Interval statistic based reliability analysis method on small sample hot test of satellite thruster

Abstract

• Propose an interval statistic based reliability analysis method fulfilling the life information from the failure time to the censored time. • Improve the reliability assessment accuracy of satellite thrusters obviously. • Conducted the coating test under different thermal conditions. • Conducted reliability assessment and life prediction of the satellite thruster in both transfer and synchronous orbit phases. As one of the most important components of satellites, the thruster must maintain high reliability, but the assessment is difficult when lacking test failure data. When conducting hot test of the satellite thruster, we encountered the problem of reliability assessment on type-I censored data with only one failure, which is common for small sample tests. This paper proposes a novel interval statistic based reliability analysis method, which can fulfill the life information from the failure time to the censored time ignored by conventional methods, and improve the assessment accuracy. In this paper, a life distribution model is established by proper failure mechanism analysis and prior test information exploitation. As thrust chamber burning-through has been considered as the main failure mode, life test of the chamber coating was conducted under different thermal conditions to obtain the model parameter. Based on the interval statistic theory, a detailed derivation is illustrated. Then, reliability assessment and life prediction for the satellite thruster in both transfer orbit phase and synchronous orbit phase have been achieved, and the results show that our method performs very well, which provides an important way for dealing with test data with only one failure.