单边固支板结构弯矩光纤光栅监测方法

Bending Moment Monitoring Method of Unilateral Clamped Plate Structure Based on Optical Fiber Grating

在飞行过程中,机翼结构会受到不同外力作用而产生变形。作为内力矩的一种,弯矩大小与结构受力和变形量有关。因此,针对变形状态下的弯矩测量对于飞行器状态监测具有重要意义。该文以等宽、等厚、等截面的单边固支板结构作为机翼的简化模型,提出一种基于光纤光栅传感器的结构弯矩测量方法,推导得到板结构在弯曲变形情况下的应变-弯矩转换方程。通过构建单边固支板结构光纤监测系统,实现对不同载荷下板结构关键位置的弯矩测量,单点加载、多点加载与均布加载方式下均方根误差分别约为0.883、0.825、0.689。

During the flight,the wing structure will deform subjected to different external forces.Bending moment,as a kind of internal moment,has a close relationship with the force acting on the structure and the deformation size of the structure.Therefore,it is important to measure the bending moment for the aircraft condition monitoring under the deformation condition.In this paper,a bending moment measurement method based on fiber Bragg grating sensor was proposed by using the cantilever plate structure with an equivalent-width,thickness and uniform cross section as a simplified model of wing structure.The strain-bending moment transformation equation under the bending deformation condition was deduced.By building a bending moment monitoring system of unilateral clamped plate structure,the bending moment measurement of key positions on the plate structure under different loads was realized.The root mean square error values of the single-point load case,multi-points load case and uniform load case are 0.883,0.825,0.689 respectively.