Research on dynamic deformation measurement of wings based on FBG distributed sensing

Abstract

In flight test, the aircraft needs to fly under heavy overload, resulting in the aircraft to withstand large dynamic structural loads, such as large bending moment at the root of the wing, deformation of the wing, which is prone to fatigue damage. So it is necessary to measure the elastic deformation of the wing real-timely with high precision. At present, photogrammetry is mainly used for wing deformation measurement in China. However, the installation position of photogrammetry is limited, and it is difficult to implement it. According to the requirement of aircraft dynamic structural deformation measurement, the FBG distributed sensing technology is studied in depth, and the mathematical model of the relationship between FBG grating wavelength data and wing deformation is constructed. The wing deformation model coefficients are calibrated by high-precision calibration technology combined with multi-measuring equipment, and the deformation curve is fitted by B-spline curve interpolation. Dynamic deformation measurement method for wing structure based on FBG distribution is constructed. The measurement method is feasible and the result meets the requirement of measurement precision.