Phased System Reliability Modeling and Assessment for Construction of Lunar Scientific Base

The construction of a lunar scientific base (LSB) is a complex and gradual process that has to be completed in stages according to mission planning. Reliability assessment is critical for quantifying failure risks and planning complex space missions. In space engineering, reliability tests often encounter small samples and zero-failure data, rendering traditional system reliability assessment methods based on maximum likelihood theory inapplicable. This paper introduces a novel reliability assessment method for phased systems, termed building block assessment (BBA), to address existing limitations. The approach involves the development of a phased reliability model, which avoids correlation issues in reliability analysis. The reliability of the phased system is then assessed bottom-up using test data from subtasks, and the scenario where confidence limits are dependent is also discussed. Numerical examples demonstrate that the BBA method can effectively handle zero-failure data compared with traditional methods, and the reliability of LSB construction is verified to reach 0.9544 with a confidence degree of 0.9.