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Nonlinear control for a Model-scaled Helicopter with Constraints on Rotor Thrust and Fuselage Attitude

自动化学报 2014年第11期40卷 2654-2664页

作者： ZHU Bing The Seventh Research Division Beihang University Beijing 100191 China Department of Electrical Electronic and Computer Engineering University of Pretoria Pretoria 0083 South Africa Science and Technology on Aircraft Control Laboratory Beihang University Beijing 100191 China

A nonlinear control is proposed for trajectory tracking of a 6-DOF model-scaled helicopter with constraints on main rotor thrust and fuselage attitude. In the procedure of control design, the mathematical model of helicopter is simplified into three subsystems: altitude subsystem, longitudinal-lateral subsystem and attitude subsystem. The proposed control is developed by combining the sub-controls for the corresponding subsystems. The sub-controls for altitude subsystem and longitudinal-lateral subsystem are designed with hyperbolic tangent functions to satisfy the constraints; the sub-control for attitude subsystem is based on backstepping technique such that fuselage attitude tracks the virtual control for longitudinal-lateral subsystem. It is proved theoretically that tracking errors are ultimately bounded, and control constraints are satisfied. Performances of the proposed controller are demonstrated by simulation results.

关键词：直升机旋翼控制模型非线性控制机身姿态推力缩放双曲正切函数

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Maximum work extraction and implementation costs for nonequilibrium Maxwell's demons

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Physical Review E 2014年第4期90卷 042119-042119页

作者： Henrik Sandberg Jean-Charles Delvenne Nigel J. Newton Sanjoy K. Mitter Department of Automatic Control KTH Royal Institute of Technology Stockholm Sweden ICTEAM and CORE Université catholique de Louvain Louvain-la-Neuve Belgium School of Computer Science and Electronic Engineering University of Essex Colchester United Kingdom Laboratory for Information and Decision Systems MIT Cambridge Massachusetts USA

We determine the maximum amount of work extractable in finite time by a demon performing continuous measurements on a quadratic Hamiltonian system subjected to thermal fluctuations, in terms of the information extracted from the system. The maximum work demon is found to apply a high-gain continuous feedback involving a Kalman-Bucy estimate of the system state and operates in nonequilibrium. A simple and concrete electrical implementation of the feedback protocol is proposed, which allows for analytic expressions of the flows of energy, entropy, and information inside the demon. This let us show that any implementation of the demon must necessarily include an external power source, which we prove both from classical thermodynamics arguments and from a version of Landauer's memory erasure argument extended to nonequilibrium linear systems.

关键词： MAXWELL'S demon NONEQUILIBRIUM thermodynamics FLUCTUATIONS (Physics) FEEDBACK control systems ENTROPY

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Design of separating screen for tenebrio molitor L

Design of separating screen for tenebrio molitor L

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International Conference on Vehicle and Mechanical engineering and Information Technology, VMEIT 2014

作者： Wang, Li Ping Guo, Yi Fu, Gang Dong, Jiang Hui College of Mechanical and Electronic Engineering Shanghai Jianqiao University Shanghai 201319 China School of Computer Science Engineering and Mathematics Flinders University SA 5042 Australia Beijing Vocational College of Agriculture Beijing 102442 China China Satellite Maritime Tracking and Control Department Jiangyin 214431 China

ISBN: (纸本)9783038350606

In order to meet requirement of separation screen for tenebrio molitor L, one separation screen was designed, this product has a good separation, simple structure, low cost, high efficiency, easy operation. Based on the analysis of design requirement of separating screen for tenebrio molitor L, overall structure, working principle and the main structural parameters were determined. The kinematic mathematical model of shaking mechanism was established by using the vector method. The kinematics analysis of shaking mechanism was conducted by using Matlab, the displacement, velocity and acceleration curves of sieve box were obtained. The performance test showed that the prototype machine can screen different instar tenebrio molitor L and frass, this machine has good screening effect. In addition, machine design and performance are able to meet the design requirements. © (2014) Trans Tech Publications, Switzerland.

关键词： Machine design

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Design of the splitting and taking pest machine

Design of the splitting and taking pest machine

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International Conference on Vehicle and Mechanical engineering and Information Technology, VMEIT 2014

ISBN: (纸本)9783038350606

In order to meet the requirement of splitting wood to take out the pests in the plant protection research work, the splitting and taking pest machine is designed, which working mode is based on spiral transmission. According to the wear condition, the main structure parameters of the spiral transmission device for splitting were determined. Furthermore, the strength of the dangerous section of screw rod, the strength of nuts' teeth, the self-lock of spiral pair and the stability of screw rod were checked. The virtual prototype of splitting and taking pest machine is made by using SolidWorks software, the motion simulation results show that no interference among the various parts. The test results of the prototype indicate that the machine can meet the job requirement to split wood and take out the pests. In addition, the machine has many features, such as simple structure, working smoothly and low vibration. © (2014) Trans Tech Publications, Switzerland.

关键词： Screws

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Evaluation of the spherical concave mirror and convex lens in compensating turbulence effect on FSO systems

Evaluation of the spherical concave mirror and convex lens i...

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International Symposium on Communication Systems, Networks and Digital Signal Processing, CNSDSP

作者： M. Hulea Z. Ghassemlooy S. Rajbhandari X. Tang Faculty of Automatic Control and Computer Engineering Gheorghe Asachi Technical University of Iasi Romania Optical Communications Research Group Northumbria University Newcastle United Kingdom Department of Engineering Science University of Oxford United Kingdom Tsinghua University Beijing China

This paper focuses on evaluating the performance of two aperture averaging methods used for compensating the effects of the air turbulence in free space optical (FSO) communications. These methods are based on using a concentration lens and spherical concave mirrors (SCM). The preliminary experimental results show that the quality of the received signal in terms of the Q-factor and the scintillation index is moderately improved when employing a lens in comparison to SCM for all turbulence regimes. However, these results were obtained with different collection areas and focal points. Therefore, a more rigorous approach using lens and SCM with the same aperture diameters and focal lengths needs to be adopted to ensure conclusive results.

关键词： Laser beams Lenses Optical beams Apertures Optical fiber communication Mirrors Receivers

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State Feedback Tracking control for Indirect Field-oriented Induction Motor Using Fuzzy Approach

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International Journal of Automation and computing 2013年第2期10卷 99-110页

作者： M. Allouche M. Chaabane M. Souissi D. Mehdi F. Tadeo Laboratory of Sciences and Techniques of Automatic Control and Computer Engineering (Lab-STA) National School of Engineering of SfaxUniversity of Sfax Laboratory of Computer and Automatic for System (LIAS) Higher School of Engineering of Poitiers (ESIP) University of Poitiers Department of Systems Engineering University of Valladolid

This paper deals with the synthesis of fuzzy controller applied to the induction motor with a guaranteed model reference tracking performance. First, the Takagi-Sugeno （T-S） fuzzy model is used to approximate the nonlinear system in the synchronous d-q frame rotating with field-oriented control strategy. Then, a fuzzy state feedback controller is designed to reduce the tracking error by minimizing the disturbance level. The proposed controller is based on a T-S reference model in which the desired trajectory has been specified. The inaccessible rotor flux is estimated by a T-S fuzzy observer. The developed approach for the controller design is based on the synthesis of an augmented fuzzy model which regroups the model of induction machine, fuzzy observer, and reference model. The gains of the observer and controller are obtained by solving a set of linear matrix inequalities （LMIs）. Finally, simulation and experimental results are given to show the performance of the observer-based tracking controller.

关键词： Fuzzy tracking control H∞ performance feedback controller linear matrix inequality （LMI） fuzzy observer

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Sensorless control of switched reluctance motors based on high frequency signal injection

Sensorless control of switched reluctance motors based on hi...

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International Conference on Electrical Machines and Systems (ICEMS)

作者： Rongguang Hu Zhiquan Deng Jun Cai Cheng Wang College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing China School of Information and Control Nanjing University of Information Science and Technology Nanjing China Department of Automatic Control and Systems Engineering The University of Sheffield Sheffield UK

ISBN: (纸本)9781479951635

Sensorless control at low speed is a challenge for Switched Reluctance Motor (SRM). In this paper, a new high frequency signals injection based method is proposed. Since the stator inductance varies with the rotor position θ for its saliency, the responding current contains the position information. With a band pass filter, the high frequency component of current can be acquired then the rotor position can be calculated through series of coordinate transformations and filters. An important feature is that the method doesn't need to know the parameters of the motor and is easy for implementation. Besides, it doesn't require external hardware and hence the reliability is guaranteed while not adding to the system cost. Simulations and experiments are carried out and both steady and dynamic performances of sensorless control using this method are verified.

关键词： Reluctance motors Rotors Estimation Vectors Band-pass filters Sensorless control Inductance

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Materials science/Clinical Medi Cine: Epidermal devices for noninvasive, precise, and continuous mapping of macrovascular and microvascular blood flow

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science Advances 2015年第9期1卷

作者： Webb, R. Chad Ma, Yinji Krishnan, Siddharth Li, Yuhang Yoon, Stephen Guo, Xiaogang Feng, Xue Shi, Yan Seidel, Miles Cho, Nam Heon Kurniawan, Jonas Ahad, James Sheth, Niral Kim, Joseph TaylorVI, James G. Darlington, Tom Chang, Ken Huang, Weizhong Ayers, Joshua Gruebele, Alexander Pielak, Rafal M. Slepian, Marvin J. Huang, Yonggang Gorbach, Alexander M. Rogers, John A. Department of Materials Science and Engineering Frederick Seitz Materials Research Laboratory University of Illinois at Urbana-Champaign UrbanaIL61801 United States Departments of Civil and Environmental Engineering Mechanical Engineering Center for Engineering and Health Skin Disease Research Center Northwestern University EvanstonIL60208 United States Department of Engineering Mechanics Center for Mechanics and Materials Tsinghua University Beijing100084 China Institute of Solid Mechanics Beihang University Beijing100191 China National Institute of Biomedical Imaging and Bioengineering National Institutes of Health BethesdaMD20892 United States College of Aerospace and Civil Engineering Harbin Engineering University Harbin150001 China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics Nanjing210016 China Genomic Medicine Section Hematology Branch National Heart Lung and Blood Institute National Institutes of Health BethesdaMD20892 United States Department of Electrical and Computer Engineering Frederick Seitz Materials Research Laboratory University of Illinois at Urbana-Champaign UrbanaIL61801 United States L'Oreál California Research Center 953 Indiana Street San FranciscoCA94107 United States Department of Medicine Sarver Heart Center Department of Biomedical Engineering University of Arizona TucsonAZ85724 United States

Continuous monitoring of variations in blood flow is vital in assessing the status of microvascular and macrovascular beds for a wide range of clinical and research scenarios. Although a variety of techniques exist, most require complete immobilization of the subject, thereby limiting their utility to hospital or clinical settings. Those that can be rendered in wearable formats suffer from limited accuracy, motion artifacts, and other shortcomings that follow from an inability to achieve intimate, noninvasive mechanical linkage of sensors with the surface of the skin. We introduce an ultrathin, soft, skin-conforming sensor technology that offers advanced capabilities in continuous and precise blood flow mapping. Systematic work establishes a set of experimental procedures and theoretical models for quantitative measurements and guidelines in design and operation. Experimental studies on human subjects, including validation with measurements performed using state-of-the-art clinical techniques, demonstrate sensitive and accurate assessment of both macrovascular and microvascular flow under a range of physiological conditions. Refined operational modes eliminate long-term drifts and reduce power consumption, thereby providing steps toward the use of this technology for continuous monitoring during daily activities. © 2015 The Authors, some rights reserved.

关键词： Blood

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Wi-Fi positioning based on deep learning

Wi-Fi positioning based on deep learning

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International Conference on Information and Automation (ICIA)

作者： Wei Zhang Kan Liu Weidong Zhang Youmei Zhang Jason Gu School of Control Science and Engineering Shandong University Jinan China Department of Electrical and Computer Engineering Dalhousie University Halifax NS Canada

ISBN: (纸本)9781479940998

In this paper, we propose a Wi-Fi positioning method based on Deep Learning (DL). To deal with the variant and unpredictable wireless signals, the positioning is casted in a four-layer Deep Neural Network (DNN) structure that is capable of learning reliable features from a large set of noisy samples and avoids the need for hand-engineering. Also, to maintain the temporal coherence, a Hidden Markov Model (HMM) based fine localizer is introduced to smooth the positioning result obtained from the immediate estimation of DNN-based coarse localizer. The data required for the experiments is collected from the real world in different periods to meet the actual environment. Experimental results indicate that the proposed system leads to substantial improvement on localization accuracy in case of the turbulent wireless signals.

关键词： Feature extraction Hidden Markov models IEEE 802.11 Standards Accuracy Databases Vectors Training

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A new coupled-map car-following model based on a transportation supernetwork framework

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Chinese Physics B 2013年第6期22卷 141-149页

作者：姚静黄婧祎陈关荣许维胜 Department of Control Science and Engineering Tongji University Department of Electronic and Computer Engineering The Hong Kong University of Science and Technology Department of Electronic Engineering City University of Hong Kong

A new car-following model is proposed by considering information from a number of preceding vehicles with intervehicle communication. A supernetwork architecture is first described, which has two layers： a traffic network and a communication network. The two networks interact with and depend on each other. The error dynamic system around the steady state of the model is theoretically analyzed and some nonjam criteria are derived. A simple control signal is added to the model to analyze the criteria of suppressing traffic jams. The corresponding numerical simulations confirm the correctness of the theoretical analysis. Compared with previous studies concerning coupled map models, the controlled model proposed in this paper is more reasonable and also more effective in the sense that it takes into account the formation of traffic congestion.

关键词： traffic flow coupled map car-following model inter-vehicle communication supernetwork

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