Global Sensitivity Analysis for Modeling the Free-Flight Behavior of an Artillery Projectile

Abstract

A vehicle’s in-flight behavior can be represented by the Newton–Euler equations of motion: usually, such a model has a nonlinear and continuous description based on ordinary differential equations. The model structure can be altered using analytic transformations (such as transformation into a quasi-LPV structure) and, when the model is supposed to reflect an existing physical system, some of its parameters might be uncertain. This paper’s objective is twofold: first, to investigate if a quasi-LPV model does accurately replicate the physical behavior of a large-caliber spin-stabilized projectile in free flight; second, to verify if the available embedded sensors data could be used to determine nonidentifiability of uncertain model parameters. To investigate these prospects, a permutation-based global sensitivity analysis is employed. The proposed study has highlighted the nonidentifiable parameters of the model, during either the whole flight or some periods of it. These results can help to enhance the preparation of free-flight experiments at the open-range test site of the French-German Research Institute of Saint Louis.