基于FBG的飞机起落架载荷测试技术研究

针对某型飞机起落架三向载荷的监测需求,提出了一种采用光纤光栅(Fiber Bragg Grating,FBG)传感和多元线性回归相结合的起落架载荷测试方法。通过对起落架进行有限元仿真分析,得到了不同载荷作用下起落架的应变分布,根据应变分布特征确定FBG应变传感器的布片位置,形成应变传感网络。在此基础上,进行了主起落架地面静态载荷标定试验,并通过多元线性回归的方法形成应变-载荷计算方程组,最后对载荷计算方程组进行了验证性试验。研究结果表明,基于FBG的起落架载荷测试方法能有效反算起落架的三向载荷,反算得到的载荷与施加载荷的相对误差在5%以内,满足实际工程应用需求。

Research on Load Testing Technology of Aircraft Landing Gear Based on FBG

In order to meet the monitoring requirements of three-way load of a certain aircraft landing gear, a landing gear load test method was proposed based on fiber Bragg grating (FBG) sensing and multiple linear regression. The strain distribution of the landing gear under different loads was obtained with finite element analysis software. According to the characteristics of strain distribution, the position of the FBG strain sensor was determined, and the strain sensing network was formed. On this basis, the ground static load calibration experiment of the main landing gear was carried out, and the strain-load calculation equations were formed by multiple linear regression method. Finally, the load calculation equations were verified by experiments. The research results show that the method based on fiber Bragg grating can effectively back-calculate the three-way load of landing gear, and the relative error between the back-calculated load and the applied load is within 5%, which meets the actual engineering requirements.