raman scattering signals. Consequently, the spatial resolution for kilometer-level detection distances is typically limited to the order of meters. To address this principle limitation, this study proposes a Raman distributed optical fiber sensing scheme based on amplified spontaneous emission (ASE) correlation detection. By performing a cross correlation operation between the ASE detection signal and the reconstructed Raman anti-Stokes signal, the system effectively captures the weaker intensity information of Raman anti-Stokes light, thereby enhancing spatial resolution. Experimental results demonstrate a spatial resolution of 50 cm over a distributed temperature-sensing distance exceeding 14.0 km.

关键词： Fiber optic sensors Optical fibers Raman scattering Spatial resolution Superconducting nanowire single photon detectors Variable optical attenuators

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Multiplexed model predictive attitude control for nadir-pointing satellite using only magnetorquers

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control Engineering Practice 2025年 162卷

作者： Yang, Sen Ling, Keck Voon Wang, Zhenhua Li, Huiping School of Astronautic Harbin Institute of Technology Harbin150001 China School of Electrical and Electronic Engineering Nanyang Technological University Singapore639798 Singapore National Key Laboratory of Complex System Control and Intelligent Agent Cooperation Harbin150001 China School of Marine Science and Technology Northwestern Polytechnical University Xi'an710072 China

Due to the low failure risk of magnetorquers, the control strategy based on magnetic actuators can significantly enhance the reliability of the satellite attitude control system. In light of this advantage, this paper conducts research on model predictive control (MPC) algorithm for nadir-pointing satellites equipped only with magnetorquers. Firstly, to facilitate controller design, the linear time-varying (LTV) model for nadir-pointing satellites is derived by linearizing the nonlinear equations around the operating point. Then, leveraging this linearized representation, an LTV multiplexed MPC (MMPC) method with exponential weighting is proposed. The MMPC scheme allows for faster sampling rates and quicker responses to disturbances, thereby enhancing the overall performance of the satellite attitude control system while retaining the benefits of MPC. Finally, compared with a state-of-the-art SMPC method, the proposed method is particularly advantageous in situations where computational resources are limited, specifically for satellites that rely only on onboard computing capabilities. © 2025

关键词： Nonlinear equations

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Adaptive Artificial Potential Field Ship Motion Planning Based on DDPG

Adaptive Artificial Potential Field Ship Motion Planning Bas...

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International Conference on Artificial Intelligence and Autonomous Transportation, AIAT 2024

作者： Chen, Huimin Liu, Chenguang He, Zhibo Zhang, Guoqing Han, Bing State Key Laboratory of Maritime Technology and Safety Wuhan University of Technology Wuhan430063 China Intelligent Transportation Systems Research Center Wuhan University of Technology Wuhan430063 China School of Transportation and Logistics Engineering Wuhan University of Technology Wuhan430063 China Navigation College Dalian Maritime University Dalian116026 China State Key Laboratory of Maritime Technology and Safety Dalian116026 China National Engineering Research Center of Ship & Shipping Control System Shanghai200134 China

ISBN: (纸本)9789819639601

The paper presents a ship motion planning method that adjusts the attractive and repulsive gain parameters of the artificial potential field (APF) algorithm using the deep deterministic policy gradient (DDPG) algorithm, to address the challenges of parameter design and limited adaptability of traditional APF algorithms. This approach leverages the speed advantage of the APF planning algorithm and the exploration capability of the DDPG reinforcement learning algorithm. By optimizing the parameters of APF with DDPG, the local optima problem can be alleviated in complex obstacle environments. Simulation results demonstrate that the proposed motion planning algorithm can generate reasonable trajectories and exhibit strong adaptability in complex obstacle scenarios. © Beijing Paike Culture Commu. Co., Ltd. 2025.

关键词： Motion planning

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Designing high-Q Fano resonance structures for enhancing fluorescence in all-dielectric metasurfaces

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Optics letters 2025年第9期50卷 2930-2933页

作者： He, Shuai Wang, Zhiyuan Han, Bin Li, Shan Yao, Zhenyu Guo, Yulong Chen, Zhihui Wang, Yang Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education College of Physics and Optoelectronics Taiyuan University of Technology Taiyuan 030024 China Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Institute of Biotechnology Shanxi University Taiyuan 030006 China

Highly sensitive fluorescence detection technology is crucial for biological sensing, imaging, and photonic technologies. The fluorescence enhancement effect with the same enhancement factor at multi-wavelengths is important for highly sensitive detection. However, achieving multi-wavelength fluorescence enhancement remains challenging. Here, we introduce an all-dielectric metasurface composed of symmetry-broken silicon nanocylinders integrated with graphene, which is designed to significantly enhance and dynamically modulate the fluorescence emission of a single quantum dot. By fine-tuning structural parameters and adjusting the graphene Fermi level, we achieve a tunable high-Q Fano resonance, leading to a nearly 4000-fold fluorescence enhancement. Structural parameter adjustments enable consistent fluorescence enhancement across different wavelengths. Furthermore, at specific wavelengths, fluorescence enhancement can be similarly adjusted. The proposed structure can greatly expand the design strategy of heterogeneous all-dielectric metasurfaces with the same enhancement factor at multi-wavelengths.

关键词： Biosensors Chemical vapor deposition Electron beam lithography Fano resonance Q factor Surface plasmon resonance

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Application of Particle Swarm Optimization Algorithm Based on Adaptive Inertia Adjustment Strategy in Scheduling of the Coking Process

Application of Particle Swarm Optimization Algorithm Based o...

引用

26th International Conference on Industrial Technology, ICIT 2025

作者： Chen, Yiheng Yin, Fan Chen, Xiaochong Ren, Yi Hu, Jie Wu, Min School of Automation China University of Geosciences Wuhan430074 China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan430074 China Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education Wuhan430074 China

ISBN: (纸本)9798331521950

The sccheduling for pushing plan during the coking process critically affects the efficiency and stability of production. However, the complexity with mutiple-stage during production makes it difficult to design an efficient coke pushing plan. To address this issue, this paper proposes a scheduling method based on the particle swarm optimization algorithm. Firstly, the fuzzy c-means clustering is utilized to categorize actual operating conditions as either normal or abnormal, thereby facilitating the scheduling of pushing plan under disparate conditions. Subsequently, the scheduling problem for the pushing plan is transformed into a traveling salesman problem, and scheduling models under various conditions are established. Finally, to accelerate the convergence and enhance the algorithm's global search capability, an adaptive inertia adjustment strategy is employed to dynamically regulate the velocity and position of particles. The proposed method has been implemented in the coking process. Through the analysis of application results, the completion coefficient of pushing plan has been increased by 4.25%, demonstrating that the proposed has advantages in scheduling the pushing plan during the actual coking process. © 2025 IEEE.

关键词： Particle swarm optimization (PSO)

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Design of a Constant Current Output High Frequency AC-DC Converter for Battery Charging Applications

Design of a Constant Current Output High Frequency AC-DC Con...

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IEEE International Conference on Industrial Technology (ICIT)

作者： Zihao Wei Xiaoxian Song Liangwei Jin Dingbang Huang Sheng Zhang Zhijian Fang School of Future Technology China University of Geosciences Wuhan China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan China School of Automation China University of Geosciences Wuhan China

ISBN: (数字)9798331521950

ISBN: (纸本)9798331521967

How to realize the high power factor, high efficiency, miniaturization and high power density of AC-DC converter is the key problem of battery charging applications. In this paper, an isolated AC-DC converter is proposed. The input voltage is rectified by the first stage AC-DC conversion, and the output is stabilized by the series resonant converter at the secondary stage. A sinusoidal modulation method is adopted to realize the constant current output characteristic independent of load. Then through the output current control loop and the PFC control loop, the constant current output and input high power factor are realized. The design of high switching frequency and resonant frequency provides conditions for high power density and miniaturization of converter design. Finally, the simulation of rated power of 960W was built by Matlab-simulink, which verified the rationality of the converter design.

关键词： Reactive power Power system measurements Density measurement Switching frequency Modulation Resonant converters Stability analysis Batteries High frequency Voltage control

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