Reliability analysis of spacecraft structures under static and dynamic loading

The aim of the present paper is to demonstrate that, thanks to recently proposed simulation-based methods, it is now possible to efficiently analyse the reliability of large-scale structures modelled with very large FE systems. This capability is of paramount importance for industrial applications, because the related FE models steadily grow in size and so does the number of model parameters associated with uncertainty. The analysis methods applied in this study belong to the class of advanced Monte-Carlo simulation methods, with which the computational costs induced by direct simulation can be drastically reduced. Based on the theoretical foundations of the methods, which are specifically geared towards problems featuring thousands of parameters affected by uncertainty, the present paper provides the first demonstration that these methods can be used to assess the reliability of complex structural assemblies, even for extremely high levels of reliability. The reliability analysis is performed using a refined finite element model (120,000 DOF) of a satellite, both under static and dynamic loading. For the static load case the reliability can be estimated with great efficiency, whereas for the dynamic load case the performance depends on the considered frequency range. The obtained results are very significant in that they show the feasibility of a full scale analysis of the structural reliability in a design context for large-scale structures.