Construction and identification of a prior stochastic model for an uncertain rigid body

International audience; This research is devoted to the construction and the identification of a prior stochastic model for an uncertain Rigid Body (RB) of a multibody dynamical system (MDS). The methods developed in the context of the multibody dynamics analysis are commonly used in many application fields (Automotive, railway vehicles, launch vehicle,) for which the required accuracy makes the modelling and the quantification of uncertainties unavoidable whenever they are not negligible. In some particular cases, rigid bodies can not be considered as deterministic (RB model of passengers, of a fuel tank,). In this context, we propose a construction of a random RB using the maximum entropy principle. Therefore the mass, the center of mass and the tensor of inertia of the classical deterministic rigid body are replaced by random variables which allows the random dynamical response of the MDS to be calculated. The PDF of these random variables depend on some parameters which are identified using experimental responses of the MDS. The methodology is presented and is validated through an application.