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David J. Ewins

Bio: David J. Ewins is an academic researcher from Imperial College London. The author has contributed to research in topics: Vibration & Modal analysis. The author has an hindex of 50, co-authored 275 publications receiving 12281 citations. Previous affiliations of David J. Ewins include Queen Mary University of London & University of Surrey.


Papers
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Book
01 Dec 1984
TL;DR: A survey of the technology of modal testing, a new method for describing the vibration properties of a structure by constructing mathematical models based on test data rather than using conventional theoretical analysis.
Abstract: A survey of the technology of modal testing, a new method for describing the vibration properties of a structure by constructing mathematical models based on test data rather than using conventional theoretical analysis. Shows how to build a detailed mathematical model of a test structure and analyze and modify the structure to improve its dynamics. Covers techniques for measuring the mode, shapes, and frequencies of practical structures from turbine blades to suspension bridges.

2,525 citations

Book
01 Nov 1998

2,477 citations

Journal ArticleDOI
TL;DR: In this article, a numerical algorithm based on the harmonic balance method was proposed to calculate the periodic response of a non-linear system under periodic excitation, and the algorithm also calculated the stability of the periodic solutions found, marks turning and bifurcation points, and follows a solution branch over varying system parameters via arc-length continuation.

325 citations

Journal ArticleDOI
TL;DR: The 6DOF set showed comparable performance to the conventional set and overcomes a number of theoretical limitations, however further development is needed prior to clinical implementation.

292 citations

Journal ArticleDOI
TL;DR: In this paper, a simplified model is used to study the implications of this real situation from a consideration of the vibration levels which these components might suffer in practice, and an optimum arrangement of typical blades is proposed.

273 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, the authors provide an overview of methods to detect, locate, and characterize damage in structural and mechanical systems by examining changes in measured vibration response, including frequency, mode shape, and modal damping.
Abstract: This paper provides an overview of methods to detect, locate, and characterize damage in structural and mechanical systems by examining changes in measured vibration response. Research in vibration-based damage identification has been rapidly expanding over the last few years. The basic idea behind this technology is that modal parameters (notably frequencies, mode shapes, and modal damping) are functions of the physical properties of the structure (mass, damping, and stiffness). Therefore, changes in the physical properties will cause detectable changes in the modal properties. The motivation for the development of this technology is presented. The methods are categorized according to various criteria such as the level of damage detection provided, model-based versus non-model-based methods, and linear versus nonlinear methods. The methods are also described in general terms including difficulties associated with their implementation and their fidelity. Past, current, and future-planned applications of this technology to actual engineering systems are summarized. The paper concludes with a discussion of critical issues for future research in the area of vibration-based damage identification.

2,715 citations

Book
13 Apr 2000
TL;DR: In this paper, the authors discuss the application of metal cutting to manufacturing problems, including the design of real-time trajectory generation and interpolation algorithms, and CNC-oriented error analysis.
Abstract: Metal cutting is a widely used method of producing manufactured products. The technology of metal cutting has advanced considerably along with new materials, computers, and sensors. This new edition treats the scientific principles of metal cutting and their practical application to manufacturing problems. It begins with metal cutting mechanics, principles of vibration, and experimental modal analysis applied to solving shop floor problems. Notable is the in-depth coverage of chatter vibrations, a problem experienced daily by manufacturing engineers. The essential topics of programming, design, and automation of CNC (computer numerical control) machine tools, NC (numerical control) programming, and CAD/CAM technology are discussed. The text also covers the selection of drive actuators, feedback sensors, modeling and control of feed drives, the design of real time trajectory generation and interpolation algorithms, and CNC-oriented error analysis in detail. Each chapter includes examples drawn from industry, design projects, and homework problems. This book is ideal for advanced undergraduate and graduate students, as well as practicing engineers.

1,854 citations

Journal ArticleDOI
TL;DR: A comprehensive review on modal parameter-based damage identification methods for beam- or plate-type structures is presented in this paper, and the damage identification algorithms in terms of signal processing are discussed.
Abstract: A comprehensive review on modal parameter-based damage identification methods for beam- or plate-type structures is presented, and the damage identification algorithms in terms of signal processing...

1,613 citations

Journal ArticleDOI
TL;DR: In this article, the state of the art in vibration-based condition monitoring with particular emphasis on structural engineering applications is reviewed, focusing on the use of in situ non-destructive sensing and analysis of system characteristics for detecting changes, which may indicate damage or degradation.
Abstract: Vibration based condition monitoring refers to the use of in situ non-destructive sensing and analysis of system characteristics –in the time, frequency or modal domains –for the purpose of detecting changes, which may indicate damage or degradation. In the field of civil engineering, monitoring systems have the potential to facilitate the more economical management and maintenance of modern infrastructure. This paper reviews the state of the art in vibration based condition monitoring with particular emphasis on structural engineering applications.

1,394 citations

Journal ArticleDOI
TL;DR: In this paper, a novel approach of stochastic subspace identification is presented that incorporates the idea of the reference sensors already in the identification step: the row space of future outputs is projected into the rowspace of past reference outputs.

1,236 citations