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Sliding mode control based guidance law with impact angle constraint

Chinese Journal of Aeronautics 2014年第1期27卷 145-152页

作者： Zhao Yao Sheng Yongzhi Liu Xiangdong School of Automation Beijing Institute of Technology Key Laboratory for Intelligent Control & Decision of Complex Systems Beijing Institute of Technology

The terminal guidance problem for an unpowered lifting reentry vehicle against a sta- tionary target is considered. In addition to attacking the target with high accuracy, the vehicle is also expected to achieve a desired impact angle. In this paper, a sliding mode control （SMC）-based guidance law is developed to satisfy the terminal angle constraint. Firstly, a specific sliding mode function is designed, and the terminal requirements can be achieved by enforcing both the sliding mode function and its derivative to zero at the end of the flight. Then, a backstepping approach is used to ensure the finite-time reaching phase of the sliding mode and the analytic expression of the control effort can be obtained. The trajectories generated by this method only depend on the initial and terminal conditions of the terminal phase and the instantaneous states of the vehicle. In order to test the performance of the proposed guidance law in practical application, numerical simulations are carried out by taking all the aerodynamic parameters into consideration. The effec- tiveness of the proposed guidance law is verified by the simulation results in various scenarios.

关键词： Backstepping Impact angle Sliding mode control Terminal guidance Unpowered lifting reentryvehicle

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High-order sliding mode attitude controller design for reentry flight

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Journal of systems Engineering and Electronics 2014年第5期25卷 848-858页

作者： Liang Wang Yongzhi Sheng Xiangdong Liu School of Automation Beijing Institute of Technology Key Laboratory for Intelligent Control & Decision of Complex Systems Beijing Institute of Technology

A novel high-order sliding mode control strategy is proposed for the attitude control problem of reentry vehicles in the presence of parametric uncertainties and external disturbances, which results in the robust and accurate tracking of the aerodynamic angle commands with the finite time convergence. The proposed control strategy is developed on the basis of integral sliding mode philosophy, which combines conventional sliding mode control and a linear quadratic regulator over a finite time interval with a free-final-state and allows the finite-time establishment of a high-order sliding mode. Firstly, a second-order sliding mode attitude controller is designed in the proposed high-order siding mode control framework. Then, to address the control chattering problem, a virtual control is introduced in the control design and hence a third-order sliding mode attitude controller is developed, leading to the chattering reduction as well as the control accuracy improvement. Finally, simulation examples are given to illustrate the effectiveness of the theoretical results.

关键词： reentry vehicle attitude control high-order sliding mode control integral sliding mode.

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Path planning for unmanned aerial vehicles in surveillance tasks under wind fields

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Journal of Central South University 2014年第8期21卷 3079-3091页

作者：张兴陈杰辛斌 School of Automation Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex Systems

The optimal path planning for fixed-wing unmanned aerial vehicles(UAVs) in multi-target surveillance tasks(MTST) in the presence of wind is *** take into account the minimal turning radius of UAVs,the Dubins model is used to approximate the dynamics of *** on the assumption,the path planning problem of UAVs in MTST can be formulated as a Dubins traveling salesman problem(DTSP).By considering its prohibitively high computational cost,the Dubins paths under terminal heading relaxation are introduced,which leads to significant reduction of the optimization scale and difficulty of the whole ***,in view of the impact of wind on UAVs' paths,the notion of virtual target is *** application of the idea successfully converts the Dubins path planning problem from an initial configuration to a target in wind into a problem of finding the minimal root of a transcendental ***,the Dubins tour is derived by using differential evolution(DE) algorithm which employs random-key encoding technique to optimize the visiting sequence of ***,the effectiveness and efficiency of the proposed algorithm are demonstrated through computational *** results exhibit that the proposed algorithm can produce high quality solutions to the problem.

关键词： unmanned aerial vehicle path planning in wind field Dubins traveling salesman problem terminal heading relaxation differential evolution

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Research on pump-HA motor speed control system based on switched PID control

Research on pump-HA motor speed control system based on swit...

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Chinese Automation Congress (CAC)

作者： Hao Jiang Shoukun Wang Junzheng Wang Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing Institute of Technology Beijing P. R. China

ISBN: (纸本)9781467371902

Aiming to improve the control precision of pump-HA(high pressure automatic variables) motor speed control systems, the characteristic of HA motor displacement control mechanism is analyzed, and the mathematical model of pump-HA motor system is established. Taking the nonlinear character of the system, the system is approximated to a few of first order plus time delay processes, according to the working conditions. Parameters of the system models under different working conditions are identified by step response identification, PID parameters are tuned by a parameter tuning algorithm. A UKF state estimator is designed to estimate the load torque on the basis of the state space model established, then PID parameters are switched according to the desired speed and load torque. The research results indicate that switched PID control can ensure the system always has a good dynamic performance under different conditions and improve the control precision, making the system deal with various complex working conditions.

关键词： Yttrium Oscillators

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Finite-time sliding mode attitude control for a reentry vehicle with blended aerodynamic surfaces and a reaction control system

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Chinese Journal of Aeronautics 2014年第4期27卷 964-976页

作者： Geng Jie Sheng Yongzhi Liu Xiangdong Key Laboratory for Intelligent Control&Decision of Complex Systems Beijing Institute of Technology School of Automation Beijing Institute of Technology

This paper proposes a finite-time robust flight controller, targeting for a reentry vehicle with blended aerodynamic surfaces and a reaction control system（RCS）. Firstly, a novel finite-time attitude controller is pointed out with the introduction of a nonsingular finite-time sliding mode manifold. The attitude tracking errors are mathematically proved to converge to zero within finite time which can be estimated. In order to improve the performance, a second-order finite-time sliding mode controller is further developed to effectively alleviate chattering without any deterioration of robustness and accuracy. Moreover, an optimization control allocation algorithm, using linear programming and a pulse-width pulse-frequency（PWPF） modulator, is designed to allocate torque commands for all the aerodynamic surface deflections and on–off switching-states of RCS *** are provided for the reentry vehicle considering uncertain parameters and external disturbances for practical purposes, and the results demonstrate the effectiveness and robustness of the attitude control system.

关键词： Chattering alleviation control allocation Finite-time convergence Flight control systems Second-order sliding mode Singularity elimination Sliding mode control

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Leader-Following Consensus of Discrete-Time Linear Multi-Agent systems with Communication Noises

Leader-Following Consensus of Discrete-Time Linear Multi-Age...

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第三十四届中国控制会议

作者： Yunpeng Wang Long Cheng Hongming Wang Zeng-Guang Hou Min Tan Hongnian Yu State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing Institute of Technology China North Vehicle Research Institute Faculty of Science and Technology Bournemouth University

ISBN: (纸本)9781467374439

This paper studies the leader-following consensus problem of discrete-time generic linear multi-agent systems. Agents share their states with their neighbors via a noisy communication network. An algorithm is proposed for the leader-following consensus problem where the time-varying gain is employed to attenuate noises. Different from most previous results where all agents have to use the same time-varying gain, each agent can have its own time-varying gain. Sufficient conditions for solving the mean square leader-following consensus problem are obtained: 1) the communication topology graph has a spanning tree;2) the summation of every time-varying gain from zero to infinite is infinite;3) all time-varying gains are infinitesimal of the same order as time goes to infinity;and 4) all roots of a so-called "parameter polynomial" are inside the unit circle. Finally, a simulation example is given to verify the theoretical results.

关键词： Multi-Agent system,Leader-following consensus,Mean square,Communication noise.

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Study of control Parameters Tuning Method for Hydro-viscous Driver System

Study of Control Parameters Tuning Method for Hydro-viscous ...

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2015 International Conference on Fluid Power and Mechatronics

作者： Deyang Zhang Shoukun Wang Junzheng Wang Ligang Ma Key Laboratory of Intelligent Control and Decision of Complex Systems School of Automation Beijing Institute of Technology Chinese North Vehicle Research Institute

Hydro-viscous speed clutch(HVC) is a central control element of the driver system. Because of nonlinearities and hysteresis of the clutch, the setting of control parameters has a significant impact on the performance of the speed control system. This paper studies the HVC of a vehicle temperature control system, and analyzes the parameters tuning method of a PID controller for the closed-loop control system. By employing a two-storey optimized control framework, the resulting model from identification can be used to complete the control parameters auto-tuning. Simulation and experimental results have showed that this auto-tuning method can obtain a group of parameters in terms of a desired performance index, which guarantees the balance of dynamic characteristics, stability and anti-jamming in closed-loop system.

关键词： hydro-viscous driver system model identification parameters tuning method

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A Method of SMS Spam Filtering Based on AdaBoost Algorithm

A Method of SMS Spam Filtering Based on AdaBoost Algorithm

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World Congress on intelligent control and Automation

作者： Xipeng Zhang Gang Xiong Yuexiang Hu Fenghua Zhu Xisong Dong Timo R. Nyberg State Key Laboratory of Management and Control for Complex Systems Institute of Automation of Chinese Academy of Science Beijing CO 100190 China Cloud Computing Center Chinese Academy of Sciences Dongguan CO 523000 China Hainan Zhongke Flower Ocean Cloud Commerce Technology Co. Ltd Haikou CO570311 Hainan China Beijing Engineering Research Center of Intelligent Systems and Technology Institute of Automation Chinese Academy of Sciences Beijing CO 100190 China Qingdao Academy of Intelligent Industries Qingdao CO 266061 China Department of Industrial Engineering and Management Aalto University Aalto CO FI-00076 Finland

ISBN: (纸本)9781467384155

Short message is one of the most common communication media for mobile subscribers, so major mobile operators are devoted to improve their Short Message Service (SMS). However, the annoying and undesired messages, also named message spam or simply spam, not only worsen the users' experience, but also cause their complaints on SMS. In this paper, we present a novel Chinese SMS spam filtering framework based on AdaBoost algorithm to provide accurate and effective short messages classification. Three content-based weak filters are introduced to boost the performance of final classification decision. Results from Receiver Operating Characteristics (ROC) analysis prove the proposed method has such advantages as higher efficiency and fewer parameters over those established SMS spam filtering methods. The application of the proposed method is expected to block the most spam for mobile subscribers and improve the service quality of SMS. With simple data processing and few training parameters, the proposed method can be applied into the practice of short text classification.

关键词： Filtering Mobile communication Training Unsolicited electronic mail Classification algorithms Text categorization Bayes methods

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Visualisation of the Early-Stage Vibration of the Automatic-Gauge-control Hydraulic Cylinder Based on the Acoustic Emission Hits-Density Imaging

Visualisation of the Early-Stage Vibration of the Automatic-...

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2015年中国智能自动化学术会议

作者： Hongzhi Chen Yongli Zhao Jie Huang Chang Cheng State Key Laboratory of Hybrid Process Industry Automation System and Equipment Technology Automation Research and Design Institute of Metallurgical Industry Key Laboratory of Intelligent Control and Decision of Complex Systems School of Automation Beijing Institute of Technology Fujian Institute of Education

By taking into account the hits-density imaging technique that has been introduced by authors' previous publications, the acoustic emission bursts emitted from the automatic-gauge-control hydraulic cylinder under normal loading and early-stage vibration were investigated. First, six acoustic emission descriptors that showed significance regarding the cumulative probability distribution were visualised, followed by the reconstruction of the hits-density images using these features;Through the visual examination of the hits-density images regarding the cylinders' normal loading and early-stage vibration, apparent visual differences between normal and early-stage vibration under the same loading can be observed;By projecting the hits-density images onto the principal component space, a trajectory which represents the condition developments was observed, which shows a visual-based resolution for dealing with vast transient bursts data reduction,reconstruction and visualisation.

关键词： Visualisation Hits-density imaging Early-stage vibration Acoustic emission

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On Finite-Horizon Optimal control of First-Order Plus Time Delay systems

On Finite-Horizon Optimal Control of First-Order Plus Time D...

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第27届中国控制与决策会议

作者： Dawei Shi Tongwen Chen State Key Laboratory of Intelligent Control and Decision of Complex Systems School of AutomationBeijing Institute of Technology Department of Electrical and Computer Engineering University of Alberta

In this work,a finite-horizon optimal control problem for first-order plus time delay(FOPTD) processes is *** show that if the control horizon is greater than three and the prediction horizon is great than the control horizon plus the time delay in discrete time,the optimal controller is not affected by either of the two ***,under these conditions,the controller parameters are explicitly calculated,the closed-loop system is shown to be stable,and the controller is *** problem considered is related to the results on linear quadratic regulation of linear systems with time delays;however,the detailed parameterization of the state-space model introduced by the FOPTD process provides an additional opportunity to investigate the exact controller structure and properties(e.g.,the locations of the closed-loop poles),which are also the major difficulties encountered and overcome in this *** problem is motivated from phenomena experienced in designing industrial model predictive control(MPC) tuning algorithms,and extensive numerical examples indicate that the proposed results speed up the MPC autotuning algorithms by 70%.

关键词： Optimal control First-order plus time delay process Performance visualization MPC tuning

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