基于结构分区与应变电桥解耦的支柱式主起落架载荷测量

为解决应变法测量支柱式主起落架载荷中的低灵敏度、高耦合度和强非线性等问题，提出了结构分区解耦和应变电桥解耦设计方法。在集中传力的轮轴和活塞杆上优选出不同等效分量载荷作用下的结构变形有效部位，并在对应部位优化布置了弯矩-剪力-扭矩应变电桥阵列，通过某型飞机起落架综合加载校准，得到了简洁可靠的支柱式主起落架载荷测量模型。载荷校准试验表明:轮轴上剪力电桥对垂向载荷的响应灵敏度相比支柱上拉压电桥对垂向载荷的响应灵敏度提高约60%，并与压缩行程变化无关。在该型机着陆试验中，利用所提载荷测量模型和飞行数据计算得到了满足工程精度要求的主起落架着陆载荷和缓冲器功量吸收结果。 

Load measurement based on structure partition and strain bridge decoupling for telescopic main landing gear

In order to resolve the problems of low sensitivity, high coupling degree and prominent nonlinearity during the load measurement of telescopic landing gear by strain method, the decoupling design methods of structure partition and strain bridge are proposed. Trough optimization design the effective parts of structure deformation under different equivalent load components were selected on the wheel-axis and piston rod with concentrated force transfer, and the bending moument-shear-torque strain bridge array was installed in the corresponding position.Furthermore, a simple and reliable load measurement model was obtained by combined loading calibration of landing gear.The load calibration tests show that the response sensitivity of the shear bridge on the wheel-axis to the vertical load is about 60% higher than that of the tension-compression bridge on the strut, and has no relation with the change of the compression stroke.Finally in the landing tests the load measurement model and flight data were used to calculate the landing load and buffer power absorption results which satisfy the requirments of engineering accuracy.