A Novel Principal Component Analysis Method Guided by Auxiliary Target Signals and its Application to Fault Diagnosis of Flexible Thin-walled Elliptical Bearings
摘要
The flexible thin-walled elliptical bearing (FTEB), a key component of harmonic reducers, produces elliptical periodic impacts that mask fault-induced impulses, rendering conventional diagnostic methods ineffective. This study aims to develop a novel signal processing approach to overcome this limitation and enable accurate weak fault detection in FTEBs.
MethodsA novel auxiliary-signal-guided principal component analysis (PCA) approach is proposed. Unlike traditional PCA and signal decomposition techniques, the method exploits two theoretical properties: (i) each frequency component generates a pair of adjacent nonzero eigenvalues, and (ii) eigenvalue ranking follows amplitude dominance. By injecting a sinusoidal component at the target frequency, the eigenvalue distribution is reshaped, enabling precise localization and separation of weak fault features.
ResultsSimulation results demonstrate the superior capability of the proposed method in isolating single-frequency components. Experimental analysis of FTEB signals confirms accurate extraction of fault characteristic frequencies and their harmonics, free from interference caused by elliptical impacts.
ConclusionThe proposed method provides a robust diagnostic tool with enhanced frequency resolution and feature separation performance, offering new insight into weak fault detection for FTEBs.