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Comparison of several methods for the notch effect quantification on specimens from 2124-T851 aluminum alloy

Procedia Structural Integrity 2019年 19卷 405-414页

作者： Jan Papuga Adam Karkulín Ondřej Hanžl Maxim Lutovinov U12111 Faculty of Mechanical Engineering Czech Technical University in Prague Technická 4 166 07 Prague 6 Czech Republic Dept. of Instrumentation and Control Engineering Faculty of Mechanical Engineering Center of Advanced Aerospace Technology Czech Technical University in Prague Technicka Street 4 16607 Prague 6 Czech Republic

The paper summarizes several approaches on implementing the notch effect into the fatigue life estimate in high-cycle fatigue region in case of uniaxial fatigue experiments on notched bar specimens. Results of own experiments on specimens prepared from 2124-T851 aluminum alloy (five different notch geometries) are used for the subsequent analyses. The nominal solution derived from the stress concentration factors is compared with the stress gradient approach and the critical distance approach.

关键词： notch effect 2124-T851 aluminum alloy relative stress gradient theory of critical distance high-cycle fatigue

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A novel frequency domain maximum likelihood approach for estimating transport coefficients in cylindrical geometry for nuclear fusion devices

A novel frequency domain maximum likelihood approach for est...

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IEEE Annual Conference on Decision and control

作者： Matthijs van Berkel Gerardus W. Oosterwegel Martijn Anthonissen Hans J. Zwart Gerd Vandersteen DIFFER-Dutch Institute for Fundamental Energy Research Energy Systems and Control group Eindhoven The Netherlands Dept. of Mathematics and Computer Science Eindhoven University of Technology Eindhoven The Netherlands Dept. of Mechanical Engineering Eindhoven University of Technology Eindhoven The Netherlands Dept. of Fundamental Electricity and Instrumentation Vrije Universiteit Brussel (VUB) Brussels Belgium

ISBN: (数字)9781728113982

ISBN: (纸本)9781728113999

This paper introduces a novel maximum likelihood approach to determine the local thermal transport coefficients belonging to diffusion and convection from excitation (perturbative) transport experiments. It extends previous work developed for linear (slab) geometry to cylindrical (toroidal) geometry for fusion reactors. The previous linear geometry approach is based on analytic solutions of the partial differential equation. However, for cylindrical geometries with convection the analytic solutions are confluent hypergeometric functions (CHFs) with complex valued arguments. Most numerical libraries do not support CHFs evaluation with complex valued arguments. Hence, this paper proposes the use of an ultra-fast transfer function evaluation based on sparse numerical solutions for the discretized partial differential equation. This solution is implemented in MATLAB and incorporated in the frequency domain Maximum Likelihood Estimation framework. Consequently, transport coefficients can be estimated consistently when measurements are perturbed by coloured and spatially correlated noise.

关键词： Fusion reactors Geometry Maximum likelihood estimation Temperature sensors Partial differential equations Frequency-domain analysis

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Quantitative analysis of EMG amplitude estimator for surface emg signal recorded during isometric constant voluntary contraction

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Transactions of the Korean Institute of Electrical Engineers 2017年第5期66卷 843-850页

作者： Lee, Jin Dept. of Control and Instrumentation Engineering Kangwon National Univ. Samcheok Korea Republic of

The EMG amplitude estimator, which has been investigated as an indicator of muscle force, is utilized as the control input to artificial prosthetic limbs. This paper describes an application of the optimal EMG amplitude estimator to the surface EMG signals recorded during constant isometric %MVC (maximum voluntary contraction) for 30 seconds and reports on assessing performance of the amplitude estimator from the application. Surface EMG signals, a total of 198 signals, were recorded from biceps brachii muscle over the range of 20-80%MVC isometric contraction. To examine the estimator performance, a SNR(signal-to-noise ratio) was computed from each amplitude estimate. The results of the study indicate that ARV(average rectified value) and RMS(root mean square) amplitude estimation with forth order whitening filter and 250[ms] moving average window length are optimal and showed the mean SNR improvement of about 50%, 40% and 20% for each 20%MVC, 50%MVC and 80%MVC surface EMG signals, respectively. © 2017 The Korean Institute of Electrical Engineers.

关键词： Signal to noise ratio

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Design of High-Speed Permanent Magnet Synchronous Motor for Advanced and Sensorless control Techniques Validation

Design of High-Speed Permanent Magnet Synchronous Motor for ...

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MECHATRONIKA International Symposium

作者： Zdenek Novak Martin Novak Dept. of Instrumentation and Control Engineering CTU in Prague Prague Czech Republic

ISBN: (纸本)9781538643648;9788021455429

This paper presents a design of a high-speed (HS) permanent magnet synchronous motor (PMSM) for advanced and sensorless control techniques validation. First, an electromechanical design of the motor is introduced. It consists of a rotor, a stator core and a motor housing design. FEM software is used for electromagnetic design and two different versions of the stator core are proposed. A key element of the design process is the feasibility of the motor manufacturing using materials available in the market for a single unit production. Therefore, to lower maintenance requirements and motor complexity, the stator core with lower power losses is chosen. To be able to operate the HS PMSM at a nominal speed suitable bearings are selected. For verification of control techniques such as a sensorless control, the motor is equipped with a 12-bit angular Hall encoder. The paper contains an overview of the manufacturing process and a price range of used components as well. After the manufacturing process, the Luenberger observer with quadrature phase locked loop is designed for the sensorless control of HS PMSM. The influence of time delays is reduced with a multisampled PWM and the algorithm is implemented on a FPGA and tested with the manufactured HS PMSM. The experimental results are analyzed for future improvements.

关键词： Rotors Permanent magnet motors Stator cores Synchronous motors Sensorless control Windings Magnetic levitation

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Spectral dominance of complex roots for single-delay linear equations

arXiv

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arXiv 2020年

作者： Mazanti, Guilherme Boussaada, Islam Niculescu, Silviu-Iulian Vyhlídal, Tomáš CentraleSupélec — CNRS — Université Paris-Sud Université Paris-Saclay 3 rue Joliot Curie Gif-sur-Yvette91192 France 63 boulevard de Brandebourg Ivry-sur-Seine94200 France DISCO Team Inria Saclay Dept. of Instrumentation and Control Eng. Faculty of Mechanical Engineering Czech Technical University in Prague Technická 4 Praha 6166 07 Czech Republic

This paper provides necessary and sufficient conditions for the existence of a pair of complex conjugate roots, each of multiplicity two, in the spectrum of a linear time-invariant single-delay equation of retarded type. This pair of roots is also shown to be always strictly dominant, determining thus the asymptotic behavior of the system. The proof of this result is based on the corresponding result for real roots of multiplicity four, continuous dependence of roots with respect to parameters, and a detailed study of crossing imaginary roots. Copyright © 2020, The Authors. All rights reserved.

关键词： Time delay

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An effective auto-focusing method for curved panel inspection system

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Transactions of the Korean Institute of Electrical Engineers 2017年第4期66卷 709-714页

作者： Lee, Hwang-Ju Park, Tae-Hyoung Dept. of Electronics Engineering Chungbuk National University Korea Republic of Dept. of Control and Robot Engineering Chungbuk National University Korea Republic of

The curved panel is widely used for display of TVs and smart phones. This paper proposes a new auto-focusing method for curved panel inspection system. Since the distance between the camera and the panel varies with the curve position, the camera should change its focus at every inspection time. In order to reduce the focusing time, we propose an effective focusing method that considers the mathematical model of panel curve. The Lagrange polynomial equation is applied to modeling the panel curve. The foci of initial three points are used to get the curve equation, and the other foci are calculated automatically from the curve equation. The experiment result shows that the proposed method can reduce the focusing time. Copyright © The Korean Institute of Electrical Engineers.

关键词： Cameras

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Recursive Estimation of Battery Pack Parameters in Electric Vehicles

Recursive Estimation of Battery Pack Parameters in Electric ...

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IEEE International Conference on Computational Intelligence and Computing Research

作者： R Ramachandran B Subathra Seshadhri Srinivasan Dept. of Instrumentation and Control Engineering Kalasalingam Academy of Research and Education Krishnankoil India

ISBN: (纸本)9781538615096

Battery management system (BMS) is an essential component for ensuring safety, reliability and battery life in Electric Vehicle (EV). Estimation of State-of-Charge (SOC) is one of the key functions of BMS in EV. This investigation combines the digital-twin approach and parameter estimation methods to estimate the battery pack's SOC online. The battery's digital-twin is an equivalent circuit model on which simulations are conducted by using current measurements. The model output is used as input to the parameter estimation algorithm which estimates the battery parameters. We provide a novel approach which combines off-line parameter estimation based on least-squares with recursive least squares to update the battery parameters when the vehicle is operating. This provides a way to monitor SoC and provide diagnostics based on current conditions. The proposed approach is illustrated using battery parameters obtained from a EV battery pack. Our results illustrates the efficacy of the approach to provide accurate estimates of parameter and SoC.

关键词： Batteries State of charge Computational modeling Integrated circuit modeling Adaptation models Mathematical model Electronic countermeasures

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An efficient 3D pedestrian detector with calibrated RGB camera and 3D LiDAR

An efficient 3D pedestrian detector with calibrated RGB came...

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2019 IEEE International Conference on robotics and Biomimetics, ROBIO 2019

作者： Pang, Lei Cao, Zhiqiang Yu, Junzhi Liang, Shuang Chen, Xuechao Zhang, Weimin State Key Lab Management and Control for Complex Systems Institute of Automation CAS Beijing100190 China University of Chinese Academy of Sciences Beijing100049 China Dept. Mech. Eng. Sci. BIC-ESAT College of Engineering Peking University Beijing100871 China BAICIRS Beijing100081 China Intell. Robot. Inst. Beijing Inst. Technol. Beijing100081 China

ISBN: (纸本)9781728163215

Pedestrian detection plays an important role in the environmental perception and autonomous navigation for robotics, which provides critical information for the safe operation in complex environments. In this paper, a 3D pedestrian detector with calibrated LiDAR and RGB Camera is proposed, which takes full advantage of the precise range information of 3D LiDAR scanner and semantic information acquired from RGB image. The proposed approach integrates the segmented object clusters of point cloud and 2D bounding boxes generated by a visual object detector. The point cloud is segmented by a three-step segmentation approach, which can segment point cloud with both high precision and high efficiency. By fusion multi-sensor information in the image domain, the proposed approach provides 3D information of pedestrians in both LiDAR and camera coordinate systems. Experiments was conducted to evaluate the performance of the proposed approach. © 2019 IEEE.

关键词： Cameras

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Oscillation Detection in control Loops using PRONY Analysis

Oscillation Detection in Control Loops using PRONY Analysis

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International Conference on Computational and Characterization Techniques in engineering & Sciences (CCTES)

作者： Sachin Sharma Vineet Kumar K.P.S. Rana Dept. of Instrumentation & Control Engineering Netaji Subhash Institute of Technology New Delhi India

ISBN: (纸本)9781538642559;9781538642542

Oscillations in process control loops present a serious threat to normal functioning of plant as they lead to product quality variations, fast wear and tear of plant components, possible loss of human lives and property. As a result, overall profitability of the plant gets compromised. To cater to these issues automatic detection of plant wide control loop oscillations is a top most priority for control engineers and industrial consultants. In this work a new automatic oscillation detection algorithm has been proposed based on Prony method for time domain design of infinite impulse response (IIR) filter. In this method IIR filter is designed with time domain impulse response same as the input data. Further, oscillations in the control loop were detected based on the location of IIR filter poles on z-plane. Performance of the proposed algorithm was evaluated for oscillation detection for simulated data, real plant data and industrial plant data. Proposed algorithm was successfully able to detect oscillations in all the cases.

关键词： Oscillators IIR filters Detection algorithms Mathematical model Process control Time-domain analysis Market research

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Spectral dominance of complex roots for single-delay linear equations

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IFAC-PapersOnLine 2020年第2期53卷 4357-4362页

作者： Guilherme Mazanti Islam Boussaada Silviu-Iulian Niculescu Tomáš Vyhlídal University Paris-Saclay CNRS CentraleSupélec Laboratoire des Signaux et Systèmes (L2S) Inria Saclay DISCO Team 3 rue Joliot Curie 91192 Gif-sur-Yvette France Institut Polytechnique des Sciences Avancées (IPSA) 63 boulevard de Brandebourg 94200 Ivry-sur-Seine France Dept. of Instrumentation and Control Eng. and Center of Advanced Aerospace Technology Faculty of Mechanical Engineering Czech Technical University in Prague. Technická 4 166 07 Praha 6 Czechia

This paper provides necessary and sufficient conditions for the existence of a pair of complex conjugate roots, each of multiplicity two, in the spectrum of a linear time-invariant single-delay equation of retarded type. This pair of roots is also shown to be always strictly dominant, determining thus the asymptotic behavior of the system. The proof of this result is based on the corresponding result for real roots of multiplicity four, continuous dependence of roots with respect to parameters, and the study of crossing imaginary roots. We also present how this design can be applied to vibration suppression and flexible mode compensation.

关键词： Time-delay equations stability analysis spectral methods root assignment crossing imaginary roots

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