Fault diagnosis of RV reducers based on sparrow search algorithm

YANG Ji; YANG Shuqing; FAN Ying; ZHOU Decai

doi:10.16578/j.issn.1004.2539.2025.12.017

Abstract：[Objective]Due to its complex internal composition and numerous components,RV reducer is operated under complex working conditions with fluctuations in speed and direction,resulting in traditional spectral analysis being ineffective in diagnosing faults in the collected time-domain vibration signals.Therefore,an order tracking analysis method was propose based on sparrow search algorithm(SSA)combined with variational mode decomposition(VMD).[Methods]Firstly,the collected time-domain vibration signal and rotational speed signal were integrated by angle and divided into equal angular domains to obtain the equal angular domain vibration signal.Then,the optimized sparrow search algorithm was used,with multi-scale permutation entropy(MPE)as the fitness function,to optimize the relevant parameters of the variational mode decomposition,obtaining the optimal decomposition layer number.At the same time,the equal angular domain signal was decomposed to obtain a series of intrinsic mode functions(IMF).Then,according to the maximum kurtosis value criterion,the kurtosis values of each decomposed mode were calculated,and the suitable target components were selected.Finally,the fast Fourier transform(FFT)was used to obtain the order diagram of the RV reducer's fault signal.Test verification was conducted using an RV reducer with damaged needle rollers as an example.[Results]The results show that this method can extract the fault orders from the variable speed test of RV reducers and clearly locate the fault points at low orders,providing reference for the fault diagnosis of RV reducers under variable speed conditions.