Review of Techniques for Fault Diagnosis in Damaged Structure and Engineering System

Dhirendra Nath Thatoi,Dayal R Parhi,Harish Ch Das

doi:10.1155/2012/327569

Abstract

Focus has been made to give an overview of various methodologies used in fault diagnosis and condition monitoring. A crack in vibrating structures can lead to premature failure if it is not detected in time. Researchers have been working on the dynamics of cracked structures for decades to be able to monitor a structure and diagnose fault at the earliest possible stage. An effort has been made in the current paper to understand different techniques and methodologies for fault diagnosis and condition monitoring of damaged structures subjected to varied dynamic loading. The methods used are classical, wavelet transform, and finite element methods, artificial intelligence methods, and numerical and experimental methods. Using classical methods, engineers are able to predict faults. But using artificial intelligence techniques, it is observed that the forecasting time for fault diagnosis improves a lot in comparison to other methodologies.

Highlights

Engineering structures fail in their long working lives from initiation and subsequent growth of faults to catastrophic levels
In the present review of methodologies used for fault diagnosis of vibrating cracked structures and condition monitoring of machineries and structural systems, it is observed that the proposed techniques may be broadly divided into the following categories: (i) classical method, (ii) wavelet transform and finite element method (FEM), (iii) artificial intelligence (AI) techniques, (iv) numerical and experimental techniques
Various methodologies based on the dynamic response and stiffness of the structures have been reviewed for fault diagnosis, and the application of the proposed techniques has been described

Summary

Introduction

Engineering structures fail in their long working lives from initiation and subsequent growth of faults to catastrophic levels. The crack location and crack size have been determined by Shen and Taylor [10] utilizing the dynamic measurement This technique is based on the minimization of either the “mean-square” or “max” of the difference between the measured value of the vibration signature (natural frequency and mode shapes) and corresponding predications obtained from computational model. This technique is in good agreement with experimental results. The damaged location, detection and its severity have been investigated by Cawley and Adams [11] by measuring the structural natural frequencies at the single point of the structure This method has been adopted for any structure utilizing Finite Element Analysis.

Review of Various Methodologies for Fault Diagnosis

Discussions

Findings

Conclusions