Feasibility Assessment of Deployable Composite Telescope

Abstract

Volume constraints in existing launch vehicles require large space-based sensors to be folded during launch and subsequently deployed in space. This paper outlines the development of a prototype deployable astronomical telescope that would maintain both structural stability and optical alignment for potential space-based deployment. To achieve this goal, the structure must possess adequate stiffness and maintain its positional accuracy after a deployment cycle has ensued. The development and testing were based on a consumer-astronomy Newtonian telescope. A foldable carbon-epoxy composite replacement structure was integrated to replace the aluminum-truss assembly provided by the manufacturer. The composite telescope’s structure and optical output were evaluated using computational (finite-element analyses and closed-form equations) and experimental methods. The structure was subjected to postdeployment displacement tests to quantify alignment accuracy. The stresses introduced in folding the tape springs were evaluated for both magnitude and mode of failure using the Tsai-Wu failure criterion.