Dynamic Characteristic Prediction of Large Satellite Antennas by Component Tests

摘要

The purpose of this study is to predict accurate frequencies of large space structures from component modal test results. We deal with structures such as large satellite antennas, on which it is difficult to perform modal tests on the whole structure. A method, considering the effect of untested components as boundary mass and stiffness, is proposed for obtaining accurate frequencies of a structure. Boundary mass and stiffness are found by reducing mass and stiffness matrices of untested components to boundary degrees of freedom. A tested component with these reduced matrices at the boundary gives accurate frequencies of the whole structures analytically. In performing modal tests, it is important to simulate these matrices as boundary mass and stiffness. A procedure to find boundary mass and stiffness is shown, and a numerical example is given to show that the proposed method is effective for predicting accurate frequencies of whole structures.