国产欧美精品一区二区,中文字幕专区在线亚洲,国产精品美女网站在线观看,艾秋果冻传媒2021精品,在线免费一区二区,久久久久久青草大香综合精品,日韩美aaa特级毛片,欧美成人精品午夜免费影视

A full field non-contact strain measurement system is established to experimentally study the deformation and vibration characteristics of variable section rudder surface structure under random excitation load. Taking the variable section rudder surface structure made of 2A12 aluminum alloy as the test object, a high-resolution digital camera is used to record the clear speckle image of the structure in the whole field, and then the continuous deformation of the structure surface is directly measured by three-dimensional digital image correlation method(DIC). At the same time, the vibration characteristics of the collected speckle image are analyzed by Fourier transform, The modal frequencies and modal shapes of the variable section rudder surface structure are obtained. In order to verify the accuracy of the vibration characteristic results obtained by non-contact measurement, it is compared with the vibration response signal obtained by using a small mass normal temperature acceleration sensor. The test results show that in the test frequency band of 0~500Hz, the first three-order modal parameters of variable section rudder surface structure identified by three-dimensional digital image correlation method are very consistent with the measurement results of acceleration sensor. The error of the first three-order natural frequency is less than 2%, the error of damping ratio is less than 6%, the first two-order modal modes are bending mode, and the third-order modal mode is bending torsional coupling mode, The effectiveness of the full field vibration measurement technology based on three-dimensional digital image correlation is verified, which provides a basis for the non-contact vibration measurement of nonlinear variable section rudder surface structure in high temperature environment.