Selection of a mother wavelet as identification pattern for the detection of cracks in shafts Articles uri icon

publication date

  • June 2021

start page

  • 1

end page

  • 10

International Standard Serial Number (ISSN)

  • 1077-5463

Electronic International Standard Serial Number (EISSN)

  • 1741-2986

abstract

  • Nowadays, there are many methods to detect and diagnose defects in mechanical components during operation. The newest methods that can be found in the literature are based on intelligent classification systems and evaluation of patterns to obtain a diagnosis; however, there is not any standard method to assess features. Wavelet packet transform allows to obtain interesting patterns for evaluating the condition of rotating elements. To perform this calculation, it is necessary to select a series of parameters that affect the resulting pattern. These parameters are the decomposition level and the mother wavelet function. A detailed methodology for the selection of the mother wavelet is proposed, which is the aim of this work, to obtain the most suitable patterns in the diagnostic task. This proposed methodology is applied to data obtained from a rotating shaft with a crack located at the change of section. These signals were measured at low rotation frequency (below the critical rotation frequency) and without eccentricity, where detection becomes more complex.

keywords

  • mother wavelet; wavelet packet transform; vibration analysis; condition monitoring; shaft crack diagnosis