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Method of gearbox fault diagnosis based on covariance matrix manifold entropy feature

Journal of Information and Computational Science 2015年第17期12卷 6299-6310页

作者： Wang, Shoubin Li, Chengwei Xu, Yonghong School of Control and Mechanical Engineering Tianjin Chengjian University Tianjin China School of Electrical Engineering and Automation Harbin Institute of Technology Harbin China Institute of Electrical Engineering Yanshan University Qinhuangdao China

For a complex vibration signal, the traditional sample entropy hardly quantifies itself inherent long-range correlation. The multivariate multi-scale entropy is a reflection of the nonlinear dynamic correlation as the promotion of multi-scale entropy in multivariable signal. Applying the improved multivariate multiscale entropy, all variables can be embedded at the same time instead of the individual variable embedded mode in traditional multivariate multi-scale entropy. It not only solves the problem of memory overflow with the increasing channel number, but also is appropriate for the actual multivariable signal analysis. This paper analyzed the four-type signals, which were ones in normal operation, brokenperforation, mild wear and moderate wear of gear box. The experimental result showed that this method has a good performance to distinguish the correlation data and the fault diagnosis precision reached 98.4%. © 2015 by Binary Information Press.

关键词： Failure analysis

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A novel approach for classification of congestive heart failure using relatively short-term ECG waveforms and SVM Classifier

A novel approach for classification of congestive heart fail...

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International MultiConference of Engineers and Computer Scientists 2015, IMECS 2015

作者： Liao, Ken Ying-Kai Chiu, Chuang-Chien Yeh, Shoou-Jeng Ph.D. Program of Electrical and Communications Engineering Feng-Chia University Taichung Taiwan Department of Automatic Control Engineering Feng-Chia University Taichung Taiwan Section of Neurology and Neurophysiology Cheng-Ching General Hospital Taichung Taiwan

ISBN: (纸本)9789881925329

In this study, a novel approach for assessing congestive heart failure by using support vector machine (SVM) and relatively short-term ECG waveforms is presented. This approach only involved a simple data normalization, resampling, and repetition of periodic data in order to obtain a good accuracy while still being a good general classifier. The ECG unit patterns were first consecutively extracted from the ECG signal. Then the unit patterns were inputted into a support vector machine for classification. Stacking three unit patterns obtained the most general classifier, while stacking five unit patterns achieved the best accuracy. In conclusion, by introducing an extra periodic pattern into the SVM, it is possible to both in-crease the accuracy and generality of the classifier. This makes short waveform classification possible, rather than looking at long trends.

关键词： Electrocardiograms

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Novel multi-interface USB prototype device for merging commonly used peripheral devices

Novel multi-interface USB prototype device for merging commo...

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International Conference on Industrial Instrumentation and control (ICIC)

作者： Siddharth Kaul Parth Maheta R J Rajesh Rashmi Ranjan Das Control and Automation School of Electrical Engineering VIT University Vellore Tamil Nadu Robotics and Control Division School of Electrical Engineering VIT University Vellore Tamil Nadu

The Universal Serial Bus (USB) Specification allows combination of different USB components into a single device. This creates a composite device and each component is recognized as an independent device. The aim of the paper is to introduce a novel concept to combine some commonly used USB classes in a single device to create a composite device that functions in multiple ways. The paper shows some ways of combining two different USB classes using available Real Time Operating System (RTOS). The paper explains the implementation of USB Human Interface Device class and USB Mass Storage Device the classes used in the two most commonly used peripheral devices, using available stack libraries and clearly explains the important aspects in implementing the said classes. The prototype device mentioned will function both as a pointing device and a storage device.

关键词： Robots Universal Serial Bus Mice Ice

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Measurement of Phase Fraction in Oil-Water Two-Phase Flow Using Ultrasound Attenuation Method

Measurement of Phase Fraction in Oil-Water Two-Phase Flow Us...

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Chinese automation Congress

作者： Qian Su Chao Tan Feng Dong Key Laboratory of Process Measurement and Control School of Electrical Engineering and Automation Tianjin University

ISBN: (纸本)9781467371902

Ultrasonic technology has potential application prospect in measurement of phase fraction in oil-water two-phase flow. An ultrasound attenuation method is discussed in the oil-water two-phase flow. Geometric simulation models of oil-water two-phase flow with different fractions are set up based on the finite element analysis method. Simulation results show that phase fraction and distribution jointly affect on the ultrasound attenuation coefficient. Test results give good agreement with the trend of the simulation results. The feasibility and effectiveness can be achieved to use the ultrasound attenuation testing method. This is a basic work for ultrasound attenuation method adopted to test the phase fraction of oil-water two-phase flow. A predicted model of phase fraction with different flow patterns can be effectively established combined with physically experimental data.

关键词： Ultrasonic sensor Oil-water two-phase flow Phase fraction Ultrasound attenuation Flow parameter

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Unified Generating and Storing Capacity Reliability Evaluation in Nearly-Zero Energy Buildings

Unified Generating and Storing Capacity Reliability Evaluati...

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IEEE Power and Energy Society General Meeting

作者： Pablo Arboleya Edwin Xavier Dominguez Felix Manuel Lorenzo Department of Electrical Engineering University of Oviedo Control and Automation Department National Politechnic School

ISBN: (纸本)9781467380416

This paper presents a methodology for developing an adequacy assessment of the generating and storing mix capacity in nearly-Zero Energy Residential Buildings (nZEB). The adequacy of a given generating and storing mix will be quantified by means of a set of reliability indices obtained by adapting the traditional reliability techniques employed in power systems. The analysis will use a Montecarlo based sampling, to obtain the hourly load and generation profiles of the buildings. Then, the obtained profiles will be used together with the building management system (BMS) model and the energy storage system (ESS) model for obtaining the desired reliability indices.

关键词： Adequacy assessment Reliability evaluation Nearly-Zero Energy Buildings Montecarlo

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Wiener Recurrent Neural Network Adaptive Inverse controller of Hydraulic Flight Motion Simulator

Wiener Recurrent Neural Network Adaptive Inverse Controller ...

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2015 International Conference on Fluid Power and Mechatronics

作者： Zhao Yifei Jiao Zongxia Wu Shuai School of Automation Science and Electrical Engineering Science and Technology on Aircraft Control Laboratory BUAA

The traditional control strategy of hydraulic flight motion simulator(HFMS) cannot meet the high tracking performance requirement, and the control precision is sensitive to disturbance. This paper presents an adaptive inverse controller based on the Wiener-type recurrent neural network(WRNN) to deal with the parametric uncertainties and uncertain nonlinearities in HFMS. The WRNN is a dynamic linear subsystem cascaded with a static nonlinear subsystem. The controller contains two WRNNs, one to identify the Jacobian information of the controlled plant and another to approximate the inverse model of the plant. Since the inverse transfer function behaves sensitive to the initial value, a feedback controller is designed. The input of the controlled plant includes the feedback controller output and the WRNN inverse controller output. Simulations have confirmed the effectiveness and superiority of the proposed WRNN adaptive inverse control strategy.

关键词： Wiener recurrent neural network adaptive control inverse control system identification

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Active Fault Diagnosis in Sampled-data Systems

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IFAC-PapersOnLine 2015年第21期48卷 883-888页

作者： Niemann, Henrik Poulsen, Niels Kjolstad Department of Electrical Engineering Automation and Control Technical University of Denmark Building 326 DK-2800 Kgs. Lyngby Denmark Dept. of Applied Mathematics and Computer Science Section for Dynamical Systems Technical University of Denmark DK-2800 Kgs. Lyngby Denmark

The focus in this paper is on active fault diagnosis (AFD) in closed-loop sampleddata systems. Applying the same AFD architecture as for continuous-time systems does not directly result in the same set of closed-loop matrix transfer functions. For continuous-time systems, the LFT (linear fractional transformation) structure in the connection between the parametric faults and the matrix transfer function (also known as the fault signature matrix) applied for AFD is not directly preserved for sampled-data system. As a consequence of this, the AFD methods cannot directly be applied for sampled-data systems. Two methods are considered in this paper to handle the fault signature matrix for sampled-data systems such that standard AFD methods can be applied. The first method is based on a discretization of the system such that the LFT structure is preserved resulting in the same LFT structure in the fault signature matrix as obtained for continuous-time systems. The other method is an approximation method, where the same structure is obtained for small parametric faults. © 2015

关键词： Continuous time systems

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Early pack-off diagnosis in drilling using an adaptive observer and statistical change detection 2

Early pack-off diagnosis in drilling using an adaptive obser...

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2nd IFAC Workshop on Automatic control in Offshore Oil and Gas Production, OOGP 2015

作者： Willersrud, Anders Imsland, Lars Blanke, Mogens Department of Engineering Cybernetics Norwegian University of Science and Technology TrondheimN-7491 Norway Automation and Control Group Department of Electrical Engineering Technical University of Denmark Kgs. LyngbyDK-2800 Denmark AMOS Centre of Excellence Department of Engineering Cybernetics Norwegian University of Science and Technology TrondheimN-7491 Norway

Pack-off is a partially or complete blocking of the circulation flow in oil and gas drilling, which can lead to costly delays. Early detection and localization of a pack-off is crucial in order to take necessary actions avoiding downtime. This incident will affect physical friction parameters in the well. A model-based adaptive observer is used to estimate these friction parameters as well as flow rates. Detecting changes to these estimates can then be used for pack-off diagnosis, which due to measurement noise is done using statistical change detection. Isolation of incident type and location is done using a multivariate generalized likelihood ratio test, determining the change direction of the estimated mean values. The method is tested on simulated data from the commercial high-fidelity multi-phase simulator OLGA, where three different pack-offs at different locations and with different magnitudes are successfully detected at an early stage and with low false alarms. © 2015, IFAG (International Federation of Automatic control) Hosting by Elsevier Ltd. All rights reserved.

关键词： Fault detection

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MEMS based microswitch and microrelay

MEMS based microswitch and microrelay

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International Conference on Industrial Instrumentation and control (ICIC)

作者： R J Rajesh Siddharth Kaul Parth Maheta Sachin M C Control and Automation School of Electrical Engineering VIT University Vellore Tamil Nadu India Robotics and Control School of Electrical Engineering VIT University Vellore Tamil Nadu India

Today in market miniature devices are gaining extreme popularity. The use of MEMS based devices is seeing a rapid growth and finds applications in wide range of commercial and defense applications. MEMS switches may be of thin metal cantilever, air bridge, diaphragm or some other structure which is electrically configured either in series or parallel with RF transmission line. These switches are designed to open the line or shunt it to ground upon actuation. These switches have showed excellent RF characteristics which include insertion loss values of 0.1dB, isolation values of -30dB when switches are in series configuration at low RF frequencies (VHF to ~10GHz) and in switches of shunt configuration at higher frequencies (~10 to 100GHz). This type of response enables excellent performance in traditional RF circuits, capacitor banks and routing in RF system. It can also be said that RF MEMS enables a new class of antenna system which can be electrically reconfigured. In all these applications traditional switches can be replaced by RFMEMS switches. In this work, we have designed cantilever based MEMS switches and relay which operates at different voltages and for different dimensions. The design, modeling and simulation are done by FEM technique which is inbuilt in COMSOL. The tool used for this modeling is Comsol/Multiphysics.

关键词： Relays Micromechanical devices Contacts Solid modeling Microswitches Bridge circuits

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Discrete Sliding Mode control for a Non-minimum Phase Electro-hydraulic Actuator System

Discrete Sliding Mode Control for a Non-minimum Phase Electr...

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Asian control Conference

作者： R. Ghazali Y. M. Sam M. F. Rahmat C. C. Soon H. I. Jaafar Zulfatman Center for Robotics and Industrial Automation Faculty of Electrical Engineering Universiti Teknikal Malaysia Melaka Department of Control and Mechatronics Engineering Faculty of Electrical Engineering Universiti Teknologi Malaysia

ISBN: (纸本)9781479978632

The main objective of this paper is to perform a robust controller design using discrete-time sliding mode control (DSMC). In the control scheme, two-degree-of-freedom (2-DOF) control strategy turns the DSMC, which generally utilized state feedback into output feedback controller. The designed control scheme is considered with feedback and feedforward combination by implementing the zero phase error tracking control (ZPETC), which particularly intended for the nonminimum phase electro-hydraulic actuator (EHA) system application. In the experimental works, a sinusoidal trajectory with different frequencies is employed to assess the DSMC performance under nonlinear and uncertain condition. Experimental results show the DMSC with perfect tracking control approach is capable to reduce the phase lag occurred due to nonlinear phenomenon. The proposed controller also is highly robust under various points of trajectories and significantly shows enhancement in tracking control performance as compared to the conventional controllers.

关键词： Output feedback control Discrete sliding mode control Zero-phase-error-tracking control Electro-hydraulic actuator system

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