CTM Boom Deployment Mechanism with Integrated Boom Root Deployment for Increased Stiffness of the Boom-to-Spacecraft Interface

Abstract

CTMs (Collapsible Tube Masts) are well known for small and medium sized solar sails as they can create huge and stiff sail backbone structures out of a very small mass. But one key issue with those masts is the need for a full deployment of the booms cross section in order to generate the full stiffness. Close to the deployment mechanism the stiffness is significantly decreased. Usual mechanisms try to counteract this drawback by guiding rollers or surfaces that support the boom in this weak transition zone. The underlying paper will present a different approach: The boom spool of the novel deployment mechanism contains a simple but reliable mechanism that is triggered at the end of the longitudinal deployment. This inner mechanism deploys the booms cross section and locks the boom spool into the outer walls of the surrounding structure. The result is a boom deployment mechanism that supports the utilization of the full potential of the CTMs.