Journal of Systems Engineering and Electronics ›› 2021, Vol. 32 ›› Issue (4): 971-983.doi: 10.23919/JSEE.2021.000083

• RELIABILITY • Previous Articles     Next Articles

Reliability modeling of the bivariate deteriorating product with both monotonic and non-monotonic degradation paths

Fuqiang SUN1,2,*(), Hongxuan GUO1,2(), Jingcheng LIU3()   

  1. 1 School of Reliability and Systems Engineering, Beihang University, Beijing 100191, China
    2 Science and Technology on Reliability and Environmental Engineering Laboratory, Beihang University, Beijing 100191, China
    3 Wuhan Maritime Communication Research Institute, Wuhan 430079, China
  • Received:2020-04-12 Online:2021-08-18 Published:2021-09-30
  • Contact: Fuqiang SUN;;
  • About author:|SUN Fuqiang was born in 1983. He received his Ph.D. degree from Beihang University in 2012. From 2015 to 2016, he was a visiting scholar at the University of Arkansas, in America. He is currently an associate professor in the School of Reliability and Systems Engineering at Beihang University, China. His research interests include competing failure risk modeling and multivariate dependent accelerated degradation model. E-mail:||GUO Hongxuan was born in 1991. He received his B.S. degree from the University of Science and Technology Beijing in 2015. He is now a postgraduate student in the School of Reliability and Systems Engineering at Beihang University. His research interests include the reliability analysis and the design of accelerated degradation testing. E-mail:||LIU Jingcheng was born in 1991. She received her M.S. degree from Beihang University, in 2017. She is now an engineer in Wuhan Maritime Communication Research Institute. Her research interests include reliability and life testing. E-mail:
  • Supported by:
    This work was supported by the National Key R&D Program of China (2018YFB0104504).


Fiber optical gyroscope (FOG) is a highly reliable navigation element, and the degradation trajectories of its two accuracy indexes are monotonic and non-monotonic respectively. In this paper, a flexible accelerated degradation testing (ADT) model is used for analyzing the bivariate dependent degradation process of FOG. The time-varying copulas are employed to consider the dynamic dependency structure between two marginal degradation processes as the Wiener process and the inverse Gaussian process. The statistical inference is implemented by utilizing an inference function for the margins (IFM) approach. It is demonstrated that the proposed method is powerful in modeling the joint distribution with various margins.

Key words: fiber optical gyroscope, bivariate accelerated degradation testing, Wiener process, inverse Gaussian process, time-varying copulas, dependence