检索结果-南通市图书馆

Prescribed-time leader-following consensus of linear multi-agent systems by bounded linear time-varying protocols

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第1期67卷 140-153页

作者： Kai ZHANG Bin ZHOU Xuefei YANG Guangren DUAN Center for control Theory and guidance Technology Harbin Institute of Technology

This paper considers the prescribed-time leader-following consensus problem of input-constrained linear multi-agent systems under generally directed communication topology in two cases:the Laplacian matrix related to the entire communication topology between agents is either known or unknown.In particular,the consensus problem for the former case is solved by a novel bounded linear time-varying(LTV) protocol,where the feedback gain is formulated by the parametric Lyapunov equation and the knowledge of the Laplacian matrix.Moreover,by utilizing a distributed observer,a fully bounded LTV protocol is proposed for the latter case.It should be noted that,compared with the existing results,the system under consideration is more general,the designed protocols are linear,and the consensus problem is accomplished even in a fully distributed manner.Finally,the effectiveness of the proposed approach is verified by a numerical example.

关键词： leader-following consensus time-vary feedback prescribed-time control fully distributed consensus

A FAS approach for stabilization of generalized chained forms: part 1. Discontinuous control laws

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第2期67卷 118-143页

作者： Guang-Ren DUAN Center for control Theory and guidance Technology Harbin Institute of Technology Center for control Science and Technology Southern University of Science and Technology

In this paper, a type of general nonholonomic systems is proposed, which contains both the Brockett’s two example systems, and their extended n-dimensional chained forms, as special cases. For the stabilization of such systems, a stabilizing controller is proposed based on the fully actuated system(FAS)approach, which is discontinuous at the origin but time-invariant when the open-loop system is time-invariant,and drives the feasible trajectories of the system to the origin exponentially. Furthermore, the proposed FAS approach is also extended to the sub-normal system case and the time-delay system case.

关键词： nonholonomic systems feedback stabilization exponential convergence sub-fully actuated systems time-delay systems

A FAS approach for stabilization of generalized chained forms: part 2. Continuous control laws

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第3期67卷 114-135页

作者： Guang-Ren DUAN Center for control Theory and guidance Technology Harbin Institute of Technology Shenzhen Key Laboratory of control Theory and Intelligent Systems Southern University of Science and Technology

In this paper, continuous time-varying stabilizing controllers for the type of general nonholonomic systems proposed and treated in part 1 are designed using the fully actuated system(FAS) approach. The key step is to differentiate the first scalar equation, and by control of the obtained second-order scalar system, a proportional plus integral feedback form for the first control variable is obtained. With the solution to this designed second-order scalar system, the rest equations in the nonholonomic system form an independent time-varying subsystem which is then handled by the FAS approach. The overall designed controller contains an almost arbitrarily chosen design parameter, and is proven to guarantee the uniformly and globally exponential stability of the closed-loop system. The proposed approach is simple and effective,and is demonstrated with a practical example of ship control.

关键词： nonholonomic systems feedback stabilization fully actuated systems Lyapunov stability continuous controllers

Disturbance Observer-Based Predictive Tracking control of Uncertain HOFA Cyber-Physical Systems

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1711-1713页

作者： Da-Wei Zhang Guo-Ping Liu IEEE the Center for control Theory and guidance Technology Harbin Institute of TechnologyHarbin 150001China the Center for control Science and Technology Southern University of Science and TechnologyShenzhen 518055China

Dear Editor,In this letter,an output tracking control problem of uncertain cyber-physical systems(CPSs)is considered in the perspective of high-order fully actuated(HOFA)system theory,where a lumped disturbance is use... 详细信息

关键词： Observer Uncertain letter

维普期刊数据库博看期刊

Stabilization controller of An Extended Chained Nonholonomic System With Disturbance:An FAS Approach

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1262-1273页

作者： Zhongcai Zhang Guangren Duan School of Engineering Qufu Normal UniversityRizhao 276826China Center for control Science and Technology Southern University of Science and TechnologyShenzhen 518055 Center for control Theory and guidance Technology Harbin Institute of TechnologyHarbin 150001China

This study examines the stabilization issue of extended chained nonholonomic systems(ECNSs)with external disturbance.Unlike the existing approaches,we transform the considered system into a fully actuated system(FAS)model,simplifying the stabilizing controller design.We implement a separate controller design and propose exponential stabilization controller and finite-time stabilization controller under finite-time disturbance observer(FTDO)for the two system inputs.In addition,we discuss the specifics of global stabilization control design.Our approach demonstrates that two system states exponentially or asymptotically converge to zero under the provided switching stabilization control strategy,while all other system states converge to zero within a finite time.

关键词： design stabilization system

Sampling-efficient path planning and improved actor-critic-based obstacle avoidance for autonomous robots

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第5期67卷 197-214页

作者： Yefeng YANG Tao HUANG Tianqi WANG Wenyu YANG Han CHEN Boyang LI Chih-yung WEN Department of Aeronautical and Aviation Engineering The Hong Kong Polytechnic University Center for control Theory and guidance Technology Harbin Institute of Technology School of Engineering The University of Newcastle Research Center for Unmanned Autonomous Systems The Hong Kong Polytechnic University

Autonomous robots have garnered extensive utilization in diverse fields. Among the critical concerns for autonomous systems, path planning holds paramount importance. Notwithstanding considerable efforts in its development over the years, path planning for autonomous systems continues to grapple with challenges related to low planning efficiency and inadequate obstacle avoidance response in a timely manner.This study proposes a novel and systematic solution to the path planning problem within intricate office buildings. The solution consists of a global planner and a local planner. To handle the global planning aspect, an adaptive clustering-based dynamic programming rapidly exploring random tree(ACDP-RRT) algorithm is proposed. ACDP-RRT effectively identifies obstacles on the map by leveraging geometric features.These obstacles are then represented as a collection of sequentially arranged convex polygons, optimizing the sampling region and significantly enhancing sampling efficiency. For local planning, a network decoupling actor-critic(ND-AC) algorithm is employed. The proposed ND-AC simplifies the local planner design process by integrating planning and control loops into a neural network(NN) trained via an end-to-end model-free deep reinforcement learning(DRL) framework. Moreover, the adoption of network decoupling(ND) techniques leads to an improved obstacle avoidance success rate when compared to conventional actor-critic(AC)-based methods. Extensive simulations and experiments are conducted to demonstrate the effectiveness and robustness of the proposed approach.

关键词： rapidly exploring random tree (RRT) adaptive clustering network decoupling actor critic (AC) path planning

Vibration harmonic suppression technology for electromagnetic vibrators based on an improved sensorless feedback control method

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 472-483页

作者： Wei LI Junning CUI Xingyuan BIAN Limin ZOU Centerof Ultra-precision Optoelectronic Instrument Engineering Harbin Institute of TechnoogyHarbin 0080China Key Lab of Ultra-precision Intlligent Instrumentation(Harbin institute of Technology).Ministry of Industry and Information Technology Harbin 150080China

To realize low harmonic distortion of the vibration waveform output from electromagnetic vibrators,we propose a vibration harmonic suppression technology based on an improved sensorless feedback control method.Without changing the original driving circuit,the alternating current(AC)equivalent resistance of the driving coil is used to obtain high-precision vibration velocity information,and then a simple and reliable velocity feedback control system is established.Through the study of the effect of different values of key parameters on the system,we have achieved an effective expansion of the velocity characteristic frequency band of low-frequency vibration,resulting in an enhanced harmonic suppression capability of velocity feedback control.We present extensive experiments to prove the effectiveness of the proposed method and make comparisons with conventional control methods.In the frequency range of 0.01-1.00 Hz,without using any sensors,the method proposed in this study can reduce the harmonic distortion of the vibration waveform by about 40%compared to open-loop control and by about 20%compared to a conventional sensorless feedback control method.

关键词： Vibration calibration Electromagnetic vibrators Harmonic suppression Sensorless control method Velocity feedback control

维普期刊数据库

Epidemiological Characteristics of Human Parainfluenza Viruses Infections-China,2019-2023

在线全文

学校读者我要写书评

暂无评论

China CDC weekly 2024年第12期6卷 235-241,I0003,I0004页

作者： Yixuan Gao Yingwei Ma Daxing Feng Feng Zhang Biao Wang Xiaoqing Liu Bing Zhu Hui Xie Linqing Zhao Xiaoru Long Ying Chen Bing Wang Jie Jiang Zhen Zhu Yan Zhang Aili Cui Baicheng Xia Naiying Mao National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina precision Medicine Research Center Children’s Hospital of ChangchunChangchun CityJilin ProvinceChina Henan Provincial Center for Disease control and Prevention Zhengzhou CityHenan ProvinceChina Laboratory of Viral Diseases Qingdao Municipal Centre for Disease Control and PreventionQingdao CityShandong ProvinceChina Virus Laboratory Gansu Provincial Center for Disease Control and PreventionLanzhou CityGansu ProvinceChina Jiangxi Provincial Center for Disease control and Prevention Nanchang CityGansu ProvinceChina Virus Laboratory Guangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangzhou CityGuangdong ProvinceChina institute for Immunization and Prevention Beijing Center for Disease Prevention and ControlAcademy for Preventive MedicineInstitute of Tuberculosis Control Research and PreventionBeijingChina Laboratory of Virology Beijing Key Laboratory of Etiology of Viral Diseases in ChildrenCapital Institute of PediatricsBeijingChina Department of Infection Children’s Hospital of Chongqing Medical UniversityChongqingChina Inner Mongolia Autonomous Region Comprehensive Center for Disease control and Prevention Hohhot CityInner Mongolia Autonomous RegionChina Shenyang Prefecture Center for Disease control and Prevention Shenyang CityLiaoning ProvinceChina

Introduction:A retrospective study based on sentinel surveillance was conducted in 10 provinciallevel administrative divisions(PLADs)in China to enhance the understanding of the epidemiological characteristics of human parainfluenza viruses(HPIVs).Methods:From January 2019 to June 2023,respiratory specimens were collected from individuals with acute respiratory infections(ARIs)and screened for four HPIVs serotypes and other common respiratory viruses using multiplex real-time polymerase chain reaction(PCR).This study analyzed the association of HPIVs infections with seasonal patterns,geographical distribution,demographic profiles,clinical features,and co-infection status.Results:During the study period,a total of 12,866 ARIs were included.The overall detection rate of HPIVs was 6.15%,varying from 5.04%in 2022 to 9.70%in 2020.The median age of HPIVs-infected patients was 3 years.HPIV2 was more prevalent among individuals aged 5–17 years(42.57%),while HPIV4 was more common in those over 65 years(12.24%).HPIV3(54.16%)and HPIV1(27.18%)were the predominant serotypes,and their prevalence exhibited significant seasonal fluctuations postcoronavirus disease 2019(COVID-19)pandemic.The peak of HPIV3 shifted three months later in 2020 compared to 2019 and returned to a summer peak thereafter.Two peaks of HPIV1 were observed in 2021 following the peak of HPIV3.Additionally,coinfections were frequent in HPIVs cases(overall rate:22.12%),with human rhinovirus being the most common co-infecting virus.Conclusions:The prevalence of HPIVs in China was predominantly due to HPIV3 and HPIV1,and their seasonal patterns were altered by pandemic restrictions.Hence,continuous surveillance of HPIVs is essential.

关键词： prevalence seasonal Human

A low-frequency pure metal metamaterial absorber with continuously tunable stiffness

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1209-1224页

作者： Xingzhong WANG Shiteng RUI Shaokun YANG Weiquan ZHANG Fuyin MA School of Mechanical Engineering Xi'an Jiaotong University Xi'an precision Machinery Research institute

To address the incompatibility between high environmental adaptability and deep subwavelength characteristics in conventional local resonance metamaterials,and overcome the deficiencies in the stability of existing active control techniques for band gaps, this paper proposes a design method of pure metal vibration damping metamaterial with continuously tunable stiffness for wideband elastic wave absorption. We design a dual-helix narrow-slit pure metal metamaterial unit, which possesses the triple advantage of high spatial compactness, low stiffness characteristics, and high structural stability, enabling the opening of elastic flexural band gaps in the low-frequency range.Similar to the principle of a sliding rheostat, the introduction of continuously sliding plug-ins into the helical slits enables the continuous variation of the stiffness of the metamaterial unit, achieving a continuously tunable band gap effect. This successfully extends the effective band gap by more than ten times. The experimental results indicate that this metamaterial unit can be used as an additional vibration absorber to absorb the low-frequency vibration energy effectively. Furthermore, it advances the metamaterial absorbers from a purely passive narrowband design to a wideband tunable one. The pure metal double-helix metamaterials retain the subwavelength properties of metamaterials and are suitable for deployment in harsh environments. Simultaneously, by adjusting its stiffness, it substantially broadens the effective band gap range, presenting promising potential applications in various mechanical equipment operating under adverse conditions.

关键词： elastic metamaterial absorber continuously tunable stiffness low-frequency vibration damping variable stiffness design pure metal structure O343 74G60