A stochastic model updating technique for complex aerospace structures

Abstract

The accurate prediction of the structural response of spacecraft systems during launch and ascent phase is a crucial aspect in design and verification stages which requires accurate numerical models. The enhancement of numerical models based on experimental data is denoted by model updating and focuses on the improvement of the correlation between finite element (FE) model and test structure. In aerospace industry the judgment of the agreement between model and real structure involves the comparison of the modal properties of the structure. Model updating techniques have to handle several difficulties, like incomplete experimental data, measurement errors, non-unique solutions and modeling uncertainties. To cope with the computational challenges associated with the large-scale FE-models involving up to over one million degrees of freedom (DOFs), enhanced strategies involving model reduction and parallelization are required. Two numerical examples, namely an antenna reflector and a full-scale satellite model, will be used for demonstrating the applicability of the employed updating procedure to complex aerospace structures.