Design and Testing of Self-Deploying Membrane Optic Support Structure Using Rollable Composite Tape Springs

Abstract

The detail mechanical design of a freely-deploying support structure that positions and tensions a membrane primary optic was presented. Rollable composite tape spring members were the main components of the structure that provided the deployment force, controlled the deployment kinematics, and reacted the membrane tension load at full deployment. A simple constraint mechanism locks each tape spring hub in the stowed configuration, and simultaneously releases each hub for deployment. The detailed design and analysis of the self-deployable tape spring mechanism shows that the system provides the necessary deployment force and buckling resistance with margin. A prototype unit was fabricated and deployment tests performed. The deployment tests successfully demonstrate a new architecture based on rolled and freely deployed composite tape spring members that achieves simultaneous deployment in three dimensions without mechanical synchronization.