A FE model updating model for the simulation of the assembly process of large and lightweight aeronautical structures

Abstract

In the context of thea assembly of large aeronautical structures, the flexibility of the parts often leads to the nonconformity of the assembly or, at least, requires additional time-consuming operations. In order to deal with this problem, one must take this flexibility in to account during the tolerancing process. Investigations of a non-rigid body tolerancing process have shown that a robust model is necessary in order to achieve satisfactory predictability. It was also found that the finite element model used, based on a simplified geometry, was not accurate enough. The approach proposed in this paper to obtain an accurate tolerancing process consists in updating the stiffness and mass properties of the FE model based on measurements taken on the assembly line during the assembly process.The objective is to take these measurements using only tools which are available on the chain (such as manipulation or control tools). This implies that only static strength and displacement information can be used. This is achieved through a clever measurement methodology and a model updating method based on the constitutive relation error