Gear Defect through Hilbert–Huang Transform Analysis of Gearbox Vibration Signals

Abstract

Targeting the feature extraction of the gear fault vibration, Hilbert–Huang transform (HHT) analysis is introduced into the gear fault diagnosis in rotating machinery. The concept of the instantaneous energy in time-frequency analysis, based on Hilbert time-frequency spectrum, was used to measure the energy distribution of the signal in time-frequency domain. The gear vibration signal is decomposed into a series of intrinsic mode functions (IMFs), which are band limited and the frequency families are separated effectively according to the signal characteristics with empirical mode decomposition. The fault feature of the gear vibration signal can be extracted effectively from Hilbert time-frequency spectrum which can represent the instantaneous frequency of the gear vibration signal with the change of the time. The analysis results from the experimental vibration signal show that HHT analysis can extract the character.