A novel unsupervised framework was developed for constructing a dynamic Health Indicator (HI) for analyzing rolling bearings' degradation and predicting future trends.
The framework includes a degradation feature learning module that uses a skip-connection-based autoencoder to extract essential features from raw signals without expert knowledge.
A new HI-generating module with an inner HI-prediction block captures temporal dependencies between past and current HI states, ensuring effective degradation trend representation and prognostics.
Experiment results on two bearing lifecycle datasets demonstrate the superiority of the proposed dynamic HI construction method for prognostic tasks compared to other methods.