Dynamic Characterization And Parameter Analysis For Space Inflatable Structure

Inflatable space structure has some notable advantages such as starting light weight, small folding size etc. In the large space structures, such as large space antenna, solar Panels, and other fields, the structure has broad application prospects. At present, the inflatable space structure research focus on the inflatable antenna and it's a major application direction.This thesis describes the research progress on inflated space structures and its application and development abroad in detail, discusses the relative theories, and introduces the geometric formulas of stress stiffness effect, the formulas which are used to calculate the frequency in the modal analysis. It takes the theoretical analysis on the characteristics of the inflated structure under static load. To support the inflated beam model for the study, theoretically studied the relationship of the inflated beam axial compressive stiffness and global bending stiffness between the structure internal pressure. And, on the basis of the study findings, the nature vibration frequency solution formula of the inflated beam with concentrated mass has been deduced. The analytical solution of the beam baseband modal frequency has been obtained. Then, the inflatable antenna components Finite Element Analysis have been taken in order. Obtain the numerical solution of the inflated cantilever beam axial compress stiffness, global bending stiffness and the base free vibration frequency. And compared with the analytic solution, the reliability of numerical method has been verified. And then take the numerical analysis on the features under static internal pressure and the modal analysis with the different inner pressure conditions of the inflated beam, the inflatable 18-sides toroidal ring and the inflatable antenna support system before and after the structure rigidizition. The film unit and shell element were employed to simulating the inflatable structure before and after the structure rigidizition. Then, compare the numerical results to identify the optimal structuraldesign programs.The results of theory and numerical analysis showed that: the inner pressure does not affect the structure overall stiffness of Inflatable tubes and rings; and the internal pressure influences the local structure modes' frequencies; but it doesn't effect the structure global modes' frequencies; so it can not increase the vibration frequencies of the inflated structure global modes. The simulation results of the global vibration frequencies of the inflated structure are almost same when using the membrane element and shell element, with only slight difference in local modes and frequencies.