FBG 传感技术在飞机机翼动态形变监测中的应用

机翼是飞机的关键部件之一,在飞行过程中对机翼形变进行在线监测,有助于提升飞机的安全性能及任务执行能力。 为此,本文提出一种基于光纤布拉格光栅传感技术的机翼动态形变测量系统;理论分析了 FBG 波长变化量与机翼表面曲率变 化的关系,利用 FBG 温度传感器实现应变补偿,利用三次样条插值实现离散曲率的连续化,采用基于连续曲率的形变重构算法 实现机翼形变测量;在 CA42 飞机的 4 个翼面上布置了 36 个 FBG 应变传感器,4 个 FBG 温度传感器,通过地面静力试验得到了 机翼的形变测量误差为 2. 5% ;最后,针对机翼动态形变测量系统开展了飞行试验,试验过程完整地记录下了机翼表面的应变、 温度及形变信息。 试验结果表明,由机翼形变产生的翼梢位移量正比于机翼法向过载,系数分别为 86. 33 mm/ g(左机翼)及 80. 04 mm/ g(右机翼),翼梢最大位移量 250 mm,发生在法向过载为 2. 25 g 的时刻。 此外,飞机机动半径越小,机翼形变量越 大。 机翼动态形变测量系统体现了良好的工程适应性。

Application of FBG sensing technology in dynamic deformation monitoring of aircraft wings

Wing is one of the key components of aircraft. On-line monitoring of wing deformation during flight is helpful to improve the safety and mission performance of the aircraft. Therefore, a dynamic wing deformation monitoring system based on the fiber Bragg grating sensor technology is proposed in this article. The relationship between wavelength variation of FBG and wing surface curvature is analyzed theoretically. The strain compensation is realized by the temperature sensor, and the serialization of discrete curvature is realized by cubic spline interpolation. Then, the deformation reconstruction algorithm based on continuous curvature is used to measure the wing deformation. 36 FBG strain sensors and 4 FBG temperature sensors are set on the wing surfaces of the CA42 aircraft. The ground static test results indicate that the measuring error of wing-tip deflection is 2. 5% . Finally, a flight test is carried out for the wing dynamic deformation measurement system. The strain, temperature and deformation data of the wing surface are recorded completely during the test process. The flight test results show that the wing tip deflection caused by the wing deformation is directly proportional to the vertical acceleration of the wing, and the coefficients are 86. 33 mm/ g (left wing) and 80. 04 mm/ g (right wing), respectively. The maximum deflection of the wing tip is 250 mm, which occurs when the normal overload is 2. 25 g. In addition, the smaller the radius of the aircraft maneuvering, the more the wing deforms. The dynamic wing deformation monitoring system shows good engineering adaptability.