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An Intelligent Framework for Resilience Recovery of FANETs with Spatio-Temporal Aggregation and Multi-Head Attention Mechanism

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Computers, Materials & Continua 2024年第5期79卷 2375-2398页

作者： Zhijun Guo Yun Sun YingWang Chaoqi Fu Jilong Zhong Air Traffic Control and Navigation College Air Force Engineering UniversityXi’an710000China institute of Systems Engineering Academy of Military ScienceBeijing100101China Equipment Management and uav Engineering College Air Force Engineering UniversityXi’an710038China Defense Innovation institute Academy of Military ScienceBeijing100071China

Due to the time-varying topology and possible disturbances in a conflict environment,it is still challenging to maintain the mission performance of flying Ad hoc networks(FANET),which limits the application of Unmanned Aerial Vehicle(uav)swarms in harsh *** paper proposes an intelligent framework to quickly recover the cooperative coveragemission by aggregating the historical spatio-temporal network with the attention *** mission resilience metric is introduced in conjunction with connectivity and coverage status information to simplify the optimization model.A spatio-temporal node pooling method is proposed to ensure all node location features can be updated after destruction by capturing the temporal network *** with the corresponding Laplacian matrix as the hyperparameter,a recovery algorithm based on the multi-head attention graph network is designed to achieve rapid *** results showed that the proposed framework can facilitate rapid recovery of the connectivity and coverage more effectively compared to the existing *** results demonstrate that the average connectivity and coverage results is improved by 17.92%and 16.96%,respectively compared with the state-of-the-art ***,by the ablation study,the contributions of each different improvement are *** proposed model can be used to support resilient network design for real-time mission execution.

关键词： Resilience cooperative mission FANET spatio-temporal node pooling multi-head attention graph network

Switchable shape memory polymer bio-inspired adhesive and its application for unmanned aerial vehicle landing

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Chinese Journal of Aeronautics 2024年第3期37卷 380-390页

作者： Qingsong HE Zefang ZHAO Qiyun ZHONG Siyuan LIU Kai DENG Yongqi LIU Ning ZHANG Zijie ZHAO Fengjiang ZHAN Jianfeng ZHAO Jiangsu Provincial Key Laboratory of Bionic Functional Materials College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Advanced Technology for Small and Medium-Sized uav Ministry of Industry and Information TechnologyUnmanned Aerial Vehicles Research InstituteNanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of Mechanics and Control of Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Functional Morphology and Biomechanics Institute of ZoologyKiel UniversityKiel 24098Germany

Controlled and switchable adhesion is commonly observed in biological *** recent years,many scholars have focused on making switchable bio-inspired ***,making a bio-inspired adhesive with high adhesion performance and excellent dynamic switching properties is still a challenge.A Shape Memory Polymer Bio-inspired Adhesive(SMPBA)was successfully developed,well realizing high adhesion(about 337 kPa),relatively low preload(about90 kPa),high adhesion-to-preload ratio(about 3.74),high switching ratio(about 6.74),and easy detachment,which are attributed to the controlled modulus and contact area by regulating temperature and the Shape Memory Effect(SME).Furthermore,SMPBA exhibits adhesion strength of80–337 kPa on various surfaces(silicon,iron,and aluminum)with different roughness(Ra=0.021–10.280)because of the conformal contact,reflecting outstanding surface *** finite element analysis verifies the bending ability under different temperatures,while the adhesion model analyzes the influence of preload on contact area and ***,an Unmanned Aerial Vehicle(uav)landing device with SMPBA was designed and manufactured to achieve uav landing on and detaching from various *** study provides a novel switchable bio-inspired adhesive and uav landing method.

关键词： Bio-inspired adhesive Shape memory polymers Switchable adhesive Unmanned aerial vehicle Landing

Numerical Simulation and Experiment on Thin-Shell Object Separation from Aircraft

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Transactions of Nanjing University of Aeronautics and Astronautics 2015年第1期32卷 89-96页

作者：梁世波王阳夏健 uav Research institute Nanjing University of Aeronautics and Astronautics

The unsteady aerodynamic loads generated by the thin-shell object separating from aircraft affects flying *** investigate the loads,a method combining numerical simulation and experiment is ***,the motional tendency of the thin-shell object separating from aircraft is calculated,and then the high-speed air blowing test on ground is ***,the external store is employed to avoid colliding with the thin-shell object in ***,the hanging and flight test is conducted by a high-speed unmanned aerial vehicle(uav),and the feasibility of the thin-shell object separating from aircraft at high speed is ***,the separating problem of a thin-shell object with an unconventional aerodynamic configuration is solved,and the collisions with aircraft is prevented.

关键词： external stores thin-shell object external stores separation unstructured overset grid

An adaptive 3D reconstruction method for asymmetric dual-angle multispectral stereo imaging system on uav platform

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Science China(Information Sciences) 2024年第8期67卷 285-299页

作者： Chen WANG Xian LI Yanfeng GU Zixu WANG School of Electronics and Information Engineering Harbin Institute of Technology Beijing institute of Control and Electronic Technology

A multispectral imaging system often cannot capture 3D spatial information owing to hardware limitations, which diminishes the effectiveness across various domains. To address this problem, we have developed a multispectral stereo imaging system along with an adaptive 3D reconstruction algorithm. Unlike existing unmanned aerial vehicle stereo imaging systems, our multispectral stereo imaging system uses two multispectral cameras with asymmetric spectral bands positioned at different angles. This design enables the acquisition of a higher number of bands and lateral spatial information while maintaining a lightweight structure. This system introduces challenges such as large geometric distortions and intensity differences between multiple bands. To accurately recover 3D spatial information, we propose an adaptive 3D reconstruction method. This method employs a position and orientation system-assisted projection transformation and a normalized threshold adjustment strategy. Finally, mutual information is used to reconstruct the multispectral images densely, effectively addressing nonlinear differences and generating a comprehensive multispectral point cloud. Our stereo system was used for two real data collections in different regions, and the efficacy of the proposed 3D reconstruction method was validated by comparing it with existing methods and commercial software.

关键词： multispectral images 3D reconstruction stereo imaging system unmanned aerial vehicle feature extraction

Absolute pose estimation of uav based on large-scale satellite image

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Chinese Journal of Aeronautics 2024年第6期37卷 219-231页

作者： Hanyu WANG Qiang SHEN Zilong DENG Xinyi CAO Xiaokang Wang School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Beijing institute of Technology Chongqing Innovation Center Chongqing 401120China

Obtaining absolute pose based on pre-loaded satellite images is one of the important means of autonomous navigation for small Unmanned Aerial Vehicles(uavs)in Global Navigation Satellite System(GNSS)denied *** of the previous works have tended to build Convolutional Neural Networks(CNNs)to extract features and then directly regress the pose,which will fail when solving the challenges caused by the huge viewpoint and size differences between“uav-satellite”image pairs in real-world ***,this paper proposes a probability distribution/regression integrated deep model with the attention-guided triple fusion mechanism,which estimates discrete distributions in pose space and three-dimensional vectors in translation *** order to overcome the shortage of the relevant dataset,this paper simulates image datasets captured by uavs with forward-facing cameras during target searching and autonomous *** effectiveness,superiority,and robustness of the proposed method are verified by simulated datasets and flight tests.

关键词： Satellite imagery Unmanned Aerial Vehicle(uav) Deep neural networks Vision navigation von Mises-Fisher distribution

Unstructured Road Extraction in uav Images based on Lightweight Model

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 372-384页

作者： Di Zhang Qichao An Xiaoxue Feng Ronghua Liu Jun Han Feng Pan School of Automation Beijing Institute of TechnologyBeijing 100081China Tianjin institute of Maritime Navigation Instruments Tianjin 300130China The 716th Research institute of China Shipbuilding Group Co. LtdJiangsu 222061China

There is no unified planning standard for unstructured roads,and the morphological structures of these roads are complex and *** is important to maintain a balance between accuracy and speed for unstructured road extraction *** road extraction algorithms based on deep learning have problems such as high model complexity,high computational cost,and the inability to adapt to current edge computing ***,it is best to use lightweight network *** the need for lightweight models and the characteristics of unstructured roads with different pattern shapes,such as blocks and strips,a TMB(Triple Multi-Block)feature extraction module is proposed,and the overall structure of the TMBNet network is *** TMB module was compared with SS-nbt,Non-bottleneck-1D,and other modules via *** feasibility and effectiveness of the TMB module design were proven through experiments and *** comparison experiment,using multiple convolution kernel categories,proved that the TMB module can improve the segmentation accuracy of the *** comparison with different semantic segmentation networks demonstrates that the TMBNet network has advantages in terms of unstructured road extraction.

关键词： Unstructured road Lightweight model Triple Multi-Block(TMB) Semantic segmentation net

Distributed collaborative complete coverage path planning based on hybrid strategy

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Journal of Systems Engineering and Electronics 2024年第2期35卷 463-472页

作者： ZHANG Jia DU Xin DONG Qichen XIN Bin School of Automation Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Autonomous Intelligent Unmanned Systems Beijing Institute of TechnologyBeijing 100081China

Collaborative coverage path planning(CCPP) refers to obtaining the shortest paths passing over all places except obstacles in a certain area or space. A multi-unmanned aerial vehicle(uav) collaborative CCPP algorithm is proposed for the urban rescue search or military search in outdoor *** to flexible control of small uavs, it can be considered that all uavs fly at the same altitude, that is, they perform search tasks on a two-dimensional plane. Based on the agents’ motion characteristics and environmental information, a mathematical model of CCPP problem is established. The minimum time for uavs to complete the CCPP is the objective function, and complete coverage constraint, no-fly constraint, collision avoidance constraint, and communication constraint are considered. Four motion strategies and two communication strategies are designed. Then a distributed CCPP algorithm is designed based on hybrid strategies. Simulation results compared with patternbased genetic algorithm(PBGA) and random search method show that the proposed method has stronger real-time performance and better scalability and can complete the complete CCPP task more efficiently and stably.

关键词： multi-agent cooperation unmanned aerial vehicles(uav) distributed algorithm complete coverage path planning(CCPP)

Transonic Rudder Buzz on Tailless Flying Wing uav

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Transactions of Nanjing University of Aeronautics and Astronautics 2015年第1期32卷 61-69页

作者：许军马晓平 College of Aeronautics Northwestern Polytechnical University uav Research institute Northwestern Polytechnical University

Transonic rudder buzz responses based on the computational fluid dynamics or computational structural dynamics(CFD/CSD)loosely method are analyzed for a tailless flying wing unmanned aerial vehicle(uav).The Reynolds-averaged Navier-Stokes(RANS)equations and finite element methods based on the detailed aerodynamic and structural model are established,in which the aerodynamic dynamic meshes adopt the unstructured dynamic meshes based on the combination of spring-based smoothing and local remeshing methods,and the lower-upper symmetric-Gauss-Seidel(LU-SGS)iteration and Harten-Lax-van Leer-Einfeldt-Wada(HLLEW)space discrete methods based on the shear stress transport(SST)turbulence model are used to calculate the aerodynamic *** constraints of the rudder motions are fixed at the end of structural model of the flying wing uav,and the structural geometric nonlinearities are also considered in the flying wing uav with a high aspect *** interfaces between structural and aerodynamic models are built with an exact match surface where load transferring is performed based on *** flying wing uav transonic buzz responses based on the aerodynamic structural coupling method are studied,and the rudder buzz responses and aileron,elevator and flap vibration responses caused by rudder motion are also *** effects of attack,height,rotating angular frequency and Mach number under transonic conditions on the flying wing uav rudder buzz responses are *** results can be regarded as a reference for the flying wing uav engineering vibration analysis.

关键词： flying wing unmanned aerial vehicle(uav) buzz CFD/CSD transonic flow geometric nonlinearities

New slant range model and azimuth perturbation resampling based high-squint maneuvering platform SAR imaging

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Journal of Systems Engineering and Electronics 2021年第3期32卷 545-558页

作者： XIONG Xuying LI Gen MA Yanheng CHU Lina institute of uav Engineering Army Engingeering UniversityShijiazhuang 050003China

Strong spatial variance of the imaging parameters and serious geometric distortion of the image are induced by the acceleration and vertical velocity in a high-squint synthetic aperture radar(SAR)mounted on maneuvering *** this paper,a frequency-domain imaging algorithm is proposed based on a novel slant range model and azimuth perturbation ***,a novel slant range model is presented for mitigating the geometric distortion according to the equal squint angle curve on the ground ***,the correction of azimuth-dependent range cell migration(RCM)is achieved by introducing a high-order time-domain perturbation ***,an azimuth perturbation resampling method is proposed for azimuth *** azimuth resampling and the time-domain perturbation are used for correcting first-order and high-order azimuthal spatial-variant components,*** results illustrate that the proposed algorithm can improve the focusing quality and the geometric distortion correction accuracy of the imaging scene effectively.

关键词： synthetic aperture radar(SAR)imaging maneuvering platform high-squint azimuth perturbation resampling