Utilizing VQ-VAE for End-to-End Health Indicator Generation in
  Predicting Rolling Bearing RUL
Junliang Wang Qinghua Zhang Guanhua Zhu Guoxi Sun
The prediction of the remaining useful life (RUL) of rolling bearings is a
pivotal issue in industrial production. A crucial approach to tackling this
issue involves transforming vibration signals into health indicators (HI) to
aid model training. This paper presents an end-to-end HI construction method,
vector quantised variational autoencoder (VQ-VAE), which addresses the need for
dimensionality reduction of latent variables in traditional unsupervised
learning methods such as autoencoder. Moreover, concerning the inadequacy of
traditional statistical metrics in reflecting curve fluctuations accurately,
two novel statistical metrics, mean absolute distance (MAD) and mean variance
(MV), are introduced. These metrics accurately depict the fluctuation patterns
in the curves, thereby indicating the model's accuracy in discerning similar
features. On the PMH2012 dataset, methods employing VQ-VAE for label
construction achieved lower values for MAD and MV. Furthermore, the ASTCN
prediction model trained with VQ-VAE labels demonstrated commendable
performance, attaining the lowest values for MAD and MV.