Abstract:  Large-scale deformation monitoring of allomorphic aircrafts in the flight processes was a research difficulty and hot spot in the aerospace field， and the existing methods were difficult to achieve high-precision three-dimensional deformation monitoring during the flight of the aircrafts. Aiming at this problem， a flexible skin-shaped fiber reconstruction method for a variant aircraft was proposed based on optical fiber sensing to achieve deformation monitoring during flight of the aircrafts. Based on the principle of fiber grating strain sensing， the relationship between fiber strain and curvature was derived， the conversion matrix between the local coordinate system and the global coordinate system of optical fiber sensing was established， the conversion of fiber measurement point coordinates to the global coordinate system was realized， and the three-dimensional deformation reconstruction algorithm was studied based on curve fitting according to the spatial curve fitting method. At the same time， in order to reduce the measurement errors of the fiber optic sensors， the calibration tests of the fiber optic sensors were carried out to obtain the strain sensitivity of the sensors. In order to verify the effectiveness of the proposed method， the three-dimensional deformation reconstruction of flexible skin samples under different curvatures was tested experimentally. Experimental results show that the average error of the shape reconstruction method is as 3.5% and the minimum error is less than 2.1% in the deformation ranges of 0～15.38 m-1 curvature of flexible skin samples. The proposed method has a good application prospect in aerospace and other fields. 

Key words:  , multicore fiber grating, three-dimensional deformation, flexible skin, aircraft, refactoring algorithm

摘要： 变构型飞行器在飞行过程的大尺度变形监测是航空航天领域的研究难点和热点，现有方法难以实现飞行器飞行过程中的高精度三维变形监测。针对这一问题，提出一种基于光纤传感的变构型飞行器柔性蒙皮形状光纤重构方法，以实现飞行器飞行过程中的变形监测。基于光纤光栅应变传感原理，推导了光纤应变和曲率之间的关系，建立了光纤传感局部坐标系和全局坐标系之间的转换矩阵，实现了光纤测点坐标到全局坐标系的转换，根据空间曲线拟合方法研究了基于曲线拟合的三维变形重构算法。同时，为了减小光纤传感器的测量误差，对光纤传感器进行标定测试，获得了传感器的应变灵敏度。为了验证所提方法的有效性，对柔性蒙皮样件在不同曲率下的三维变形重构进行了实验测试。实验结果表明，柔性蒙皮样件在0～15.38 m-1曲率的变形范围内，形状重构方法的平均误差为3.5%，最小误差不足2.1%。所提方法在航空航天等领域具有较好的应用前景。

关键词: 多芯光纤光栅, 三维变形, 柔性蒙皮, 飞行器, 重构算法