Structural uncertainty estimation through a Craig-Bampton Stochastic Method optimisation in satellites structures

Abstract The Craig-Bampton method in micro-vibration analysis is a widely applied tool to reduce computational effort when dealing with complex assemblies. However, structural uncertainties tend to arise and undermine the reliability of deterministic tools such as finite element method. Hence, the aim of this paper is to investigate a stochastic version of the classic Craig-Bampton approach by estimating perturbation parameters directly linked to structural uncertainties. It is shown that the proposed approach can be ultimately configured as an optimisation black box tool to update the finite element model by improving the model correlation with test data. In addition it provides useful insight on the distribution of perturbation parameters to account for structural uncertainties in the analysis. Applications to real satellite platforms are shown to validate the approach with different optimisation functions based on the modal dynamics requirements.