Research On Vibration Similarity Of Hoop Truss Antenna Based On Similarity Theory

Satellite spaceborne antenna is an important part of the satellite system which is an important work platform to ensure satellite data transmission and information communication and obtains high-resolution images. Spaceborne antenna is under load by itself and others for a long time in the process of work. The load will damage to spaceborne antenna directly or indirectly which will eventually result in that the satellite can’t continue to work normally. However, Spaceborne antenna’s size is so large that the ground test can’t carry out normally which is limited by some factors such as site and testing equipment. Based on the above analysis, it is very essential to test by scaling model and predict vibration characteristic of the prototype.Based on similarity theory in this paper, hoop truss antenna in simple which is narrowed by scale is analyzed by dimensional analysis method and the one which isn’t narrowed by scale is analyzed by segmentation similarity method. Through analysis, the modal and response of the prototype can be predicted.Structural dynamic similarity criterion of the scaled model of hoop truss antenna in simple is established which is suitable for the rule of gravity by dimensional analysis method, as well as the one which ignores the rule of gravity. Using dummy mass method, structural dynamics similarity relation is evolved which meets both of the requirements of material properties and the rule of gravity. It is verified that hoop truss antenna model which is scale-narrowed can imitated the modal and response of the prototype correctly through finite element method.The empirical formula between fundamental frequency and other physical parameters of hoop truss antenna is established through the empirical formula method of the similarity theory, and certifies the feasibility of formulas. Comparing with the structure which is narrowed not by scaled, the response of the prototype is predicted by segmentation similarity method. At the same time, it is verified that the modal and response of the prototype of hoop truss antenna model can be predicted correctly by adopting similarity theory through tests.Analyze the modal of the scaled model of hoop truss antenna through test, and compare with the result of test and that of finite element simulation. The correctness of finite element model is verified. In addition, it is also verified the feasibility of segmentation similarity method to predict vibration characteristic of the prototype.