The mechanical properties of high-stiffness deployable sunshield structure based on thin-walled composite materials

This paper presents the design of a self-deployable sunshield structure made from thin-walled composite materials. The sun shield is designed to effectively suppress stray light and provide thermal protection for space cameras, making it ideal for scenarios where launch vehicle space is limited. The study details the functional mechanism, structural components, and mechanical properties of the sun shield using finite element analysis. The deployment mechanism utilizes parallel tape springs made from composite materials as the driving force. Once fully deployed, the structure exhibits excellent dynamic stiffness characteristics. This paper examines the relationship between the torque and the folding angle ( θ ) of the tape springs during the deployment process. Simulations were conducted to analyze the modal characteristics of the sunshield in both its folded and deployed states, with the first-order modal frequency after deployment measured at 31.8 Hz. Additionally, the analyses predicted stress levels in the tape springs when folded and performed a failure analysis. Prototype model deployment tests validated that the sunshield structure could deploy successfully, overcoming its own weight and internal friction without sustaining damage. The structure also maintained good stiffness in both the folded and deployed states, ensuring the stable shape of the multilayer membrane. This stability fulfills the requirements for stray light suppression and thermal protection for space cameras.