Authors: Milan Chlada; Zdenek Prevorovsky
Addresses: NDT Department, Institute of Thermomechanics AS CR, v.v.i., Dolejskova 1402/5, 182 00 Praha 8, Czech Republic. ' NDT Department, Institute of Thermomechanics AS CR, v.v.i., Dolejskova 1402/5, 182 00 Praha 8, Czech Republic
Abstract: Accurate acoustic emission (AE) source location is the primary goal of the defect analysis following the AE signal detection. The source localisation is mostly based on arrival time differences of signals detected by several transducers. Considerable signal distortion occurs during the wave propagation through the body. Inaccurate determination of signal onsets and arrival time differences, consequently, are the greatest sources of localisation errors. Especially, in a case of higher requirements on accuracy and robustness (e.g., small sensor distances or elevated background noise), the results of currently used localisation methods are unsatisfactory. In this paper, an improved version of the wave arrival detection algorithm emulating an expert system is introduced. The new algorithm is based on signal waveform analysis taking into account the signal energy and trend of local gravity centre. The method has been proved in many applications as reliable enough, fast and easily implemented.
Keywords: acoustic emission; AE; source location; signal arrival detection; expert systems; signal waveform analysis.
International Journal of Microstructure and Materials Properties, 2011 Vol.6 No.3/4, pp.191 - 205
Available online: 20 Oct 2011 *Full-text access for editors Access for subscribers Purchase this article Comment on this article