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Cooperative formation control of multiple aerial vehicles based on guidance route in a complex task environment

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Chinese Journal of Aeronautics 2020年第2期33卷 701-720页

作者： Guibin SUN Rui ZHOU Kun XU Zhi WENG Yuhang ZHANG Zhuoning DONG Yingxun WANG School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China State Key Laboratory of Software Development Environment Beihang UniversityBeijing 100083China College of Electronic Information Engineering Inner Mongolia UniversityHohhot 010021China

In recent years,formation control of multi-agent has been a significant research subject in the field of cooperative control.However,previous works have mainly concentrated on formation control for simple point-mass model and linear model.In contrast,this paper presents a novel cooperative algorithm for multiple air vehicles formation control,which aims to devise a control strategy based on guidance route to achieve precisely coordinated formation control for a group of fixed-wing aircraft in a complex task environment.The proposed method introduces the leader-follower structure for effective organization of the multi-agent coordination.Moreover,the Partial Integrated formation and Control(PIFC)is adopted to design the control law for Guidance-Route based formation Control(GRFC).Additionally,the proposed approach designs two guidance-route generation strategies for two special situations to demonstrate the effectiveness of GRFC in complex task environments.Theoretical analysis reveals that the proposed control protocol for guidance command can ensure the overall stability and tracking accuracy of the system.Numerical simulations are performed to illustrate the theoretical results,and verify that the proposed approach can achieve coordinated formation control precisely in a complex task environment.

关键词： Complex task environments Cooperative formation control Fixed-wing aircraft Guidance route Leader-follower structure Partial integrated formation and control

Multi-target pursuit formation of multi-agent systems

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Chinese Physics B 2011年第1期20卷 698-707页

作者：闫敬关新平罗小元 Institute of Electrical Engineering Yanshan University School of Electronic and Electric Engineering Shanghai Jiaotong University

The main goal of this paper is to design a team of agents that can accomplish multi-target pursuit formation using a developed leader-follower strategy. It is supposed that every target can accept a certain number of agents. First, each agent can automatically choose its target based on the distance from the agent to the target and the number of agents accepted by the target. In view of the fact that all agents are randomly dispersed in the workplace at the initial time, we present a numbering strategy for them. During the movement of agents, not every agent can always obtain pertinent state information about the targets. So, a developed leader-follower strategy and a pursuit formation algorithm are proposed. Under the proposed method, agents with the same target can maintain a circle formation. Furthermore, it turns out that the pursuit formation algorithm for agents to the desired formation is convergent. Simulation studies are provided to illustrate the effectiveness of the proposed method.

关键词： multi-agent systems pursuit formation leader-follower

Peculiarities of the rheological behavior and structure formation of aluminum under deformation at near-solidus temperatures

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International Journal of Minerals,Metallurgy and Materials 2016年第5期23卷 563-571页

作者： A. S. Smirnov A. V. Konovalov G. A. Belozerov V. P. Shveikin E. O. Smirnova Institute of Engineering Science Russian Academy of Science (Ural Branch) 34 Komsomolskaya Street Ekaterinburg 620049 Russia Ural Federal University 19 Mira Street Ekaterinburg 620002 Russia

This paper deals with a peculiar rheological behavior of aluminum at near-solidus temperatures. It has been experimentally estab- lished that there is an inverse strain rate dependence of strain resistance at temperatures ranging between 560 and 640℃ and strain rates ranging from 0.06 to 1.2 s-1. Electron backscatter diffraction analysis has shown that at temperatures ranging between 540 and 640℃ and strain rates ranging from 0.06 to 0.1 s-1, the main process of softening is dynamic polygonization, resulting in in situ recrystallization. At higher strain rates, ranging between 0.8 and 1.2 s-1, and temperatures ranging between 560 and 640℃, the recovery is dynamic. This unusual behavior of the mechanism of softening and the presence of the inverse strain rate dependence of strain resistance can be explained by blocking the motion of free dislocations by foreign atoms, which occurs at strain rates ranging between 0.06 and 0.1 s-1 This process results in dislocation pile-up, thereby causing in sire recrystallization. At strain rates exceeding 0.16 s-1, there is no intensive blocking of dislocations, leading to a direct strain rate dependence of strain resistance.

关键词： aluminum rheological behavior formation near-solidus temperature

Insight into the formation mechanism of levoglucosenone in phosphoric acid-catalyzed fast pyrolysis of cellulose

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Journal of Energy Chemistry 2020年第4期29卷 78-89页

作者： Bin Hu Qiang Lu Yu-ting Wu Wen-luan Xie Min-shu Cui Ji Liu Chang-qing Dong Yong-ping Yang National Engineering Laboratory for Biomass Power Generation Equipment North China Electric Power UniversityBeijing 102206China

The catalytic fast pyrolysis of cellulose impregnated with phosphoric acid (H3PO4) offers a promising method for the selective production of levoglucosenone (LGO),a valuable anhydrosugar product.However,the fundamental mechanism for selective LGO formation is unclear.Herein,quantum chemistry calculations and catalytic fast pyrolysis experiments were performed to reveal the formation mechanism of LGO in H3PO4-catalyzed cellulose pyrolysis.H3PO4 significantly decreased the energy barriers of the pyrolytic reactions and altered the competitiveness of the LGO formation pathways,promoting LGO formation.Through different pathways in the non-catalytic and H3P04-catalyzed conditions,LGO is mainly produced from the primary decomposition of glucose units of cellulose and secondary conversion of levoglucosan.The major catalytic formation pathways of LGO comprise similar reactions,with dehydration at the 3-OH+2-H site as the rate-determining step.Importantly,secondary conversion of 1,4;3,6-dianhydro-α-D-glucopyranose is not feasible for LGO formation,in contrast to previous reports.In addition,a high degree of polymerization is beneficial for the selectivity of LGO formation in the catalytic process,because the glycosidic bond is important for the formation of the bicyclic structure (1,5-and1,6-acetal rings).

关键词： Phosphoric acid Levoglucosenone formation mechanism Density functional theory Py-GC/MS

Spacecraft formation-containment flying control with time-varying translational velocity

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Chinese Journal of Aeronautics 2020年第1期33卷 271-281页

作者： Liangming CHEN Chuanjiang LI Yanning GUO Guangfu MA Baolong ZHU Department of Control Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Electrical Engineering and Automation Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China

This paper investigates the problem of Spacecraft formation-Containment Flying Control(SFCFC)when the desired translational velocity is time-varying.In SFCFC problem,there are multiple leader spacecraft and multiple follower spacecraft and SFCFC can be divided into leader spacecraft’s formation control and follower spacecraft’s containment control.First,under the condition that only a part of leader spacecraft can have access to the desired time-varying translational velocity,a velocity estimator is designed for each leader spacecraft.Secondly,based on the estimated translational velocity,a distributed formation control algorithm is designed for leader spacecraft to achieve the desired formation and move with the desired translational velocity simultaneously.Then,to ensure all follower spacecraft converge to the convex hull formed by the leader spacecraft,a distributed containment control algorithm is designed for follower spacecraft.Moreover,to reduce the dependence of the designed control algorithms on the graph information and increase system robustness,the control gains are changing adaptively and the parametric uncertainties are handled,respectively.Finally,simulation results are provided to illustrate the effectiveness of the theoretical results.

关键词： Adaptive gain technique Distributed control formation-containment formation control Spacecraft formation flying

Sliding Mode formation Control of Nonlinear Multi-Agent Systems with Local Lipschitz Continuous Dynamics

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Journal of Systems Science & Complexity 2019年第3期32卷 759-777页

作者： WANG Jinran LUO Xiaoyuan LI Xiaolei ZHU Minggao GUAN Xinping School of Electrical Engineering Yanshan University Qinhuangdao 066004 China Branch of Light Industry Beijing Industry and Trade Technicians College Beijing 100079 China Institute of Electronic Information and Electrical Engineering Shanghai Jiao Tong University Shanghai 200240 China

In this paper, the multi-agent formation problem of networked nonlinear multi-agent systems with local Lipschitz continuous dynamics under directed interaction topology, is investigated. Based on the nonlinear dynamics satisfying locally Lipschitz continuous conditions, three kinds of sliding mode controllers are proposed to solve the problem of multi-agent formation control. Using integral sliding mode controller in first-order system, formation shape is achieved within finite time. For second-order system, on the one hand, non-singular terminal sliding mode function is adopted to accomplish the system asymptotic convergence. Furthermore, super-twisting algorithm is proposed to make multi-agent achieve the desired formation within finite time. Lyapunov functions are applied in the whole paper to ensure the system stability. Numerical simulation examples are provided to demonstrate the effectiveness of the proposed sliding mode control methods.

关键词： formation control nonlinear multi-agent system sliding mode super-twisting algorithm

Time-varying fault-tolerant formation tracking based cooperative control and guidance for multiple cruise missile systems under actuator failures and directed topologies

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Journal of Systems Engineering and Electronics 2019年第3期30卷 587-600页

作者： XU Xingguang WEI Zhenyan REN Zhang LI Shusheng School of Automation Science and Electrical Engineering Beihang University Beijing 100191 China Beijing Institute of Mechanical and Electrical Engineering Beijing 100074 China Beijing Aerospace Technology Institute Beijing 100074 China

This paper studies time-varying fault-tolerant formation tracking problems for the multiple cruise missile system under directed topologies subjected to actuator failures. Firstly, the timevarying fault-tolerant formation tracking process for the multiple cruise missile system is divided into the guidance loop and the control loop. Then protocols are constructed to accomplish distributed fault-tolerant formation tracking in the guidance loop with the adaptive updating mechanism, in the condition where neither the knowledge about actuator malfunctions nor any global information of the communication topology remains available. Moreover, sufficient conditions to accomplish formation tracking are presented, and it is shown that the multiple cruise missile system can carry on the predefined time-varying fault-tolerant control (FTC) formation tracking through the active disturbances rejection controller (ADRC) and the proportion integration (PI) controller by the way of the fault-tolerant protocol utilizing the designed strategies, in the event of actuator failures. At last, numerical analysis and simulation are designed to verify the theoretical results.

关键词： fault-tolerant formation tracking consensus-based cruise missile active disturbances rejection controller (ADRC)

Effect of H2 addition on process of primary slag formation in cohesive zone

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Journal of Iron and Steel Research(International) 2020年第2期27卷 132-140页

作者： Ya-na Qie Qing Lyu Chen-chen Lan Shu-hui Zhang Ran Liu College of Metallurgy and Energy Key Laboratory for Advanced Metallurgy TechnologyNorth China University of Science and TechnologyTangshan 063009HebeiChina

Based on the technology of gas-injection blast furnace(BF),the characteristics of primary slag formation with H2 addition were researched.The results indicate that,compared with traditional BF,the primary melt is formed at a lower temperature,which promotes the deformation of the solid burden particles.With the increase in temperature and H2 content,the quantity of formed melt containing FeO decreases sharply,corresponding to the crystallization of solid 2CaO Si02 during reduction.A wider softening range and narrower melting zone could be found in the gas-injection BF with a higher reduction potential.The permeability of burden layer is ameliorated as a result of decreased melt quantity.The influence of H2 on the high-temperature properties of burden is not so conspicuous when the H2 addition is from 10 to 15 vol.%against 5 to 10 vol.%.What is more,the slag shows a better liquidity with the decrease in basicity,owing to the transformation of melt composition from a primary phase field with high melting point to that with low melting point.The process of slag forming in gas-injection BF is characterized by earlier melt formation,less primary slag,higher melting temperature,better permeability and better liquidity,and the phase compositions of primary slag are close to those of final slag.

关键词： Reduction degradation Primary slag formation Melt Hydrogen addition Gas-injection blast furnace

Growth kinetics of hydrate formation from water–hydrocarbon system

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Chinese Journal of Chemical Engineering 2019年第9期27卷 2164-2179页

作者： Youhong Sun Shuhui Jiang Shengli Li Guobiao Zhang Wei Guo Key Laboratory of Drilling and Exploitation Technology in Complex Conditions of Natural Resources College of Construction Engineering Jilin University

Gas hydrates have drawn global attentions in the past decades as potential energy resources.It should be noted that there are a variety of possible applications of hydrate-based technologies,including natural gas storage,gas transportation,separation of gas mixture,and seawater desalination.These applications have been critically challenged by insufficient understanding of hydrate formation kinetics.In this work,the literatures on growth kinetic behaviors of hydrate formation from water-hydrocarbon were systematically reviewed.The hydrate crystal growth,hydrate film growth and macroscopic hydrate formation in water system were reviewed,respectively.Firstly,the hydrate crystal growth was analyzed with respect to different positions,such as gas/liquid interface,liquid–liquid interface and gas–liquid–liquid system.Secondly,experimental and modeling studies on the growth of hydrate film at the interfaces between guest phase and water phase were categorized into two groups of lateral growth and thickening growth considering the differences in growth rates.Thirdly,we summarized the promoters and inhibitors reported(biological or chemical,liquid or solid and hydrophobic or hydrophilic)and analyzed the mechanisms affecting hydrate formation in bulk water system.Knowledge gaps and suggestions for further studies on hydrate formation kinetic behaviors are presented.

关键词： Gas hydrate formation Crystal Film Promotion Inhibition