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29th International Conference on Computational and Experimental engineering and sciences, ICCES 2023

作者： Yu, Weizhuo Yue, Xiaokui Huang, Panxing Liu, Chuang National Key Laboratory of Aerospace Flight Dynamics School of Astronautics Northwestern Polytechnical University Xi’an710072 China Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control Engineering Beijing100094 China

ISBN: (纸本)9783031429866

Recent years have witnessed the rapid development of aerospace science and technology, and the orbital game technology has shown great potential value in the field of failed satellite maintenance, debris removal, etc. In this case, orbital game is often characterized by nonlinear dynamic model, unknown state information, high randomness, but the existing approaches to deal with game problem are difficult to be applied. The analytical method based on game theory is only applicable to simple scenarios, and it is challenging to find the optimal strategy for such complex scenarios as satellite swarm game. It should be noted that deep reinforcement learning has some research basis in the cooperative decision-making and control of multi-agents. In view of its powerful perception and decision ability, this paper applies deep reinforcement learning to solve the orbital game problem of satellite swarm. Firstly, the game scenario is modeled, where typical constraints, e.g., minimum time, optimal fuel, and collision avoidance, are taken into consideration in the game process, and then the multi-agent reinforcement learning algorithm is developed to solve the optimal maneuver strategy. The algorithm is based on the Actor-Critic architecture and uses a centralized training and decentralized execution approach to solve the optimal joint maneuver strategy. For different task scenarios, the action space, state observation space, and reward space are designed to introduce more rewards that match the specific game tasks to make the algorithm converge quickly, so that the satellite swarm emerges and executes better intelligent strategies to complete the corresponding game task. © 2024, The Author(s), under exclusive license to Springer Nature Switzerland AG.

关键词： Game theory

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Realization of a quadrupole topological insulator phase in a gyromagnetic photonic crystal

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National science Review 2024年第11期11卷 47-53页

作者： Peiheng Zhou Gui-Geng Liu Zihao Wang Shuwei Li Qindong Xie Yunpeng Zhang Subhaskar Mandal Xiang Xi Zhen Gao Longjiang Deng Baile Zhang National Engineering Research Center of Electromagnetic Radiation Control Materials Key Laboratory of Multi-spectral Absorbing Materials and Structures of Ministry of EducationUniversity of Electronic Science and Technology of China Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University School of Electrical Engineering and Intelligentization Dongguan University of Technology Department of Electronic and Electrical Engineering Southern University of Science and Technology Centre for Disruptive Photonic Technologies The Photonics InstituteNanyang Technological University

The field of topological photonics was initiated with the realization of a Chern insulator phase in a gyromagnetic photonic crystal(Ph C) with broken time-reversal symmetry(T), hosting chiral edge states that are topologically protected propagating modes. Along a separate line of research, a quadrupole topological insulator was the first higher-order topological phase supporting localized corner states, but has been so far limited to T-invariant systems, as T is a key ingredient in early models. Here we report the realization of a quadrupole topological insulator phase in a gyromagnetic Ph C, as a consequence of topological phase transition from the previously demonstrated Chern insulator phase. The phase transition has been demonstrated with microwave measurements, which characterize the evolution from propagating chiral edge states to localized corner states. We also demonstrate the migration of topological boundary states into the continuum, when the gyromagnetic Ph C is magnetically tuned. These results extend the quadrupole topological insulator phase into T-broken systems, and integrate topologically protected propagating and localized modes in a magnetically tunable photonic crystal platform.

关键词： quadrupole topological insulator time-reversal symmetry breaking corner states topological phase transition

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Residual Carrying Capacity Evaluation and Parking Orbit Replanning for Lunar Exploration Launch Vehicle

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Advances in Astronautics science and Technology 2024年第1期7卷 65-78页

作者： Wang, Cong Wang, Jinbo Song, Zhengyu Beijing Aerospace Automatic Control Institute Beijing100854 China School of Systems Science and Engineering Sun Yat-Sen University Guangzhou510275 China China Academy of Launch Vehicle Technology Beijing100076 China

To cope with the potential thrust-drop malfunction of the manned lunar exploration launch vehicle, a parking orbit replanning method is proposed based on the evaluation of the residual carrying capacity of the launcher. By analyzing the constraints of the whole flight profile and the characteristics of the Earth–Moon transfer orbit systematically, the offline trajectory planning algorithm exhibits improved convergence performance, and thus can be used to evaluate the residual carrying capacity as thrust-drop happens. For the situations that the launcher is not capable of injecting the transfer orbit, a sequential orbit/trajectory replanning method is designed to guarantee the safety of the astronauts. On the premise of ensuring the altitude of the parking orbit, the elements about the orbital plane are further optimized to provide a favorable initial state for the subsequent rescue action. Meanwhile, the nonlinearity of the terminal constraints is alleviated by the injection point forecast, and the initial reference is generated by convex optimization method with well convergence;thus, the solving efficiency of the sequential replanning algorithm can be improved. Simulation results show the proposed method can generate the trajectory that transport the spacecraft to the optimal parking orbit under the thrust-drop malfunction situation. This is an English translated version of "Residual Carrying Capacity Evaluation and Parking Orbit Re-planning for Lunar Exploration Launch Vehicle". © Chinese Society of Astronautics 2024. corrected publication 2024.

关键词： Lunar missions

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Research on Task Scheduling Algorithm of Shuttle based Storage and Retrieval System Based on Energy Consumption

Research on Task Scheduling Algorithm of Shuttle based Stora...

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2023 International Conference on Automation in Manufacturing, Transportation and Logistics, iCaMaL 2023

作者： Wang, Yanyan Ma, Xurui Qin, Jinning Mou, Shandong School of Control Science and Engineering Shandong University Jinan China Business School Central University of Finance and Economics Beijing China

ISBN: (纸本)9781839539954

Shuttle based storage and retrieval system (SBS/RS) has been applied in many automated warehouses because of its high space utilization, flexibility and response speed. The efficiency of task scheduling has a profound impact on the order picking efficiency,customer satisfaction and warehouse operation cost. In this study, based on the indepth analysis of the system operation flow, the service time of all kinds of equipment is calculated, and the equipment energy consumption model is constructed. A task green scheduling model is established to minimize the total energy consumption cost of outbound tasks. An improved particle swarm optimization is used to solve the model and compared with adaptive genetic algorithm and other algorithms to verify model accuracy by several numerical experiments. Low energy consumption can reduce the operating cost and bring more social benefits. The energy consumption costbased task scheduling model proposed in this research provides a new solution to the task scheduling problem. © The Institution of engineering & Technology 2023.

关键词： Energy Consumption Model Improved particle swarm optimization Shuttle Based Storage and Retrieval System Task Scheduling Model

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Multiple Four-way Shuttle Path Planning Problem in Shuttle-Based Storage and Retrieval Systems: An Improved Conflict-Based Search Algorithm 14

Multiple Four-way Shuttle Path Planning Problem in Shuttle-B...

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14th International Conference on Logistics and Systems engineering

作者： Wang, Yanyan Wang, Zefeng Wang, Xuemei Man, Rongjun Shenzhen Research Institute of Shandong University Guangdong Shenzhen518057 China School of Control Science and Engineering Shandong University Shandong Jinan250061 China

ISBN: (纸本)9798331314347

A unique automated warehousing system called the four-way shuttle system has gained popularity recently because of its high adaptability and capacity to function across aisles and tiers. The four-way shuttle can move in four directions along fixed guideways. Therefore, the conflict-free routing of multiple four-directional shuttles within the same layer becomes particularly significant. This study develops a mathematical model for optimizing conflict-free path planning for multiple four-way shuttles to minimize total task completion time. We introduce the Dynamic Potential Conflict-Based Search (DPCBS) algorithm to facilitate conflict-free navigation for four-way shuttles. DPCBS enhances the Conflict-Based Search (CBS) algorithm's high-level search strategy by integrating the Dynamic Potential Search algorithm and augments the low-level search strategy with the Safe Interval Path Planning algorithm. This algorithm also incorporates priority strategies to improve its efficacy. Experimental results show that DPCBS with the priority strategy significantly outperforms the original algorithm in computational efficiency and success rate, effectively generating conflict-free paths for the four-way shuttle system. © (2025) by Aussino Academic Publishing House All rights reserved.

关键词： Guideways

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Analysis of Friction Characteristics of Port Plate Pair in an Axial Piston Pump Under Instantaneous Working Conditions 9

Analysis of Friction Characteristics of Port Plate Pair in a...

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

作者： Han, Bo Wang, Zhaoqiang Ji, Hong Sun, Lingtao Lu, Yangjun School of Mechanical and Automotive Engineering Shanghai University of Engineering Science Shanghai China School of Fluid Power and Control Engineering Lanzhou University of Technology Lanzhou China

ISBN: (数字)9798350304947

ISBN: (纸本)9798350304947

In this paper, the lubrication model of the cylinder block/valve plate sliding interface of the axial piston pump considering elastic deformation under instantaneous working conditions is established. The oil film carrying pressure and asperity microcontact pressure are calculated using Reynolds equation, Greenwood-Williamson asperity micro contact model, Hertz contact theory. The dynamic analysis is carried out, and the Newton-Raphson iterative method is introduced to solve the nonlinear equations. The influence of operating pressure, cylinder speed and sealing belt width on the friction characteristics of the port plate pair is analyzed by using the numerical calculation model. The numerical analysis results reveal that three iterations have converged, that increasing speed and pressure can both increase friction and torque, and that adjusting the sealing belt width affects the oil film support area, resulting in a change in friction characteristics. © 2023 IEEE.

关键词： Elastohydrodynamic lubrication

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An optimized Fuzzy PI control method utilizing an improved QPSO for the hydrogen supply of PEMFC 18

An optimized Fuzzy PI control method utilizing an improved Q...

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18th IEEE Conference on Industrial Electronics and Applications, ICIEA 2023

作者： Xue, Haoyuan Zhang, Hailun Sun, Wenxu Yao, Ailing Jia, Lei Shandong University Institute of Marine Science and Technology Qingdao China Shandong University The School of Control Science and Engineering Jinan China

ISBN: (纸本)9798350312201

This paper proposes a Fuzzy logic PI control method for the hydrogen supply sub-system of the Proton Exchange Membrane Fuel Cell(PEMFC). The parameters of the controller are optimized using an improved Quantum-behaved Particle Swarm Optimization (QPSO) method. During the iterative optimization process with QPSO, the Logistic chaos mode is used to initialize the optimization algorithm by generating a set of random numbers as the initial population. The improved QPSO initialize method can effectively avoid the algorithm from getting stuck in local optima. The proposed control algorithm is based on a control-oriented model of the fuel cell, which established by combining the reaction process and the hydrogen supply and recirculation sub-system using the ejector. The hydrogen excess ratio and the ejector inlet pressure are controlled to the set value under load changes. The results indicate that the proposed control strategy has an improvement in regulation time and overshoot reduction of the hydrogen pressure and excess ratio compared with the traditional PID and fuzzy PI control strategies. © 2023 IEEE.

关键词： Fuzzy logic

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Effect of Water Soaking on the Microstructure and Spontaneous Combustion Characteristics of Bituminous Coal During Low−Temperature Oxidation

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Combustion science and Technology 2024年第11期196卷 1743-1767页

作者： Yi, Xin Zhang, Shaohang Bai, Zujin Deng, Jun Shu, Chimin Qu, Gaoyang Ge, Long School of Safety Science and Engineering Xi’an University of Science and Technology Shaanxi Xi’an China Shaanxi Key Laboratory of Prevention and Control of Coal Fire Xi’an University of Science and Technology Shaanxi Xi’an China Center for Process Safety and Disaster Prevention National Yunlin University of Science and Technology Yunlin Taiwan

The effects of water soaking on the microstructure and spontaneous combustion characteristics of coal samples were investigated by scanning electronic microscopy (SEM), Fourier transform infrared (FTIR) spectrometer, and temperature programmed testing system (TPTS). The SEM results showed that the pore structures on the surface of water−soaked coal were more developed than raw coal, the pores increased and enlarged, and the phenomenon of water absorption swelling occurred. At the same time, water soaking had a certain influence on the functional groups in coal. The results of FTIR clearly illustrated that the surface functional groups of water−soaked coal were more active, and the contents of functional groups such as hydroxyl, methylene, aliphatic ether and aromatic ether all increased to varying degrees. During the low−temperature oxidation process, the analysis results of TPTS indicated that the oxygen consumption rate and the production of CO, C2H4, and other gases of water−soaked coal were higher. Based on the analysis method of CO, CO/CO2 and C2H4 gas growth rate, the three peaks of the curve obtained correspond to the characteristic temperatures of each oxidation stage of the coal samples. The critical temperature, dry cracking temperature and fission temperature of water−soaked coal were 60 ± 10 ℃, 90 ± 10 ℃ and 120 ± 10 ℃, respectively, which was 10 ℃ lower than raw coal. The apparent activation energy (Ea) of coal was calculated by the CO model and fitted in sections. It can be seen that the Ea of water−soaked coal at different stages of low−temperature oxidation was lower, and the maximum difference was 2.1 kJ/mol. Therefore, from the above results, it inferred that the activity of bituminous coal became stronger after soaking in water, which may be due to the effect of soaking on the surface structure and active groups of coal, thus showing a higher risk of spontaneous combustion. © 2022 Taylor & Francis Group, LLC.

关键词： Temperature

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A voltage tracking control design of the single-phase inverter based on Linear ADRC 37

A voltage tracking control design of the single-phase invert...

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37th Youth Academic Annual Conference of Chinese Association of Automation, YAC 2022

作者： Qu, Dejian Li, Shengming Zhang, Jingyu Lv, Zongyang Dalian University of Technology School of Control Science and Technology Dalian China School of Control Science and Engineering Dalian University of Technology Dalian China

ISBN: (纸本)9781665465366

This paper analyzes the working principle of the single-phase inverter, studies the problems of slow dynamic response and weak anti-interference ability of the existing PI controller scheme inverter, and designs a linear active disturbance rejection controller. Under this control method, the dynamic response performance and anti-interference ability of the inverter have been significantly improved compared with the PI controller. In this paper, the bandwidth method is used to simplify the design of ADRC and the parameters are set. The control effect is verified by bus jump and load jump. The simulation is carried out in Simulink, and the experimental platform is built to verify the scheme. The simulation and experimental results verify the effectiveness of the LADRC controller, as well as stronger dynamic response performance and anti-interference ability compared with the PI controller. © 2022 IEEE.

关键词： Bandwidth

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Embedded Multi-Port Converters for Synthesis and Enhancement of Hybrid-Clamped Multilevel Converters

Embedded Multi-Port Converters for Synthesis and Enhancement...

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2023 IEEE Energy Conversion Congress and Exposition, ECCE 2023

作者： Li, Yuzhuo Gunawardena, Pasan Tian, Hao Li, Yunwei University of Alberta Department of Electrical and Computer Engineering Edmonton Canada Shandong University School of Control Science and Engineering Jinan China

ISBN: (纸本)9798350316445

Leveraging a number of inner capacitors/inductors, hybrid-clamped multilevel converters (MLCs) normally face great challenges among good performance (proper charge/discharge of these devices), high efficiency (maintaining low losses) and high power density (compact profile). On the other hand, these multiple-device energy-processing requirements have been addressed well in some promising multi-port converters (MPCs), and, therefore, inspire us to implement well-developed compact MPCs to facilitate the voltage/current level generation process in hybrid-clamped MLCs. Though recently, some researchers started to integrate active cells into hybrid-clamped MLCs and improve capacitor voltage control and generate extra output levels, the systematic synthesis method is still unclear and rarely discussed in the literature. To address this gap, we propose a systematic synthesis method for those hybrid clamped MLCs that can benefit from embedding well-developed MPCs. The approach can be applied for both voltage-source and current-source hybrid-clamped MLCs, covering emerging MLCs. In particular, we also derived and verified a new mixed hybrid MLC family through an emerging current-fed dual-input isolated multi-port converter. This topology features both current-source and voltage-source benefits and is ideal for future renewable generation integration. © 2023 IEEE.

关键词： Converters Synthesis Hybrid-Clamped Multi-level Converters Multi-port Converters

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