Design and Sizing Method for Deployable Space Antennas

Abstract

The dimensions of space borne instrument-, antenna- and solar array structures do often exceed the available envelope of common launch vehicles. To realize such systems anyhow the structures are provided with folding mechanisms that allow a space saving orbit transfer. A side effect from this deployment concept is the fact that a structure which provides a sufficient deployed stiffness for space environment can also fulfil the stiffness requirements for launcher payload in stowed configuration. Consequently, the sizing of such structures demands the consideration of different configurations that are composed out of the same essential structural parts. The thesis, thereby, illustrates how the roles of the single components change for the different configurations. For instance, a component that carries a major part of the load in a first configuration can be nearly offloaded in a second one. Moreover, this component can load another part with its own mass, whereas, this other component is passive in the first configuration and needs to be carried. Thus, the core of this thesis contains the introduction into an exemplary antenna structure design as well as a method for an adequate sizing of all relevant structural parts. The developed method is then integrated in a Finite Element Analysis (FEA) aided, closed loop sizing chain. The used automated close loop sizing helps to rapidly react on changed requirements and generates the possibility of performing fast parameter studies to improve the understanding of such a sophisticated structure. The validity of these approaches is finally proven by presenting a re-sized antenna configuration after the parameter study and its evaluation. This final configuration more than meets the previously defined requirements for the exemplary antenna structure.