The impact force identification of composite stiffened panels under material uncertainty

This paper presents a synthesis approach to address the problem of uncertainty in the impact force identification. The effects of material uncertainty on dynamic responses of the structure are studied by using Monte Carlo simulation. Six parameters, including mechanical properties and thermal coefficients, are considered as independent random variables. A parametric study is conducted to select four parameters as the optimization variables in the following step of model updating. The technique of model updating is used to correct the modeling errors caused by material uncertainty. Then, an improved inverse analysis technique based on the finite element method and mode superposition method is taken for impact force identification. In this study, the present method is performed on a composite stiffened panel, and the effect of noise on the performance of identification is also discussed. The results of the study show that the developed approach is capable of identifying the impact location and reconstructing the force history accurately by reducing material uncertainty through the modal updating procedure.