On-board preventive maintenance: analysis of effectiveness and optimal duty period

To maximize the reliability of a spacecraft which performs a long-life (over 10-year) deep-space mission (to an outer planet), a fault-tolerant environment incorporating on-board preventive maintenance is highly desirable. In this paper, we present an initial model-based study which identifies the key factors for the reliability gained from on-board preventive maintenance and demonstrates the capability of analytic modeling in determining the optimal interval between maintenance (duty period).