Parametric Optimization of Joints and Links of Space Deployable Antenna Truss Structure

Abstract

With the volcanic proliferation in high bandwidth communication, space-borne antennas are required to have Large Diameter Reflectors (LDR) of size 6 m or more which will cater to the requirements of high bandwidth data transmission. Space deployable antenna structures are a buzzword today which are required to occupy compact volume during launching due to space crunch in, state-of-the-art, contemporary launch vehicles. These compact geometric topologies are later deployable to the full configuration after orbit insertion. The antenna deployable mechanism consists of a truss ring structure and a flexible reflective metallic mesh supported by a net. Hinges play a vital role in folding the antenna truss to compact the volume and for the smooth deployment of a ring truss structure to its full configuration. Therefore, an optimization investigation is carried out in designing the parameters of hinge joints of AstroMesh (Thomson, M.W.: The astromesh deployable reflector. IEEE Antenna Prop. Soc. 1516–1519, 1999.) configuration. Critical parameters of joints and links are considered as design variables, and circumstances of the system are described by design constraints. An objective function is formulated on the basis of the compact volume of stowed configuration. Variation of link parameters is plotted with the size of stowed configuration. The results are also extrapolated for a 12 m diameter truss structure and compared for optimum design parameters. A volumetric efficiency of 99.7% is achieved for a 12 m diameter truss which is optimum and plotted with variation in the number of bays. This optimized deployable antenna design has the potential for launch in futuristic Indian space missions.