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Observer-based robust high-order fully actuated attitude autopilot design for spinning glide-guided projectiles

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Defence Technology（防务技术） 2024年第4期34卷 282-294页

作者： Wei Wang Yuchen Wang Shiwei Chen Yongcang Guo Zhongjiao Shi School of aerospace Engineering Beijing Institute of TechnologyBeijing 10081China Northwest Industries Group co. Ltd.Xi'an 710043China

This paper investigates the design of an attitude autopilot for a dual-channel co.trolled spinning glideguided projectile(SGGP),addressing model uncertainties and external *** on fixed-time stable theory,a disturbance observer with integral sliding mode and adaptive techniques is proposed to mitigate total disturbance effects,irrespective of initial *** introducing an error integral signal,the dynamics of the SGGP are transformed into two separate seco.d-order fully actuated ***,employing the high-order fully actuated approach and a parametric approach,the nonlinear dynamics of the SGGP are recast into a co.stant linear closed-loop system,ensuring that the projectile's attitude asymptotically tracks the given goal with the desired *** the proposed co.posite co.trol framework,the ultimately uniformly bounded stability of the closed-loop system is rigorously demonstrated via the Lyapunov *** of the effectiveness of the proposed attitude autopilot design is provided through extensive numerical simulations.

关键词： Spinning glide-guided projectile Attitude co.trol Sliding mode disturbance observer Fixed-time stable theory High-order fully actuated approach

Neural Network Robust co.trol Based on co.puted Torque for Lower Limb Exoskeleton

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 83-99页

作者： Yibo Han Hongtao Ma Yapeng Wang Di Shi Yanggang Feng Xianzhong Li Yanjun Shi Xilun Ding Wuxiang Zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Beihang Goer(WeiFang)Intelligent Robot co. Ltd.Beihang UniversityWeifangChina Research Center of Satellite Technology Harbin Institute of TechnologyHarbinChina Beijing Xinfeng aerospace Equipment co. LtdBeijingChina

The lower limb exoskeletons are used to assist wearers in various scenarios such as medical and industrial *** modeling errors of the exoskeleton in different application scenarios pose challenges to the robustness and stability of its co.trol *** Radial Basis Function(RBF)neural network is used widely to co.pensate for modeling *** order to solve the problem that the current RBF neural network co.trollers cannot guarantee the asymptotic stability,a neural network robust co.trol algorithm based on co.puted torque method is proposed in this paper,focusing on trajectory *** innovatively inco.porates the robust adaptive term while introducing the RBF neural network term,improving the co.pensation ability for modeling *** stability of the algorithm is proved by Lyapunov method,and the effectiveness of the robust adaptive term is verified by the *** wearing the exoskeleton under different walking speeds and scenarios were carried out,and the results show that the absolute value of tracking errors of the hip and knee joints of the exoskeleton are co.sistently less than 1.5°and 2.5°,*** proposed co.trol algorithm effectively co.pensates for modeling errors and exhibits high robustness.

关键词： Lower limb exoskeleton Model co.pensation RBF neural network co.puted torque method

co.mand filtered integrated estimation guidance and co.trol for strapdown missiles with circular field of view

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Defence Technology（防务技术） 2024年第5期35卷 211-221页

作者： Wei Wang Jiaqi Liu Shiyao Lin Baokui Geng Zhongjiao Shi School of aerospace Engineering Beijing Institute of TechnologyBeijing 10081China China Research and Development Academy of Machinery Equipment Beijing 100089China Northwest Industries Group co. Ltd.Xi'an 710043China

In this paper,an integrated estimation guidance and co.trol(IEGC)system is designed based on the co.mand filtered backstepping approach for circular field-of-view(FOV)strapdown *** threedimensional integrated estimation guidance and co.trol nonlinear model with limited actuator deflection angle is established co.sidering the seeker's FOV *** boundary time-varying integral barrier Lyapunov function(IBLF)is employed in backstepping design to co.strain the body line-of-sight(BLOS)in IEGC system to fit a circular ***,the nonlinear adaptive co.troller is designed to estimate the changing aerodynamic *** generalized extended state observer(GESO)is designed to estimate the acceleration of the maneuvering targets and the unmatched time-varying disturbances for improving tracking ***,the co.mand filters are used to solve the"differential expansion"problem during the backstepping *** Lyapunov theory is used to prove the stability of the overall closed-loop IEGC ***,the simulation results validate the integrated system's effectiveness,achieving high accuracy strikes against maneuvering targets.

关键词： Integrated estimation guidance and co.trol Circular field-of-view Time-varying integral barrier Lyapunov function co.mand filtered backstepping co.trol Nonlinear adaptive co.trol Extended state observer

State of the art in movement around a remote point:a review of remote center of motion in robotics

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Frontiers of Mechanical Engineering 2024年第2期19卷 1-28页

作者： Wuxiang ZHANG Zhi WANG Ke MA Fei LIU Pengzhi CHENG Xilun DING School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Ningbo Institute of Technology Beihang UniversityNingbo 315832China Intelligent aerospace Manufacturing Engineering Technology co. Ltd.Beijing 100191China

The co.cept of remote center of motion(RCM)is pivotal in a myriad of robotic applications,enco.pa-ssing areas such as medical robotics,orientation devices,and exoskeletal *** efficacy of RCM technology is a determining factor in the success of these robotic *** paper offers an exhaustive review of RCM technologies,elaborating on their various methodologies and practical *** delves into the unique characteristics of RCM across different degrees of freedom(DOFs),aiming to distill their fundamental *** addition,this paper categorizes RCM approaches into two primary classifications:design based and co.trol *** are further organized acco.ding to their respective DOFs,providing a co.cise summary of their co.e *** upon the understanding of RCM’s versatile capabilities,this paper then transitions to an in-depth exploration of its applications across diverse robotic *** this review,we critically analyze the existing research challenges and issues that are inherently present in both RCM methodologies and their *** discussion is intended to serve as a guiding framework for future research endeavors and practical deployments in related areas.

关键词： remote center of motion mechanism robotics medical robot orientation device exoskeleton

Synthesis of multifunctional additives for solid propellants:Structure,properties and mechanism

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Defence Technology（防务技术） 2024年第3期33卷 308-316页

作者： Pingan Zhang Lina Sun Jianmin Yuan Jianru Deng co.lege of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082PR China co.lege of Material Science and Engineering Hunan UniversityChangsha 410082PR China Hu Bei Sanjiang aerospace Jianghe Chemical Technology co. LtdYichang 444200PR China

To simplify the co.posite propellant formulation and address the current issue of the single-functionality present in existing additives,the multi-cyano,amine-based polybutadiene(AEHTPB-CN)was prepared based on AEHTPB by adopting appropriate synthesis *** replacing 10% of HTPB binder in the propellant formulation,it can effectively enhance the interfacial bond strength between the propellant binder matrix and solid fillers(AP(ammonium perchlorate)and RDX(cyclotrimethylene-trinitramine)),the mechanical properties of the HTPB/AP/RDX/Al propellant were superior to blank co.trol propellant with an improvement of 35.4% in tensile strength,62.0% enhancement in elongation at break,and reduce the propellant burn rate by 10.7% with any energy *** function mechanism of AEHTPB-CN was systematically elucidated through experiments and co.puter simulation *** results show that the tertiary amine group in AEHTPB-CN can react with AP to form ammonium ionic bonds,and the hydroxyl and cyano groups can form hydrogen bonding interactions with AP,which enables AEHTPB-CN to be firmly adsorbed on the AP surface through chemical and physical *** RDX,the interfacial bonding effect of AEHTPB-CN is attributed to their ability to form C-H···N≡C weak hydrogen bonding interaction between the cyano group and RDX methylene group.

关键词： Hydroxyl-terminated polybutadiene(HTPB) HTPB propellant Chemical modification Bonding agent Mechanism

Skin-inspired interface modification strategy toward a structurefunction integrated hybrid smart fabric system with self-powered sensing property for versatile applications

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Nano Research 2024年第9期17卷 8200-8208页

作者： Xiang Cheng Teng Chen De Gong Pengcheng Ma Bo Chen Jun Cai aerospace Information Research Institute Chinese Academy of SciencesBeijing 100190China School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Beijing U-Precision Tech co. Ltd.Beijing 100176China University of Chinese Academy of Sciences Beijing 100049China

Fabric-based co.posites with superior mechanical properties and excellent perceptive function are highly ***,it remains a huge challenge to attain structure-function integration,especially for hybrid fabric ***,a skin-inspired interface modification strategy is proposed toward this target by co.structing a hybrid smart fabric system co.sisting of two types of smart fabrics:carbon nanotube(CNT)/MXene-modified aramid fabrics and zinc oxide nanorod(ZnO NR)-modified carbon *** on that,flexible piezoelectric pressure sensors with skin-like hierarchical perception interfaces are fabricated,which demonstrate superb sensitivity of 2.39 V·kPa^(-1)and are capable of various wearable monitoring ***,the interface-modified hybrid fabric reinforced plastics can also be fabricated,which are proven to possess 13.6%higher tensile strength,10.1%elastic *** impressively,their average energy absorption can be improved by 111.9%,acco.panied with inherent damage alert *** offers a paradigm to fabricate structure-function integrated hybrid smart fabric co.posites for the smart clothing and intelligent aerial vehicles.

关键词： hybrid fabrics interface modification piezoelectric pressure sensors self-diagnostic co.posites structure-function integration

Real-Time Monitoring Method for co. Rumination Behav‐ior Based on Edge co.puting and Improved MobileNet v3

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智慧农业（中英文） 2024年第4期6卷 29-41页

作者： ZHANG Yu LI Xiangting SUN Yalin XUE Aidi ZHANG Yi JIANG Hailong SHEN Weizheng co.lege of Electrical and Information Northeast Agricultural UniversityHarbin 150030China Harbin aerospace Stellar Data System Technology co. LtdHarbin 150030China Harbin Electric Machinery co.pany co. Ltd.Harbin 150030China

[Objective]Real-time monitoring of co. ruminant behavior is of paramount importance for promptly obtaining relevant information about co. health and predicting co. ***,various strategies have been proposed for monitoring co. ruminant behavior,including video surveillance,sound reco.nition,and sensor monitoring ***‐ever,the application of edge device gives rise to the issue of inadequate real-time *** reduce the volume of data transmission and cloud co.puting workload while achieving real-time monitoring of dairy co. rumination behavior,a real-time monitoring method was proposed for co. ruminant behavior based on edge co.puting.[Methods]Autono‐mously designed edge devices were utilized to co.lect and process six-axis acceleration signals from co.s in *** on these six-axis data,two distinct strategies,federated edge intelligence and split edge intelligence,were investigat‐ed for the real-time reco.nition of co. ruminant *** on the real-time reco.nition method for co. ruminant behavior leveraging federated edge intelligence,the CA-MobileNet v3 network was proposed by enhancing the MobileNet v3 network with a co.laborative attention ***,a federated edge intelligence model was designed uti‐lizing the CA-MobileNet v3 network and the FedAvg federated aggregation *** the study on split edge intelli‐gence,a split edge intelligence model named MobileNet-LSTM was designed by integrating the MobileNet v3 network with a fusion co.laborative attention mechanism and the Bi-LSTM network.[Results and Discussions]Through co.para‐tive experiments with MobileNet v3 and MobileNet-LSTM,the federated edge intelligence model based on CA-Mo‐bileNet v3 achieved an average Precision rate,Recall rate,F1-Sco.e,Specificity,and Accuracy of 97.1%,97.9%,97.5%,98.3%,and 98.2%,respectively,yielding the best reco.nition performance.[co.clusions]It is provided a real-time and effective method for monitoring co. rumin

关键词： co. rumination behavior real-time monitoring edge co.puting improved MobileNet v3 edge intelligence model Bi-LSTM

Sandwich structures with tapered tubes as co.e:A quasi-static investigation

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Defence Technology（防务技术） 2024年第3期33卷 447-462页

作者： Xinmei Xiang Dehua Shao Xin Zhang Umer Sharif Ngoc San Ha Li Xiang Jing Zhang Jiang Yi School of Civil Engineering Guangzhou UniversityGuangzhouChina Department of Mechanics and aerospace Engineering Southern University of Science and TechnologyShenzhenGuangdongChina School of Engineering Centre for Innovative Structures and MaterialsRMIT UniversityMelbourneAustralia China Southern Airlines co. LtdShenzhen BranchShenzhen518000China

In this article,the experimental and finite element analysis is utilized to investigate the quasi-static co.pression features of sandwich co.structions built with tapered tubes.3D printing technology was utilized to create the hollow centers of the tapering tubes,with and without *** results demonstrate that the energy absorption(EA)and specific energy absorption(SEA)of the single co.rugated tapered tube sandwich are 51.6% and 19.8% higher,respectively,than those of the co.ical tube ***,the results demonstrate that energy absorbers can benefit from co.rugation in order to increase their ***,the tapered co.rugated tubes'resistance to oblique impacts was *** to a straight tube,the tapered tube is more resistant to oblique loads and has a lower initial peak crushing force(PCF),acco.ding to numerical *** co.ducting a parametric study,it was disco.ered that the energy absorption performance of the sandwich co.struction is significantly affected by the amplitude,number of co.rugations,and wall *** and SEA of DTS with co.rugation number of 8 increased by 17.4%and 29.6%,respectively,while PCF decreased by 9.2% co.pared to DTS with co.rugation number of 10.

关键词： Sandwich structure co.rugated tube Tapered tube Quasi-static Energy absorption

Ultrathin polyimide-based co.posites with efficient low-reflectivity electromagnetic shielding and infrared stealth performance

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Nano Research 2024年第7期17卷 6700-6712页

作者： Xu Zhao Xinwei Tang Yunlong Qiao Shuangshuang Li Zihang Zhang Yezi Lu Mingyang Zhu Zaiyin Hu Lijuan Long Zicheng Wang Tianxi Liu The Key Laboratory of Synthetic and Biological co.loids Ministry of EducationSchool of Chemical and Material EngineeringInternational Joint Research Laboratory for Nano Energy CompositesJiangnan UniversityWuxi 214122China Guizhou aerospace Wujiang Electro-mechanical Equipment co. Ltd.No.20-5Dalian Road Aerospace Industrial ParkHuichuan DistrictZunyi 563000China School of Materials and Architectural Engineering Guizhou Normal UniversityGuiyang 550025China

Researching and manufacturing materials that possess both electromagnetic interference(EMI)shielding and infrared stealth capabilities is of great ***,an ultrathin polyimide-based nonwoven fabric with low-reflection EMI shielding/infrared stealth performance is successfully fabricated by in-situ loading of Fe3O4/Ag nanoparticles on the surface of polyimide(PI)fiber(PFA),and followed by bonding with a co.mercial Cu/Ni *** synergistic assembly of PFA and Cu/Ni promotes the rational co.struction of hierarchical impedance matching,inducing electromagnetic waves(EMW)to enter the co.posite and be dissipated as much as ***,the existence of Cu/Ni mesh on back of PFA facilitates the formation of electromagnetic resonance and destructive interference of EMW reflected from co.posite,leading to a lowerreflectivity(0.26)EMI shielding performance of 58 dB within 24–40 GHz at a thinner thickness(430μm).More importantly,the fluffy PFA nonwoven fabric and metal Cu/Ni mesh endow co.posite with good thermal insulation and low infrared emissivity,resulting in excellent infrared stealth performance in various *** a result,such excellent co.patibility makes it possible to beco.e a promising defense material to be applied in military tent for preventing electromagnetic and infrared radiation.

关键词： polyimide electromagnetic interference shielding low reflection infrared stealth