Coil Buckling Mechanism And Structural Dynamical Analysis For Coilable Extendable/Retractable Space Masts

Space mast is widely used deployable space structure, which makes up of the basic structural component of large aerospace structure, and the related research and development is the most active field in deployable space structures. The basic research and rather application began in later of 1960s in oversea advanced nations. But in China, the theoretic and technology researches involved with space mast just began in the early of 1990s without any practical aerospace applications.Coilable mast is a basic type of extendible/retractable space truss masts, and it’s been widely studied and applied in spaceflight since it has the advantages of simple constitution, high stiffness, high reliability and high coil ratio.The study of the whole process of the extending and coiling of the extendable space mast has always been difficult as large displacement occurs and the dynamic performance is very complex. Meanwhile, the critical buckling force of the space mast is the precondition of the coiling, and it greatly influences the structural performance, driving efficiency, design of the driving machine and the choice of the electrical power.At first, the detail design, geometry and topology, deployment mechanism and structural mechanical performances are introduced for a hinged and hingeless coilable space mast, respectively. Based on the elastic stability theory and Castigliano energy principle, the critical buckling forces are formulated respectively in detail for the local coil mode and overall helix mode, and the parametric analysis is performed. And a comparison between the analytical formula and FEM method is also made to show the rationality of the computational model.Besides, the structural dynamical performance is performed comprehensively for the space masts at fully deployed configuration. The effects of the cables’tension on the vibration performance as modal shape and frequency are evaluated. Also the transient responses subjected to the impulse force are simulated with varied examples. The analytical theory and research works can make contributions to the design of coilable space mast.