Base force and moment based finite element model correlation method

The accuracy of the finite element model is an important aspect, especially in the aerospace domain, where design margins are barely minimum. Hence, standard test-analysis model correlation methods apply to assess the quality of the analytical model. However, it is observed that these standard correlation techniques are inadequate to assure the model capability to predict the forced response characteristics of complex structures. The base force assurance criterion is found to be a good tool to overcome this inadequacy. During the dynamic test of the structure, the force measurement device can be used to measure the transmitted force to the base. Thus measured base forces, and the moments computed from the measured forces are vector correlated with the analytical force and moments to predict qualitatively the analytical model capability to represent the design critical peak acceleration responses and the global modes. The procedure is demonstrated using a set of experiments conducted on a real spacecraft under the sine excitations in two mutually perpendicular directions. The sensitivity of the base force assurance criterion to the inaccuracies that may be present in the finite element model and/or in the experimental results is evaluated using simplified Monte Carlo simulations. (C) 2021 COSPAR. Published by Elsevier B.V. All rights reserved.