A method for analysing gearbox faults using time-frequency representations

Gearbox faults are analysed using time-frequency (TF) representations. First, a three-step TF analysis method is introduced, consisting of: (1) calculation of the TF representation; (2) physical interpretation of the main components observed; and (3) model building and validation. Gear and bearing faults are addressed. Physical interpretation of the vibration signals leads to a gearbox model which distinguishes and localises two types of structures: non-linear time-varying structures covering all moving parts, and linear time-invariant structures describing the non-mobile casing. (C) 1997 Academic Press Limited.