Rolling bearings are the key components of rotating machinery. However, the incipient fault characteristics of
a rolling bearing vibration signal are weak and difficult to extract. To solve this problem, this paper presents
a novel rolling bearing vibration signal fault feature extraction and fault pattern recognition method based on
variational mode decomposition (VMD), permutation entropy (PE) and support vector machines (SVM). In the
proposed method, the bearing vibration signal is decomposed by VMD, and the intrinsic mode functions (IMFs)
are obtained in different scales. Then, the PE values of each IMF are calculated to uncover the multi-scale intrinsic
characteristics of the vibration signal. Finally, PE values of IMFs are fed into SVM to automatically accomplish
the bearing condition identifications. The proposed method is evaluated by rolling bearing vibration signals. The
results indicate that the proposed method is superior and can diagnose rolling bearing faults accurately.