Shape Sensing of a Complex Aeronautical Structure with Inverse Finite Element Method

Abstract

The inverse Finite Element Method (iFEM) is receiving more attention for shape sensing due to its independence from the material properties and the external load. However, a proper definition of the model geometry with its boundary conditions is required, together with the acquisition of the structure’s strain field with optimized sensor networks. The iFEM model definition is not trivial in the case of complex structures, in particular, if sensors are not applied on the whole structure allowing just a partial definition of the input strain field. To overcome this issue, this research proposes a simplified iFEM model in which the geometrical complexity is reduced and boundary conditions are tuned with the superimposition of the effects to behave as the real structure. The procedure is assessed for a complex aeronautical structure, where the reference displacement field is first computed in a numerical framework with input strains coming from a direct finite element analysis, confirming the effectiveness of the iFEM based on a simplified geometry. Finally, the model is fed with experimentally acquired strain measurements and the performance of the method is assessed in presence of a high level of uncertainty.

Coupling of peridynamics and inverse finite element method for shape sensing and crack propagation monitoring of plate structures

“…The underlying idea on derivations of Eqs. (40)(41)(42)(43) is that energies required to break all associated bonds crossing unit crack between particles within the same ply or two adjacent plies of a laminate are the same with related critical energy release rate. It is also important to note that the bonds are assumed to fail only in tension because of the predominant mechanism of the delamination/fiber/matrix failure modes of a laminate.…”

“…The most attractive ones including iMIN3 [32], iQS4 [33], and iCS8 [34] inverse-shell elements employ C 0 -continuous interpolation functions in accordance with the firstorder shear deformation theory (FSDT). Particularly, the iQS4 element has recently gained a popularity for shape sensing applications on simple/complex geometries, e.g., ship and offshore structures [35][36][37][38][39] and stiffened aerospace panels [40][41], due to its merits for practical modelling of large-scale structures with low-cost sensor measurement and highly accurate displacement estimations [42][43]. Several studies have shown the superior applications of iFEM/iQS4 approach Coupling of peridynamics and inverse finite element method for shape sensing and crack propagation monitoring of plate structures for damage identification in monolithic/stiffened structures having isotropic/orthotropic material properties [44][45][46][47][48][49].…”

Variable Thickness Strain Pre-Extrapolation for the Inverse Finite Element Method

“…The iFEM has been successfully applied to the monitoring of a container ship [ 19 , 20 ], wind turbines [ 21 , 22 ], and to complex aeronautical structures [ 23 ]. Colombo et al in [ 24 ] developed an iFEM-based damage detection methodology, and current research is expanding towards damage identification and quantification [ 25 , 26 , 27 , 28 ]; very recent developments are in the direction of a non-deterministic displacement reconstruction [ 29 ].…”

Experimental Shape Sensing and Load Identification on a Stiffened Panel: A Comparative Study

“…Quadrilateral inverse shell elements have been developed and applied using standard [ 33 , 34 , 35 ] and isogeometric [ 36 ] formulations. Recently, the iFEM has been experimentally applied to the full displacement field reconstruction of an aeronautical stiffened panel in [ 37 ].…”