Optimal Cable-Stayed Forms for Pretensioned Space Structures

To improve the deployed stiffness and mass efficiency of pretensioned spacecraft structures, the efficacy of cable-stayed configurations is analyzed in this paper. The reference structure is a deployable array wing that supports a series of radio frequency panels for space-based antenna applications, and it is designed to be z-folded under stowage. Due to the significant mass of the panels and the large span of the array wing, the entire structure is susceptible to low-frequency excitation. Lightweight pretensioned cables that elastically support and stiffen the array along its span are found to drastically raise its fundamental frequency and critical buckling load. An analytical model that is validated by finite element simulations is used to predict the vibration and buckling modes of the constituent structures for both the reference and cable-stayed architectures. A parametric analysis then optimizes the cross section of the load-bearing members, cable attachment points, and the number of cables to maximize the fundamental frequency for the structural systems. These optimal cable-stayed forms are compared against the reference design, and their effectiveness is demonstrated with a 157% and 255% increase in fundamental frequency for one and two cables, respectively.