Three-dimensional large deformation reconstruction for slender wing-like structures from strain measurements

Shape-sensing technology has significant applications in real-time monitoring and controlling flexible aerospace structures. Aiming at large deformation of flexible wing-like structures, an algorithm that incorporates geometric nonlinearity is developed for three-dimensional shape reconstruction based on strain measurements. The full-field three-dimensional deformation is described in terms of the deflection of the spatial reference line and the motions of the cross-sectional plane. A certain number of strain measurements distributed on the structural surface are used to estimate the generalized strains and the warping deformation, which can further determine the position of an arbitrary material point in the structure by a series of recursion relations. Instead of the experimental research, the desired strains and the deformation as references are simulated by high-fidelity finite element models. A simple tube model and a more realistic composite wing model are investigated separately to demonstrate the present method in reconstructing deformed shapes under various applied loads. Besides, the modal method was also used to calculate the deformation as a comparison. The result has demonstrated the high accuracy and capability of the present method in three-dimensional shape reconstruction, especially for large deformation problems. The warping effect is demonstrated to have a significant impact on predicting the twist angle. More attention should be paid to accurately describing the warping deformation of complicated wing models, especially when the bending deformation is large.