Fault diagnosis in gears operating under non-stationary rotational speed using polar wavelet amplitude maps

Abstract

This paper will attempt to analyse the effectiveness of the Continuous Wavelet Transform in vibro-acoustical diagnostics of gearboxes operating under non-stationary rotational speed. For this, a simple PC-software program for signal processing and extraction of diagnostic features was developed and tested. The objective of the program test is fault-detection, localisation, and assessment at helical spur gears. This includes improvements of the visual estimation of the WT-plots, especially by the task-specific balance of time- and frequency-resolution and by the display of the wavelet amplitude versus the rotational angle in polar coordinates. The following examples demonstrate the improvements in the detection of gear faults. © 2004 Elsevier Ltd. All rights reserved.