检索结果-南通市图书馆

Observer design and interval estimation of time-delay discrete-time linear systems with external disturbance and measurement noise

在线全文

学校读者我要写书评

暂无评论

Control Theory and Technology 2024年第1期22卷 69-80页

作者： Junqi Yang Jianhao Xie Feiyang Liu School of Electrical Engineering and automation Henan Key Laboratory of Intelligent Detection and Control of Coal Mine EquipmentHenan Polytechnic UniversityJiaozuo454003HenanChina

For a class of time-delay discrete-time linear systems with external disturbance and measurement noise, the interval estimation problems of state and measurement noise are investigated in this paper. First, the system state together with the time-delay term and measurement noise is augmented as a new state, and a singular system is then constructed. Subsequently, a kind of decoupling technique is employed to eliminate the effect of external disturbance, and an observer is designed to simultaneously estimate the system state and measurement noise. Based on the estimated state and measurement noise, the interval estimations of system state and measurement noise are obtained by reachability analysis technique. Finally, the effectiveness of the proposed method is verified by a four-tank liquid level system.

关键词： Interval estimation Time-delay system Observer design Reachability analysis

New Results in Cooperative Adaptive Optimal Output Regulation

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

Journal of Systems Science & Complexity 2024年第1期37卷 253-272页

作者： DONG Yuchen GAO Weinan JIANG Zhong-Ping state key laboratory of Synthetical automation for Process Industries Northeastern UniversityShenyang 110819China Department of Electrical and Computer Engineering Tandon School of EngineeringNew York UniversityBrooklynNY 11201USA

This paper investigates the cooperative adaptive optimal output regulation problem of continuous-time linear multi-agent systems.As the multi-agent system dynamics are uncertain,solving regulator equations and the corresponding algebraic Riccati equations is challenging,especially for high-order systems.In this paper,a novel method is proposed to approximate the solution of regulator equations,i.e.,gradient descent method.It is worth noting that this method obtains gradients through online data rather than model information.A data-driven distributed adaptive suboptimal controller is developed by adaptive dynamic programming,so that each follower can achieve asymptotic tracking and disturbance rejection.Finally,the effectiveness of the proposed control method is validated by simulations.

关键词： Adaptive dynamic programming cooperative output regulation gradient descent method multi-agent systems.

Vision-based docking system for an aromatic-hydrocarbon-inspired reconfigurable robot

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第6期67卷 1798-1816页

作者： XING FangYi XU Cheng LIU JinGuo XUE ZhiHui state key laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang110016China School of automation and Electrical Engineering Shenyang Ligong UniversityShenyang110158China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang110169China University of Chinese Academy of Sciences Beijing100049China

Aromatic hydrocarbons generally refer to compounds containing benzene rings.Many types of isomers can be formed by replacing hydrogen atoms on the benzene ring.In this paper,an aromatic-hydrocarbon-inspired modular robot(AHIMR)is proposed.The robot can be reassembled into different configurations suitable for various task requirements.A vision-based docking system is designed for the AHIMR.The system primarily consists of two stages:a remote guidance stage and a precise docking stage.During the remote guidance stage,an object module is identified using an illumination adaptive target recognition algorithm,and then the active module moves to the docking area through communication with ZigBee.In the precise docking stage,the active module calculates the relative pose with the object module using a perspective-n-point method and dynamically adjusts its posture to dock.In this process,a Kalman filter is used to reduce target occlusion and jitter interference.In addition,the docking system feasibility is verified via several simulation experiments.The module docking accuracy is controlled within 0.01 m,which meets the reconfiguration task requirements of the AHIMR.In the AHIMR submodule docking experiment,the active module accurately moves to the expected position with a docking success rate of 95%.

关键词： modular robot reconfiguration aromatic hydrocarbon autonomous docking visual identification

Object Helps U-Net Based Change Detectors

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2期11卷 548-550页

作者： Lan Yan Qiang Li Kenli Li College of Computer Science and Electronic Engineering Hunan UniversityChangsha 410082China state key laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China

Dear Editor,This letter focuses on leveraging the object information in images to improve the performance of the U-Net based change detector.Change detection is fundamental to many computer vision tasks.Although exist... 详细信息

关键词： Net computer networks

Parallel Light Fields: A Perspective and A Framework

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2期11卷 542-544页

作者： Fei-Yue Wang Yu Shen IEEE state key laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China School of Artificial Intelligence University of Chinese Academy of ScienceBeijing 100049

Dear Editor,Light fields give relatively complete description of scenes from perspective of angles and positions of rays. At present time, most of the computer vision algorithms take 2D images as input which are simplified expression of light fields with depth information discarded. In theory, computer vision tasks may achieve better performance as long as complete light fields are acquired.

关键词： computer Framework simplified

Prescribed Performance Tracking Control of Time-Delay Nonlinear Systems With Output Constraints

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7期11卷 1557-1565页

作者： Jin-Xi Zhang Kai-Di Xu Qing-Guo Wang IEEE the state key laboratory of Synthetical automation for Process Industries Northeastern UniversityShenyang 110819China Institute of Artificial Intelligence and Future Networks Beijing Normal UniversityZhuhai 519087 Guangdong key laboratory of Artificial Intelligence and Multi-Modal Data Processing Beijing Normal University-Hong Kong Baptist University United International CollegeZhuhai 519087

The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this paper.Herein, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings.

关键词： Nonlinear systems output constraints prescribed performance reference tracking time delays

A flat-foldable equiangular spiral folding pattern inspired by sunflowers for deployable structures

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

Chinese Journal of Aeronautics 2024年第6期37卷 425-438页

作者： Shuangqing YU Jinguo LIU Pengyuan ZHAO Yingying TANG state key laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China University of Chinese Academy of Sciences Beijing 100049China

Flasher origami pattern has been widely utilized to improve the stowage efficiency of deployable structures.Nevertheless,flasher origami cannot be folded fully flat,and they still have great potential for optimization in terms of storage volume and folding creases.In this paper,a flat foldable equiangular spiral folding pattern inspired by the sunflower disk is introduced.Then,a parametric design method for this equiangular spiral crease diagram is introduced in detail.Subsequently,a kinematic model of the equiangular spiral folding pattern is established based on the kinematic equivalence between rigid origami and spherical linkages.A simulation of the developed model demonstrates that the equiangular spiral folding pattern can be folded flat.Using the folded ratio as an evaluation index,the calculated results and experiments show that the equiangular spiral crease pattern can yield fewer creases and improve stowage efficiency in comparison to flasher origami pattern.Equiangular spiral folding pattern can save a considerable amount of space and provide a new approach to spatially deployable structures.

关键词： Flasher origami Sunflower-inspired Deployable structures Flat-foldability Equiangular spiral folding pattern

Study on the tribological properties of metal rolling bearing under lubrication with diketone lubricants

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

Science China Technological Sciences 2024年第7期67卷 2003-2017页

作者： DU ShaoNan ZHANG ChenHui LUO Zhi state key laboratory of Tribology in Advanced Equipment Tsinghua University Beijing National laboratory of Molecular Sciences CAS Key Laboratory of Engineering Plastics Institute of Chemistry Chinese Academy of Sciences

In this article, 1-(4-ethylphenyl)-nonane-1,3-dione(0206) was prepared by Claisen condensation. By mixing 0206, chelate, and base oil in a ratio of 3.2:4.8:2, a diketone lubricant(PAO=14(20%)) that can achieve superlubricity was prepared and applied to bearing lubrication experiments. The experimental results show that when the bearing was lubricated by base oil, the friction coefficient(COF) and temperature rise decreased with the decrease of the viscosity of PAO. When PAO=14(20%) was used as the lubricant, the COF of the bearing was the lowest(0.001), and the wear morphology was comparable to that of the bearing lubricated with commercial lubricant. Compared with the base oil with the same viscosity, it is found that the COF and temperature rise of the bearing lubricated by PAO=14(20%) were lower under any experimental conditions. And when the amount of lubricant added was 10 μL, the COF of the bearing lubricated by PAO=14(20%) reached a very low value(0.0004).Bearing ball surface analysis identified the formation of diketone adsorption films. Combined with the previous PAO=14(20%)superlubricity mechanism, it was considered that the occurrence of tribochemical reaction and the bearing effect of chelates were the main reasons for the existence of ultra-low friction coefficient and low wear. In addition, when there were polar molecules in the lubricant, they were adsorbed on the metal surface through tribochemical reactions, resulting in many irregular pits on the surface.

关键词： superlubricity diketone chelate tribochemical recations, bearing lubrication

Towards resilient average consensus in multi-agent systems:a detection and compensation approach

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2期25卷 182-196页

作者： Chongrong FANG Wenzhe ZHENG Zhiyu HE Jianping HE Chengcheng ZHAO Jingpei WANG Department of automation Shanghai Jiao Tong UniversityShanghai200240China state key laboratory of Industrial Control Technology Zhejiang UniversityHangzhou310027China Technology and Engineering Center for Space Utilization Chinese Academy of SciencesBeijing100094China

Consensus is one of the fundamental distributed control technologies for collaboration in multi-agent systems such as collaborative handling in intelligent manufacturing.In this paper,we study the problem of resilient average consensus for multi-agent systems with misbehaving nodes.To protect consensus value from being influenced by misbehaving nodes,we address this problem by detecting misbehaviors,mitigating the corresponding adverse impact,and achieving the resilient average consensus.General types of misbehaviors are considered,including attacks,accidental faults,and link failures.We characterize the adverse impact of misbehaving nodes in a distributed manner via two-hop communication information and develop a deterministic detection compensation based consensus(D-DCC)algorithm with a decaying fault-tolerant error bound.Considering scenarios wherein information sets are intermittently available due to link failures,a stochastic extension named stochastic detection compensation based consensus(S-DCC)algorithm is proposed.We prove that D-DCC and S-DCC allow nodes to asymptotically achieve resilient accurate average consensus and unbiased resilient average consensus in a statistical sense,respectively.Then,the Wasserstein distance is introduced to analyze the accuracy of S-DCC.Finally,extensive simulations are conducted to verify the effectiveness of the proposed algorithms.

关键词： Resilient consensus Multi-agent systems Malicious attacks Detection Compensation