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Interval analysis for neural networks with application to fault detection

science China(Information sciences) 2024年第11期67卷 222-237页

作者： Zhenhua WANG Youdao MA Song ZHU Thach Ngoc DINH Yi SHEN Department of Control Science and Engineering Harbin Institute of Technology National Key Laboratory of Complex System Control and Intelligent Agent Cooperation School of Mathematics China University of Mining and Technology The CEDRIC-Lab Conservatoire National des Arts et Métiers (CNAM)

This paper investigates an interval analysis method for neural networks and applies it to fault detection for systems with unknown but bounded measurement noise. First, a novel interval analysis method is presented, which can compute the bounds of the output of a feedforward neural network subject to a bounded input. By applying the proposed interval analysis method to a network trained with fault-free system data, adaptive thresholds for fault detection are computed. Finally, one can acquire fault detection results via a fault detection strategy. The proposed method can achieve tight bounds of the network output and employ simple operations, which leads to accurate fault detection results and a low computational burden.A numerical simulation and an experiment on an AC servo motor are given to illustrate the effectiveness and superiority of the proposed method.

关键词： interval analysis feedforward neural network fault detection adaptive thresholds

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Simulation of Nanosecond Microwave Pulse Amplification Based on a Gyrotron Traveling Wave Tube

Simulation of Nanosecond Microwave Pulse Amplification Based...

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2024 Photonics and Electromagnetics Research Symposium, PIERS 2024

作者： Pan, Ruoyang Zhang, Zhiyuan Liu, Guo Wang, Weijie Yao, Yelei Jiang, Wei Wu, Zewei Pu, Youlei Wang, Jianxun Luo, Yong University of Electronic Science and Technology of China School of Electronic Science and Engineering Chengdu China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing China

ISBN: (纸本)9798350375909

The paper presents the simulation results for nanosecond pulse amplification utilizing a TE11 mode Ku-band gyrotron traveling wave tube (gyro-TWT). This study evaluates the output performance across various input pulse widths within the 15-17 GHz frequency range. Simulations show that the minimum output pulse width is 0.8 ns, with an output power of 183.9 kW. Moreover, when input pulse widths exceed 2 ns, it is observed that the tube can attain a saturated output power of 293.1 kW, with negligible disparity between input and output pulse widths. The gyro-TWT can serve as a nanosecond pulse source, with potential applications in fields such as military radar, biomedicine, and microwave chemistry. © 2024 IEEE.

关键词： Military radar

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Broadband and High-Power Sub-terahertz Gyro-TWTs and Ultrashort Electromagnetic Pulse Generation 5th

Broadband and High-Power Sub-terahertz Gyro-TWTs and Ultrash...

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5th China and International Young Scientist Terahertz Conference, YTHZ 2024

作者： Liu, Guo Jiang, Wei Yao, Yelei Wang, Weijie Cao, Yingjian Wang, Yu Wu, Zewei Pu, Youlei Wang, Jianxun Luo, Yong University of Electronic Science and Technology of China Chengdu611731 China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing100089 China

ISBN: (纸本)9789819739127

In this paper, a short demonstration about the recent progress of our high-power broadband gyrotron travelling wave tube (gyro-TWT) amplifiers in the sub-terahertz band (W and G-band) are respectively reported. Hot test of the W- and G-band gyro-TWTs had respectively achieved a pulsed/averaged output power of over 120 kW/20 kW and 35 kW/2.1 kW within a 10 GHz bandwidth. Based on the fabricated sub-terahertz gyro-TWTs, a scheme to generate high power, ultrashort electromagnetic pulses based on the chirped signal compressor is also presented, which had been verified in the micro- and millimeter wave band. The presented sub-terahertz high-power sources and ultrashort pulses have potential applications in the high-resolution imaging radar, deep space communication, bio-medicine, material modification and catalysis, etc. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Gyroscopes

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Fixed-Time Sliding Mode control With Varying Exponent Coefficient for Modular Reconfigurable Flight Arrays

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 514-528页

作者： Jianquan Yang Chunxi Yang Xiufeng Zhang Jing Na Faculty of Mechanical and Electrical Engineering Kunming University of Science and TechnologyKunming 650500 Yunnan International Joint Laboratory of Intelligent Control and Aoolication of Advanced Equipment Kunming 650500China IEEE

The modular system can change its physical structure by self-assembly and self-disassembly between modules to dynamically adapt to task and environmental requirements. Recognizing the adaptive capability of modular systems, we introduce a modular reconfigurable flight array(MRFA) to pursue a multifunction aircraft fitting for diverse tasks and requirements,and investigate the attitude control and the control allocation problem by using the modular reconfigurable flight array as a platform. First, considering the variable and irregular topological configuration of the modular array, a center-of-mass-independent flight array dynamics model is proposed to allow control allocation under over-actuated situations. Secondly, in order to meet the stable, fast and accurate attitude tracking performance of the MRFA, a fixed-time convergent sliding mode controller with state-dependent variable exponent coefficients is proposed to ensure fast convergence rate both away from and near the system equilibrium point without encountering the singularity. It is shown that the controller also has fixed-time convergent characteristics even in the presence of external disturbances. Finally,simulation results are provided to demonstrate the effectiveness of the proposed modeling and control strategies.

关键词： control allocation dynamic model fixed-time stabilization modular reconfigurable flight array(MRFA) sliding mode

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Q-Learning-Based Target Selection for Bearings-Only Autonomous Navigation

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Journal of Systems science & Complexity 2021年第4期34卷 1401-1425页

作者： XIONG Kai WEI Chunling Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control EngineeringBeijing 100094China

This paper presents a Q-learning-based target selection algorithm for spacecraft autonomous navigation using bearing observations of known visible *** the considered navigation system,the position and velocity of the spacecraft are estimated using an extended Kalman filter(EKF)with the measurements of inter-satellite line-of-sight(LOS)vectors obtained via an onboard star *** paper focuses on the selection of the appropriate target at each observation period for the star camera adaptively,such that the performance of the EKF is *** derive an effective algorithm,a Q-function is designed to select a proper observation region,while a U-function is introduced to rank the targets in the selected *** the Q-function and the U-function are constructed based on the sequence of innovations obtained from the *** efficiency of the Q-learning-based target selection algorithm is illustrated via numerical simulations,which show that the presented algorithm outperforms the traditional target selection strategy based on a Cramer-Rao bound(CRB)in the case that the prior knowledge about the target location is inaccurate.

关键词： Bearings-only autonomous navigation convergence analysis extended Kalman filtering Q-Learning target selection

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Exploring reservoir computing:Implementation via double stochastic nanowire networks

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Chinese Physics B 2024年第3期33卷 572-582页

作者：唐健峰夏磊李广隶付军段书凯王丽丹 College of Artificial Intelligence Southwest UniversityChongqing 400715China Brain-inspired Computing & Intelligent Control of Chongqing Key Laboratory Chongqing 400715China National & Local Joint Engineering Laboratory of Intelligent Transmission and Control Technology Chongqing 400715China Chongqing Brain Science Collaborative Innovation Center Chongqing 400715China Key Laboratory of Luminescence Analysis and Molecular Sensing Ministry of EducationSouthwest UniversityChongqing 400715China State Key Laboratory of Intelligent Vehicle Safety Technology Chongqing 400715China

Neuromorphic computing,inspired by the human brain,uses memristor devices for complex *** studies show that self-organizing random nanowires can implement neuromorphic information processing,enabling data *** paper presents a model based on these nanowire networks,with an improved conductance variation *** suggest using these networks for temporal information processing via a reservoir computing scheme and propose an efficient data encoding method using voltage *** nanowire network layer generates dynamic behaviors for pulse voltages,allowing time series prediction *** experiment uses a double stochastic nanowire network architecture for processing multiple input signals,outperforming traditional reservoir computing in terms of fewer nodes,enriched dynamics and improved prediction *** results confirm the high accuracy of this architecture on multiple real-time series datasets,making neuromorphic nanowire networks promising for physical implementation of reservoir computing.

关键词： double-layer stochastic(DS)nanowire network architecture neuromorphic computation nanowire network reservoir computing time series prediction

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Accuracy Evaluation of Marginalized Unscented Kalman Filter

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space(science & technology) 2023年第1期3卷 597-605页

作者： Han Yan Hanyu Liu Xiucong Sun Ming Xu National Key Laboratory of Space Intelligent Control Beijing Institute of Control EngineeringBeijingChina Beijing Sun Wise Space Technology Ltd BeijingChina Beihang University BeijingChina

Compared with a conventional unscented Kalman filter(UKF),the recently proposed marginalized unscented Kalman filter(MUKF)uses a partially sampling strategy to achieve similar filter accuracy with fewer sigma points,demonstrating its powerful ability to deal with state estimation with mixed linearity and ***,the hypothesis that the accuracy of MUKF is equivalent to that of UKF is not true for all *** this paper,it is proved that when the state equation is expressed as a differential equation,the accuracy of MUKF is equivalent to that of UKF only when the propagations of the states to be sampled and the states not to be sampled in MUKF are independent of each *** above condition corresponds to a common problem in engineering,which is a system with measurement *** theoretical proof and numerical simulation,it is verified in this paper that for the systems with measurement biases,the differences of the computed means and covariances in filtering recursions between MUKF and UKF are restricted to the same order infinitesimal as the square of the scaling *** sum up,this paper evaluates the accuracy of MUKF,providing references for engineers to choose MUKF or UKF in different systems.

关键词： filtering equation scaling

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Analysis of Transceiver RF Impairments on Artificial Noise Suppression in Frequency-Hopping Systems

IEEE Transactions on Sustainable Computing

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IEEE Transactions on Sustainable Computing 2024年第3期10卷 475-490页

作者： Song, Changqing Zhao, Hongzhi Yu, Yong Li, Zhuo Shao, Shihai University of Electronic Science and Technology of China National Key Laboratory of Wireless Communications Chengdu611731 China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing100089 China Yangzhou Marine Electronic Instrument Institute Yangzhou225101 China

The artificial noise shielded frequency-hopping (ANFH) architecture can secure wireless communications against interference and eavesdropping. However, the AN suppression performance is highly sensitive to the radio frequency (RF) impairments, and the transceiver in-phase and quadrature (IQ) imbalances and phase noise in FH systems are more severe for the wide FH bandwidth. In this study, the AN-FH transceivers under RF impairments are mathematically modeled. Subsequently, distortions for transceiver phase noise are represented by the common phase error, distortions for transceiver IQ imbalances are represented by the mirror image component, and closed-form expressions for their respective power are derived and compared with the thermal noise power. Finally, the AN suppression capability is evaluated via the AN suppression ratio (ANSR), defined as the ratio of the AN-plus-noise power before and after suppression. It is found that when only phase noise exists, shortening the channel compensation cycle can enhance ANSR and reduce ANSR degradation;when the distortions' power is smaller than the thermal noise power, it is also recommended to enhance the transmitting power and the power ratio of AN to information signals. When only IQ imbalances exist, increasing the power ratio of AN to information signals is suggested;when the distortions' power is smaller than the thermal noise power, enhancing the transmitting power is also suggested © 2016 IEEE.

关键词： Phase noise

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Surface-PMSM Sensorless control Strategy Based on Reduced-Order Linear Kalman Filter Cooperating With Prediction Error Rolling Compensation

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IEEE Transactions on Power Electronics 2025年第8期40卷 10804-10815页

作者： Xu, Sang Shen, Anwen Tang, Qipeng Wang, Miaomiao Luo, Pan Luo, Xin Xu, Jinbang National Key Laboratory of Science and Technology on Multispectral Information Processing Key Laboratory of Image Processing and Intelligent Control School of Artificial Intelligence and Automation Wuhan430074 China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China Chengdu610213 China

Kalman filter (KF) is increasingly attracted for sensorless control of surface permanent magnet synchronous motors due to its strong robustness against measurement and system noise. However, the conventional method suffers from poor position and speed estimation accuracy under dynamic conditions and high computational cost. In order to solve these problems, an enhanced sensorless control strategy based on reduced-order linear Kalman filter (RLKF) cooperating with prediction error rolling compensation is introduced in this article. Differing from conventional methods, a reduced-order linear state equation encompassing rotor position, speed, and torque disturbance is constructed. Then, by obtaining the prediction error of system output using the motor current equation in the predictive reference frame, the optimal estimation of rotor position and speed in the KF algorithm is achieved based on the reduced-order model. This not only simplifies the calculation process but also enhances the position and speed estimation accuracy under dynamic conditions. Meanwhile, a prediction error rolling compensation algorithm is developed to minimize the estimation deviations caused by motor parameter variations. In addition, the system's dynamic performance is further improved with an adopted speed controller based on torque disturbance feedforward and acceleration feedback. Finally, experimental results verify the effectiveness and feasibility of the proposed strategy. © 1986-2012 IEEE.

关键词： Permanent magnets

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Two performance indicators of reaction wheel underactuated configuration 1

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19th Chinese intelligent Systems Conference, CISC 2023

作者： Xie, Jun Feng, Jia-Jia Zhang, Yu-Jie Chen, Qiang Beijing Institute of Control Engineering Beijing100190 China Science and Technology on Space Intelligent Control Laboratory Beijing100190 China

ISBN: (数字)9789819968824

ISBN: (纸本)9789819968817

It is of great engineering significance to study the underactuated configuration of reaction wheels. Aiming at the problem of how to effectively improve the control performance of the control system, this paper proposes two performance optimization indicators in the reaction wheel underactuated configuration from the control mechanism of the underactuated control, which provides a reference for the optimization design of the reaction wheel underactuated configuration. The two performance indicators are the area of the actuated Euler axis and the error angle of the underactuated axis. The simulation analysis of the performance indicators is carried out for an engineering example. The results show that the optimization of the two performance indicators proposed in this paper can effectively improve the control performance of the system under underactuated control. It is proved that the two performance optimization indicators proposed in this paper are feasible and effective, and have certain engineering application value. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023

关键词： Benchmarking

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