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Chinese automation Congress (CAC)

作者： Zhongding Zhang Zeyu Guo Zuo Wang Shihua Li School of Automation Southeast University Nanjing China Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of Education Nanjing China Shenzhen Research Institute Southeast University Shenzhen China

Converter-driven motor systems play crucial roles in contemporary industrial applications owning to the advantages of smooth starting and stepless speed regulation. For such fourth-order systems with both immeasurable states and mismatched disturbances, a finite-time control solution is proposed to address the speed tracking problem in this paper. Firstly, a finite-time observer is constructed to precisely estimate the immeasurable states and mismatched disturbances. Then, based on integral terminal sliding mode control (ITSMC), a continuous finite-time controller is designed for the systems to achieve both rapid response and superior speed tracking performance. Furthermore, a rigorous global finite-time stability analysis for the closed-loop system is presented. Finally, simulation results validate the effectiveness of the proposed control method. As compared with existing methods, the composite ITSMC algorithm design demonstrates reliable finite-time speed tracking performance and exceptional capability in disturbance rejection.

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A Novel Visual Perception Framework for Unmanned Aerial Vehicles: Challenges and Approaches

A Novel Visual Perception Framework for Unmanned Aerial Vehi...

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2021 China automation Congress, CAC 2021

作者： Li, Xuan Duan, Haibin Mo, Hong Wang, Fei-Yue Department of Mathematics and Theories Peng Cheng Laboratory Shenzhen518055 China The State Key Laboratory of Virtual Reality Technology and Systems School of Automation Science and Electrical Engineering Beihang University Beijing100083 China The School of Electrical and Information Engineering Changsha University of Science and Technology Changsha410114 China The State Key Laboratory for Management and Control of Complex Systems Institute of Automation Chinese Academy of Sciences Beijing100190 China

ISBN: (纸本)9781665426473

Change detection (CD) is an important preprocessing process in visual perception. Due to the difficulties of collection and labeling images in water scnens, the design and validation of the change detection algorithm is more difficult than expected. In this paper, we present a novel visual perception framework based on parallel vision for unmanned aerial vehicle (UAV). The visual perception framework consists of artificial scenes, computational experiments and parallel execution. In artificial scenes, we construct a water scene and automatically generated pixel-level image annotation. Next, computational experiments are carried out on different domain dataset. The experiment results show that: 1) mixed images effectively improve the performance of change detection model;2) domain shift problems still greatly affect the algorithm performance. © 2021 IEEE

关键词： Change detection

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Benefit from public unlabeled data: A Frangi filtering-based pretraining network for 3D cerebrovascular segmentation

arXiv

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arXiv 2023年

作者： Shi, Gen Lu, Hao Hui, Hui Tian, Jie School of Engineering Medicine School of Biological Science and Medical Engineering Beihang University Beijing100191 China Ministry of Industry and Information Technology of China Beijing100191 China State Key Laboratory for Management and Control of Complex Systems Institute of Automation Chinese Academic of Science Beijing10086 China CAS Key Laboratory of Molecular Imaging Institute of Automation Chinese Academy of Sciences Beijing100190 China

The precise cerebrovascular segmentation in time-of-flight magnetic resonance angiography (TOF-MRA) data is crucial for clinically computer-aided diagnosis. However, the sparse distribution of cerebrovascular structures in TOF-MRA results in an exceedingly high cost for manual data labeling. The use of unlabeled TOF-MRA data holds the potential to enhance model performance significantly. In this study, we construct the largest preprocessed unlabeled TOF-MRA datasets (1510 subjects) to date. We also provide three additional labeled datasets totaling 113 subjects. Furthermore, we propose a simple yet effective pertraining strategy based on Frangi filtering, known for enhancing vessel-like structures, to fully leverage the unlabeled data for 3D cerebrovascular segmentation. Specifically, we develop a Frangi filtering-based preprocessing workflow to handle the large-scale unlabeled dataset, and a multi-task pretraining strategy is proposed to effectively utilize the preprocessed data. By employing this approach, we maximize the knowledge gained from the unlabeled data. The pretrained model is evaluated on four cerebrovascular segmentation datasets. The results have demonstrated the superior performance of our model, with an improvement of approximately 3% compared to state-of-the-art semi- and self-supervised methods. Furthermore, the ablation studies also demonstrate the generalizability and effectiveness of the pretraining method regarding the backbone structures. The code and data have been open source at: https://***/shigen-StoneRoot/FFPN. © 2023, CC BY.

关键词： Computer aided diagnosis

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Self-Attention based Temporal Intrinsic Reward for Reinforcement Learning

Self-Attention based Temporal Intrinsic Reward for Reinforce...

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2021 China automation Congress, CAC 2021

作者： Jiang, Zhuo Tian, Daiying Yang, Qingkai Peng, Zhihong The School of Automation Beijing Institute of Technology Beijing China State Key Laboratory of Intelligent Control and Decision of Complex System Beijing China Peng Cheng Laboratory Guangdong Shenzhen China

ISBN: (纸本)9781665426473

This paper proposes a self-attention based temporal intrinsic reward model for reinforcement learning (RL), to synthesize the control policy for the agent constrained by the sparse reward in partially observable environments. This approach can solve the problem of temporal credit assignment to some extent and deal with the low efficiency of exploration. We first introduce a sequence-based self-attention mechanism to generate the temporary features, which can effectively capture the temporal property of the task for the agent. During the training process, the temporary features are employed in each sampled episode to elaborate the intrinsic rewards, which is combined with the extrinsic reward to help the agent learn a feasible policy. Then we use the meta-gradient to update this intrinsic reward model in order that the agent can achieve better performance. Experiments are given to demonstrate the superiority of the proposed method. © 2021 IEEE

关键词： Reinforcement learning

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Multi-Objective Optimization of Operation of Power-Traffic systems Considering Dynamic Wireless Charging

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IFAC-PapersOnLine 2023年第2期56卷 6654-6659页

作者： Ze Zhou Zhitao Liu Hongye Su Liyan Zhang Wenhai Wang State Key Laboratory of Industrial Control Technology Institute of Cyber-Systems and Control Zhejiang University Hangzhou 310027 China School of Automation Wuhan University of Technology Wuhan 430070 China Zhejiang University NGICS Platform Hangzhou 310027 China

To reduce the consumption of fossil fuels, improve the environment, and optimize the energy structure, electric vehicles (EVs) have been developed rapidly. At the same time, to alleviate the range anxiety of EV users, the corresponding dynamic wireless charging (DWC) technology has also attracted extensive attention. Driven by EVs and DWC, the interdependency between the power system and transportation system becomes tighter. To improve the operation of the power-traffic system, we propose a multi-objective optimization problem incorporating transportation system congestion, power system generation cost, and total EV user charging cost. Assuming that the energy provided by the DWC can meet the consumption in EV travel, we construct a power demand model for grid buses. Furthermore, we model the microscopic characteristics of vehicle behaviors and propose an adaptive route recommendation algorithm. To solve the multi-objective problem, we adopt a non-dominated sorting genetic algorithm II. Finally, the case studies demonstrate the feasibility of the proposed multi-objective optimization problem and the effectiveness and superiority of the proposed algorithm.

关键词： Dynamic wireless charging electric vehicles multi-objective optimization power-traffic systems route recommendation algorithm

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Simulation and Analysis of Dynamic Stiffness of Electro-hydrostatic Actuators 9

Simulation and Analysis of Dynamic Stiffness of Electro-hydr...

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9th International Conference on Fluid Power and Mechatronics, FPM 2023

作者： Jiang, Chaofan Shang, Yaoxing Yu, Tian Li, Mingyang Wu, Shuai Liu, Zhicheng School of Automation Science and Electrical Engineering Beihang University Beijing China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University Hangzhou China Ningbo Institute of Technology Beihang University Ningbo China Tianmushan Laboratory Xixi Octagon City Yuhang District Hangzhou China Science and Technology on Aircraft Control Laboratory Beihang University Beijing China Research Institute for Frontier Science Beihang University Beijing China

ISBN: (纸本)9798350304947

With the development of multi-electrochemical aircraft, the application of electro-hydrostatic actuators(EHA) in aircraft actuator system is increasing. The dynamic stiffness of the actuator has a non-negligible effect on the fluttering characteristics of the rudder surface. So it is necessary to study the dynamic stiffness of EHA. In this research, a method for calculating the dynamic stiffness of EHA is proposed. The mathematical model of EHA is established. The bulk modulus of hydraulic oil affected by gas content and pressure is added to the model. Build the simulation model in Simulink. The dynamic stiffness of EHA is simulated in frequency domain. Analyze the simulation results. The EHA dynamic stiffness decreases with the increase of hydraulic oil gas content in the whole frequency range. The trough frequency of dynamic stiffness amplitude decreases with the increase of hydraulic oil gas content. The EHA dynamic stiffness decreases with the increase of pump leakage coefficient in low frequency band. Therefore, in order to improve the dynamic stiffness of EHA, the hydraulic oil gas content and the piston pump leakage coefficient should be reduced. © 2023 IEEE.

关键词： Elastic moduli

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Data-Driven Learning and control with Event-Triggered Measurements

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IEEE Transactions on Automatic control 2025年

作者： Feng, Shilun Shi, Dawei Chen, Tongwen Shi, Ling Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex Systems MIIT Key Laboratory of Servo Motion System Drive and Control School of Automation Beijing100081 China University of Alberta Department of Electrical and Computer Engineering EdmontonABT6G 1H9 Canada Hong Kong University of Science and Technology Department of Electronic and Computer Engineering Clear Water Bay Kowloon Hong Kong

Event-triggered control has attracted considerable attention for its effectiveness in resource-restricted applications. To make event-triggered control as an end-to-end solution, a key issue is how to effectively learn unknown system dynamics from event-triggered measurements and consequently, develop a learning-based event-triggered controller. Existing works learn system dynamics based on periodic time-triggered measurements, and it is yet to know how to learn a controller with performance guarantee based on event-triggered measurements. To address this issue, we consider the problem of learning an event-triggered state feedback controller for an unknown linear system based on event-triggered state measurements in this work. In particular, we first analyze the event-triggered measurements within a set-membership framework. We prove that the estimation error belongs to a bounded ellipsoid determined by the historical measurements and the event-triggering condition. Subsequently, we demonstrate that all admissible systems compatible with the collected data samples can be explicitly represented in the form of quadratic matrix inequalities using the state estimates. With the acquired set of admissible systems, a co-design problem for the data-driven controller and event-triggering condition is solved using the linear matrix inequality technique, with guaranteed closed-loop stability and L2-gain performance. Finally, numerical examples and comparisons are provided to illustrate the effectiveness of the proposed event-triggered learning and control approach. © 1963-2012 IEEE.

关键词： Networked control systems

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Dynamic Identification for a Manipulator Model based on Stribeck Friction using the Quasi-Newton Iterative Method

Dynamic Identification for a Manipulator Model based on Stri...

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2023 IEEE International Conference on Robotics and Biomimetics, ROBIO 2023

作者： Xiao, Feng Zhang, Feilong Han, Bing Zhang, Hualiang Shenyang University of Technology School of Information Science and Engineering Shenyang110870 China University of Chinese Academy of Sciences Beijing100049 China Shenyang Institute of Automation Chinese Academy of Sciences Key Laboratory of Networked Control Systems Shenyang110016 China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of Sciences Shenyang110169 China School of Mechanical Engineering Zhejiang University State Key Laboratory of Fluid Power and Mechatronic Systems Hangzhou310027 China

ISBN: (纸本)9798350325706

The performance of dynamic control is intimately tied to modeling accuracy. However, traditional estimation methods and friction models, such as the least squares method and the Coulomb plus viscous model, fail to reflect the actual characteristics accurately. Particularly, the linear nature of the Coulomb plus viscous model overlooks the nonlinear static features of joint friction at slower velocities. To improve the rationality of the model structure, we integrate the Stribeck friction model into the Coulomb plus viscous model. However, introducing such nonlinearities compromises the applicability of the least squares method. As a countermeasure, we propose a new strategy that combines the least square method and the Quasi-Newton iterative method to identify the parameters of the modified nonlinear model. Additionally, the design of the excitation trajectory is critical to achieve high identification accuracy. We utilized the inverse of the smallest singular value of the observation matrix as the objective function. By minimizing it with the interior point method, we generate the excitation trajectory well-suited to stimulate dynamic characteristics. Then we leverage the discrepancies between the measured and estimated torques to assess the precision of the dynamic parameters of the manipulator. Remarkably, our proposed algorithm reduces the mean absolute error of the estimated torque by over 20.40%. Finally, an experiment of the industrial manipulator by hand guiding grab and drag is performed and shows that the proposed approach can provide the manipulator with comprehensive torque compensation. © 2023 IEEE.

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Asynchronous $\mathcal{L}_{1}$-gain Filtering of Nonlinear Positive Semi-Markov Jump systems with Time-varying Delays

Asynchronous $\mathcal{L}_{1}$-gain Filtering of Nonlinear P...

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Chinese control Conference (CCC)

作者： Chao Ma Hang Fu Yidao Ji Wei Wu School of Mechanical Engineering University of Science and Technology Beijing China State Key Lab of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences China

In this paper, the $\mathcal{L}_{1}$ -gain based filtering problem for nonlinear positive semi-Markov jump systems is investigated by proposing a novel asynchronous design approach. More precisely, the mode-dependent... 详细信息

ISBN: (数字)9789887581536

ISBN: (纸本)9781665482561

In this paper, the $\mathcal{L}_control$ -gain based filtering problem for nonlinear positive semi-Markov jump systems is investigated by proposing a novel asynchronous design approach. More precisely, the mode-dependent filters are designed in terms of practical observed modes instead of true system modes, such that less conservatism can be achieved. In addition, the effect of time-varying delays is taken into account for more robustness and applicability. By selecting suitable stochastic Lyapunov-Krasovskii functions and applying the linear programming method, sufficient conditions are established to fulfill the desired $\mathcal{L}_control$ -gain performance. Eventually, the illustrative simulation is performed to verify the effectiveness of our developed control scheme.

关键词： Maximum likelihood detection Sufficient conditions Filtering Hidden Markov models Stochastic processes Nonlinear filters Linear programming

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GAS-LIQUID COUPLING ATTENUATOR ARRAY FOR FLUID PULSATION IN VARIABLE PRESSURE HYDRAULIC systems

GAS-LIQUID COUPLING ATTENUATOR ARRAY FOR FLUID PULSATION IN ...

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2024 CSAA/IET International Conference on Aircraft Utility systems, AUS 2024

作者： Yang, Haodong Xu, Yuanzhi Wang, Renyuan Liao, Jian Zhou, Fuming Yu, Shuai Zhang, Hongbo Jiao, Zongxia School of Automation Science and Electrical Engineering Beihang University Beijing100191 China Key Laboratory of Advanced Airborne Systems Beihang University Beijing100191 China Ningbo Institute of Technology Beihang University Ningbo315800 China Tianmushan Laboratory Hangzhou310023 China Institute of Vibration and Noise Naval University of Engineering Wuhan430033 China State Key Laboratory of Ship Vibration and Noise Wuhan430033 China Shanghai Hunter Hydraulic Control. Technology-Co. Ltd Shanghai201612 China CSSC-No. 704-Research-Institution Shanghai200031 China

The pressure pulsation of variable pressure hydraulic system has the characteristics of wide range and wide frequency band, aiming at the pressure pulsation suppression demand of this system, this paper proposes a wide-pressure and wide-frequency gas-liquid coupling attenuator array structure. This structure utilizes the gas-liquid coupling principle to absorb pulsation, achieving complete coverage of the system's variable pressure range in the time domain and broadening the optimal pulsation absorbing frequency band in the frequency domain through the simultaneous use of multiple attenuators pre-charged with different pressure gases. This paper analyses the principle of gas-liquid coupling for absorbing flow pulsation, establishes a mathematical model of the device, studies the frequency-domain impedance characteristics of the structure using the impedance method, and utilizes the simulation software AMESim to investigate the impact of the array structure on the pulsation attenuation capabilities in the time and frequency domains. The simulation results are analysed to verify the wide-pressure and wide-frequency characteristics of the proposed array structure. © The Institution of Engineering & Technology 2024.

关键词： Frequency domain analysis

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