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Strategy dominance mechanism of autonomous collaboration in unmanned swarm within the framework of public goods game

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系统工程与电子技术:英文版 2023年第5期34卷 1252-1266页

作者： PAN Li WU Zhonghong YU Minggang LIU Jintao MEI Dan Weaponry engineering college Naval University of EngineeringWuhan 430000China Electronics engineering college Naval University of EngineeringWuhan 430000China Coastal Defense college Naval Aeronautical UniversityYantai 264001China Qingdao Campus Naval Aeronautical UniversityQingdao 266000China

The key advantage of unmanned swarm operation is its autonomous cooperation. How to improve the proportion of cooperators is one of the key issues of autonomous collaboration in unmanned swarm operations. This work proposes a strategy dominance mechanism of autonomous collaboration in unmanned swarm within the framework of public goods game. It starts with the requirement analysis of autonomous collaboration in unmanned swarm;and an aspiration-driven multiplayer evolutionary game model is established based on the requirement. Then the average abundance function and strategy dominance condition of the model are constructed by theoretical derivation. Furthermore, the evolutionary mechanism of parameter adjustment in swarm cooperation is revealed via simulation,and the influences of the multiplication factor r, aspiration levelα, threshold m and other parameters on the strategy dominance conditions were simulated for both linear and threshold public goods games(PGGs) to determine the strategy dominance characteristics;Finally, deliberate proposals are suggested to provide a meaningful exploration in the actual control of unmanned swarm cooperation.

关键词： unmanned combat swarm autonomous collabora-tion strategy dominance multi-player public goods game(PGG)

Design and Testing of a Novel Piezoelectric-Driven Microvibration Hammerhead

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Nanomanufacturing and Metrology 2023年第1期6卷 79-87页

作者： Zhiyong Guo Zhemin Shen Weidong Liu Zhiqiang Zhang Lifeng Zhang Xuhao Wang college of aeronautical engineering Civil Aviation University of ChinaTianjin 300300China

A novel microvibration hammerhead consists of a piezoelectric actuator and a double cross-shape compliant mechanism(DCCM)is presented in this paper.The output force of the piezoelectric actuator can be detected in real time by an insideinstalled pressure sensor.A theoretical model including the stiffness,first natural frequency,and stress of the DCCM and the displacement output of the piezoelectric actuator are established,and then they are further analyzed using the finite element analysis method.The effects of the beam thickness on the static and dynamic properties are deeply analyzed and compared.A prototype micro hammering system is constructed by integrating the microvibration hammerhead assembly and controlling system.Various experiments are also carried out to verify the basic performance of the micro hammering system.

关键词： Piezoelectric Flexure hinge Micro hammering

Generalized mixed finite element method for 3D elasticity problems

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Acta Mechanica Sinica 2018年第2期34卷 371-380页

作者： Guanghui Qing Junhui Mao Yanhong Liu college of aeronautical engineering Civil Aviation University of China

Without applying any stable element techniques in the mixed methods, two simple generalized mixed element(GME) formulations were derived by combining the minimum potential energy principle and Hellinger–Reissner(H–R) variational principle. The main features of the GME formulations are that the common C0-continuous polynomial shape functions for displacement methods are used to express both displacement and stress variables, and the coefficient matrix of these formulations is not only automatically symmetric but also invertible. Hence, the numerical results of the generalized mixed methods based on the GME formulations are stable. Displacement as well as stress results can be obtained directly from the algebraic system for finite element analysis after introducing stress and displacement boundary conditions simultaneously. Numerical examples show that displacement and stress results retain the same accuracy. The results of the noncompatible generalized mixed method proposed herein are more accurate than those of the standard noncompatible displacement method. The noncompatible generalized mixed element is less sensitive to element geometric distortions.

关键词： Minimum potential energy principle Hellinger–Reissner (H–R) variational principle Generalized variational principle Generalized mixed element (GME) Elasticity problem Noncompatible mode

Airframe Damage Region Division Method Based on Structure Tensor Dynamic Operator

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Journal of Shanghai Jiaotong university(Science) 2022年第6期27卷 757-767页

作者：蔡舒妤师利中 college of aeronautical engineering Civil Aviation University of ChinaTianjin 300300China

In order to improve the accuracy of damage region division and eliminate the interference of damage adjacent region,the airframe damage region division method based on the structure tensor dynamic operator is proposed in this paper.The structure tensor feature space is established to represent the local features of damage images.It makes different damage images have the same feature distribution,and transform varied damage region division into consistent process of feature space division.On this basis,the structure tensor dynamic operator generation method is designed.It integrates with bacteria foraging optimization algorithm improved by defining double fitness function and chemotaxis rules,in order to calculate the parameters of dynamic operator generation method and realize the structure tensor feature space division.And then the airframe damage region division is realized.The experimental results on different airframe structure damage images show that compared with traditional threshold division method,the proposed method can improve the division quality.The interference of damage adjacent region is eliminated.The information loss caused by over-segmentation is avoided.And it is efficient in operation,and consistent in process.It also has the applicability to different types of structural damage.

关键词： airframe damage region division dynamic operator structure tensor feature distribution double fitness function intelligent maintenance

Highly accurate symplectic element based on two variational principles

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Acta Mechanica Sinica 2018年第1期34卷 151-161页

作者： Guanghui Qing Jia Tian college of aeronautical engineering Civil Aviation University of China

For the stability requirement of numerical resultants, the mathematical theory of classical mixed methods are relatively complex. However, generalized mixed methods are automatically stable, and their building process is simple and straightforward. In this paper, based on the seminal idea of the generalized mixed methods, a simple, stable, and highly accurate 8-node noncompatible symplectic element(NCSE8) was developed by the combination of the modified Hellinger-Reissner mixed variational principle and the minimum energy principle. To ensure the accuracy of in-plane stress results, a simultaneous equation approach was also suggested. Numerical experimentation shows that the accuracy of stress results of NCSE8 are nearly the same as that of displacement methods, and they are in good agreement with the exact solutions when the mesh is relatively fine. NCSE8 has advantages of the clearing concept, easy calculation by a finite element computer program, higher accuracy and wide applicability for various linear elasticity compressible and nearly incompressible material problems. It is possible that NCSE8 becomes even more advantageous for the fracture problems due to its better accuracy of stresses.

关键词： Modified H-R mixed variational principle Partial-mixed element Noncompatible symplectic element Finite element method Nearly incompressible material

A numerical optimization of high altitude testing facility for wind tunnel experiments

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Chinese Journal of Aeronautics 2015年第3期28卷 636-648页

作者： J.Bruce Ralphin Rose G.R.Jinu C.J.Brindha Department of aeronautical engineering Regional Centre of Anna University Department of Mechanical engineering University College of EngineeringNagercoil Department of aeronautical engineering The Raajas Engineering College

Abstract High altitude test facilities are required to test the high area ratio nozzles operating at the upper stages of rocket in the nozzle full flow conditions. It is typically achieved by creating the ambient pressure equal or less than the nozzle exit pressure. On average, air/GN2 is used as active gas for ejector system that is stored in the high pressure cylinders. The wind tunnel facilities are used for conducting aerodynamic simulation experiments at/under various flow velocities and operating conditions. However, constructing both of these facilities require more laboratory space and expensive instruments. Because of this demerit, a novel scheme is implemented for conducting wind tunnel experiments by using the existing infrastructure available in the high altitude testing （HAT） facility. This article presents the details about the methods implemented for suitably modifying the sub-scale HAT facility to conduct wind tunnel experiments. Hence, the design of nozzle for required area ratio A/A＊, realization of test section and the optimized configuration are focused in the present analysis. Specific insights into various rocket models including high thrust cryogenic engines and their holding mechanisms to conduct wind tunnel experiments in the HAT facility are analyzed. A detailed CFD analysis is done to propose this conversion without affecting the existing functional requirements of the HAT facility.

关键词： CFD Enclosed free-jet section Ground testing High altitude testing （HAT）facility Optimization

A review of recent advancements in finite element formulation for sandwich plates

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Chinese Journal of Aeronautics 2019年第4期32卷 785-798页

作者： Shehzaib IRFAN Faisal SIDDIQUI Aerospace engineering Department College of Aeronautical Engineering National University of Sciences and TechnologyRisalpur

Use of composite structures is exponentially growing in different fields due to their higher strength-to-weight ratio. This application trend requires that accurate theoretical explanations and their finite element models be developed for analyzing sandwich plates before finalizing the designs. This paper reviews the recent research trends of finite element formulations developed for analyzing sandwich plates. This paper reviews the finite element models developed after the year 2000. Initially, the finite element formulations based on first order shear deformation theory, higher order shear deformation theories, mixed solid-shell elements, zig-zag theories and global–local theories are presented. Then, some finite element formulations developed to analyze a very new class of structures called piezoelectric structures are presented. At the end, some formulations to analyze a very critical phenomenon called buckling are presented.

关键词： Buckling Finite element FSDT HSDT Laminated composites Piezoelectric Sandwich plates Zig-zag theory

An Exploration on Adaptive Iterative Learning Control for a Class of Commensurate High-order Uncertain Nonlinear Fractional Order Systems

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IEEE/CAA Journal of Automatica Sinica 2018年第2期5卷 618-627页

作者： Jianming Wei Youan Zhang Hu Bao School of Weaponry engineering Naval University of Engineering college of engineering Yantai Nanshan University aeronautical college Yantai Nanshan University

This paper explores the adaptive iterative learning control method in the control of fractional order systems for the first time. An adaptive iterative learning control(AILC) scheme is presented for a class of commensurate high-order uncertain nonlinear fractional order systems in the presence of disturbance.To facilitate the controller design, a sliding mode surface of tracking errors is designed by using sufficient conditions of linear fractional order systems. To relax the assumption of the identical initial condition in iterative learning control(ILC), a new boundary layer function is proposed by employing MittagLeffler function. The uncertainty in the system is compensated for by utilizing radial basis function neural network. Fractional order differential type updating laws and difference type learning law are designed to estimate unknown constant parameters and time-varying parameter, respectively. The hyperbolic tangent function and a convergent series sequence are used to design robust control term for neural network approximation error and bounded disturbance, simultaneously guaranteeing the learning convergence along iteration. The system output is proved to converge to a small neighborhood of the desired trajectory by constructing Lyapnov-like composite energy function(CEF)containing new integral type Lyapunov function, while keeping all the closed-loop signals bounded. Finally, a simulation example is presented to verify the effectiveness of the proposed approach.

关键词： Adaptive iterative learning control(AILC) boundary layer function composite energy function(CEF) fractional order differential learning law fractional order nonlinear systems Mittag-Leffler function

Design concepts of an aircraft wing： composite and morphing airfoil with auxetic structures

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Frontiers of Structural and Civil engineering 2016年第4期10卷 394-408页

作者： P R BUDARAPU Sudhir Sastry Y B R NATARAJAN Department of Aerospace engineering Indian Institute of Science Bangalore 560 012 India Department of aeronautical engineering College of Engineering Defence University Ethiopia Department of aeronautical engineering Institute of Aeronautical Engineering Hyderabad India

This paper is categorized into two parts. （1） A frame work to design the aircraft wing structure and （2） analysis ofa morphing airfoil with auxetic structure. The developed design frame work in the first part is used to arrive at the sizes of the various components of an aircraft wing structure. The strength based design is adopted, where the design loads are extracted from the aerodynamic loads. The aerodynamic loads acting on a wing structure are converted to equivalent distributed loads, which are further converted point loads to arrive at the shear forces, bending and twisting moments along the wing span. Based on the estimated shear forces, bending and twisting moments, the strength based design is employed to estimate the sizes of various sections of a composite wing structure. A three dimensional numerical model of the composite wing structure has been developed and analyzed for the extreme load conditions. Glass fiber reinforced plastic material is used in the numerical analysis. The estimated natural frequencies are observed to be in the acceptable limits. Furthermore, the discussed design principles in the first part are extended to the design of a morphing airfoil with auxetic structure. The advantages of the morphing airfoil with auxetic structure are （i） larger displacement with limited straining of the components and （ii） unique deformation characteristics, which produce a theoretical in-plane Poisson＇s ratio of -1. Aluminum Alloy AL6061-T651 is considered in the design of all the structural elements. The compliance characteristics of the airfoil are investigated through a numerical model. The numerical results are observed to be in close agreement with the experimental results in the literature.

关键词： wing design aerodynamic loads morphing airfoil auxetic structures negative Poisson＇s ratio