The local mean decomposition method and its application to gear fault diagnosis

A newly self-adaptive time-frequency analysis method,the local mean decomposition(LMD) is studied in the paper.Aiming at the modulated features of the gear fault vibration signal,the gear fault diagnosis method based on LMD is proposed.By using LMD,any complicated signal can be decomposed into a number of product functions whose instantaneous frequencies own physical sense and the integrity time-frequency distribution of the original signal can be obtained.In nature,the multi-component signal can be decomposed into a number of single-component amplitude-modulated and frequency-modulated signals by LMD.In this paper,the LMD method is introduced,then compared with EMD method and the results show the superiority of the LMD method.Furthermore,the LMD method is applied to the gear fault diagnosis.The analysis results from the actual gear fault vibration signal demonstrate that the LMD method can be applied to the gear fault diagnosis effectively.