Dynamic Analysis of Modular Space Deployable Antenna Structure with Multi Fold Rib

Aiming at the urgent need for the development of large-diameter space deployable antennas, a new configuration of support structure for the multi fold rib modular space deployable antenna is proposed. The antenna support structure consists of seven multi fold rib modules, each module mainly includes members such as upper chord, lower chord, inclined chord, center bar, vertical bar, two-fold center bar and tension cable. Based on the proposed structural scheme, a single-module principle prototype was developed, and a functional test was carried out. According to the actual geometric parameters of the multi fold rib antenna support structure, the spatial coordinates of each key point are calculated, and the 7-module finite element model of the antenna support structure is established by using ANSYS finite element software. The modal analysis of the space deployable antenna structure is carried out by using the subspace method, and the modal constraints of the structure in the stable working state of the orbit are considered. In order to better understand the on-orbit vibration characteristics of the antenna structure, the variation law and mode shape characteristics of the antenna's natural frequency are analyzed, and the influencing factors of the support structure's natural frequency are also analyzed. The research results show that the design scheme and principle of the multi fold rib modular space deployable antenna support structure is feasible. The antenna support structure has the characteristics of low frequency, dense frequency and large flexibility. It exhibits overall vibration in low-order modes and local vibration in high-order modes. By appropriately increasing the diameters of the upper and lower chords and inclined chords, the first-order natural frequency of the support structure can be increased and the structural rigidity can be increased. The research results provide theoretical basis and technical support for the basic research of space deployable antennas and future engineering applications.