The residual life prediction of the satellite attitude control system based on Petri net

Residual life is widely recognized as the time period that the system can work normally from the current operating conditions until broken. As an important means of system health evaluation, the residual life prediction has become a research hotspot at home and abroad. The residual life of the satellite attitude control system is affected by a variety of factors. In this paper, the concept of degraded state or partial failure is introduced to analyze the influence caused by different failures of the system thoroughly. Five states are defined in this paper numbered from 1 to 5 in consideration of the severity of the failure. There are transitions between states, whose conditional probability can be estimated through Kaplan-Meier estimator and then fitted as parametric Weibull distribution via the Maximum Likelihood Estimation (MLE) approach. The states and the transitions constitute the Petri net model of the satellite attitude control system, on which the residual life can be predicted through a large number of simulations. In the end of the paper, some simulations of specific satellite attitude control system are made given the state of the system, from which we can predict the residual life of the system and the possible state the system may transition to in advance. In this paper, we explore the residual life prediction method in terms of the satellite attitude control system, which will be helpful for making effective mission plans for satellites on orbit.