PENG Qi’an, WANG Sanmin, ZHI Changjian, LI Bo
JOURNAL OF VIBRATION AND SHOCK. 2018, 37(9): 56-60.
With increase in array elements, the computation amount to analyze an array deployable structure is huge based on the conventional FEM dynamic analysis method, even the computation becomes impossible. The specification dynamic method (SDM) for a planar linear array deployable structure with scissor-like elements was proposed according to its feature of it being regularly composed of element mechanisms. The superposition node DOFs among element mechanisms and internal node DOFs were separated with this method to realize element characteristic matrices added end to end circularly, and obtain the global stiffness matrix and mass one of an array deployable structure. Taking a 55 planar linear array deployable structure with scissor-like elements as an example, its natural frequencies and dynamic responses were analyzed with the SDM. The results showed that the structure’s natural frequency decreases to 0 Hz rapidly when its deployable angle is close to 0 or 180; when external loads are applied, the dynamic responses of the system are periodic vibration, periodic vibration with the maximum amplitude attenuated, and no vibration, respectively under undamped, underdamped and overdamped conditions; the structure with the deployable angle close to 0 or 180 is unstable, the safe range of the deployable angle should be 20 to 160; in addition, appropriately increasing damping can reduce the structure’s vibration effectively; the SDM can be used to improve modeling efficiency, and it is easy to be regularly programmed for computation.