Deformation and Load Detection of Wing Structure Based on Load-Strain Linear Superposition

The wing is a crucial functional component of an aerospace vehicle, and its service loads and deformations are key information for evaluating the functional state of the structure. It is almost impossible to obtain accurate wing structural deformation and homogenized load information by direct measurement methods due to constraints inherent in the flight environment and limited sensor installation space. Employing load identification and deformation reconstruction techniques based on strain information is the most viable approach. Nevertheless, prevalent methods, such as the inverse finite element method, Ko displacement theory, and modal superposition method, can only reconstruct deformations and are insufficient for determining distributed loads. In this article, fiber Bragg grating (FBG) sensors are used to obtain the strain information of the wing structure. This study adopts the load-linear superposition method to overcome the constraints of conventional techniques, which excel in reconstructing deformation but cannot accurately identify the load applied to the wing, especially the magnitude of the distributed load. By establishing a finite element model, simulation experiments are carried out for two working conditions: double and full-field load. After that, the experiment is carried out for three working conditions: single, double, and full-field load. The results show that the reconstructed displacements (RDs)/loads are consistent with the measured displacements (MDs)/loads under various operating conditions. The method proposed in this article realizes the deformation reconstruction and load identification of the wing structure. It provides new ideas for the service state monitoring of complex structures.