“…This means that the detection of periodic impulses related to bearing faults is an effective way right now to achieve reliable fault diagnosis of rolling element bearing, which are usually divided into two categories (i.e., the resonance demodulation-based and signal decomposition-based method). The existing resonance demodulation-based methods mainly contain the indicator-assisted deconvolution techniques (e.g., minimum entropy deconvolution (MED), 6 maximum correlated kurtosis deconvolution (MCKD), 7 maximum average kurtosis deconvolution (MAKD), 8 sparse maximum harmonics-to-noise-ratio deconvolution (SMHD), 9 maximum second-order cyclostationarity blind deconvolution (CYCBD) 10 ) and the kurtogram tools (e.g., spectral kurtosis (SK), 11 infogram, 12 autogram, 13 and accugram 14 ), while the current published signal decomposition-based methods have wavelet packet decomposition (WPT), 15 empirical mode decomposition (EMD), 16 local mean decomposition (LMD), 17 local characteristic-scale decomposition (LCD), 18 ensemble empirical mode decomposition (EEMD), 19–21 empirical wavelet transform (EWT), 22 adaptive local iterative filtering (ALIF), 23 symplectic geometry mode decomposition (SGMD), 24 optimal swarm decomposition (OSD), 25 adaptive chirp mode decomposition (ACMD), 26 singular spectrum decomposition (SSD), 27 variational mode decomposition (VMD), 28–32 and its lately variants named variational mode extraction (VME) 33 and successive variational mode decomposition (SVMD) 34 with the similar theory basis of VMD. Among these methods, whether they be the deconvolution techniques or signal decomposition methods, the effectiveness of both the corresponding original algorithm and its improved version has been experimentally demonstrated in extracting the periodic impulse signatures.…”