abstract = "Slewing bearings are vital functional components of
large machinery. It is of far reaching significance to
study their life prediction and health management. Many
studies are based on data-driven approaches. However,
part of them in the form of {"}black-box{"} lack actual
physical meanings due to opacity model structures and
have difficulty in choosing optimal parameters. Few
kinds of literature focus on explicit model
relationships for slewing bearings' life models. In
this paper, a novel approach based on symbolic
regression is proposed with the aim of exploring
slewing bearings' explicit life models in depth and to
predict residual useful life (RUL). The proposed method
integrates the strengths of multiple signals describing
a comprehensive response to slewing bearings' health
and various genetic programming (GP) algorithms
modeling life expressions. In addition, independent,
hybrid, and piecewise strategies are introduced and
explicit model relationships with respect to
degradation indicators (DIs) are established via GPs.
To verify the proposed method, three run-to-failure
experiments under discrepant operating conditions of
slewing bearings are carried out. Prediction results
demonstrate that models generated by epigenetic linear
genetic programming (ELGP) under hybrid and piecewise
modeling strategy with similarity-based combination
strategy perform best. More importantly, their life
expressions are more succinct and intelligible than in
other situations.",
notes = "School of Mechanical and Power Engineering, Nanjing
Tech University, Nanjing, China