Mechanism Design and Testing of a Se lf-Deploying Structure Using Flexible Composite Tape Springs Joseph N. Footdale*and Thomas W. Murphey** Abstract The detailed mechanical design of a novel deployable support structure that positions and tensions a  membrane optic for space imagining applications is presented. This is a complex three-dimensional deployment using freely deploying rollable composite tape spring booms that become load bearing  structural members at full deployment. The deployment tests successfully demonstrate a new architecture based on rolled and freely deployed composite tape spring members that achieve simultaneous deployment without mechanical synchronization. Proper design of the flexible component mounting interface and constraint systems, which were critical in achieving a functioning unit, are described. These  flexible composite components have much potential for advancing the state of the art in deployable structures, but have yet to be widely adopted. This paper demonstrates the feasibility and advantages of implementing flexible composite components, including the design details on how to integrate with required traditional mechanisms.  Introduction Current efforts in advancing the art of deployable structures include developing deployment architectures  that maximize the packaging efficiency while minimizing mass and satisfying dimensional stability constraints. A number of developed and conceptual architectures are making such advancements with  the implementation of flexible Fiber Reinforced Polymer (FRP) composite laminate components in place  of traditional hinge and latching mechanisms. The Air Force Research Laboratory (AFRL) Space Vehicles Directorate has developed multiple deployable architectures [1-3], including a boom [4] that employed rollable composite tape spring members. These example structures also utilized the stored strain energy  of the structure in the packaged configuration to provide the motive force to drive the deployment, eliminating the need for external energy sources (motors or springs for example). The tape spring members are similar in shape and functionality as the Storable Tubular Extendable Member (STEM) boom [5]. The difference lies in the engineered laminate design that allows the tape spring to tightly wrap  around a cylindrical drum without requiring containment mechanisms or shroud to prevent radial billowingduring deployment. FRP composite laminates are the preferred material because of the increased strain  capability, higher modulus, lower mass, and increased dimensional stability over conventionally used metallic materials for flexure applications. This paper presents the design and testing of a novel, self-deployable support structure that implements  rollable composite tape spring members. The structure is a departure from existing architectures due to the synchronous deployment of the structure in three dimensions simultaneously. The synchronous deployment is achieved without any mechanical components to enforce the desired kinematics. This was accomplished through a combination of a tape spring laminate and geometry and constraint mechanism designs. When compared to the relatively large number of mechanisms and support components required in traditional systems to enable the deployment of a three-dimensional structure, the freely-deploying  architecture presented offers significant advantages with respect to complexity (and associated cost) and performance. * LoadPath, Albuquerque, NM **High Strain Dynamics, Phoenix, NY /g51/g85/g82/g70/g72/g72/g71/g76/g81/g74/g86/g3/g82/g73/g3/g87/g75/g72/g3/g23/g21/g81/g71/g3/g36/g72/g85/g82/g86/g83/g68/g70/g72/g3/g48/g72/g70/g75/g68/g81/g76/g86/g80/g86/g3/g54/g92/g80/g83/g82/g86/g76/g88/g80/g15/g3/g49/g36/g54/g36/g3/g42/g82/g71/g71/g68/g85 /g71/g3/g54/g83/g68/g70/g72/g3/g41/g79/g76/g74/g75/g87/g3/g38/g72/g81/g87/g72/g85/g15/g3/g48/g68/g92/g3/g20/g23/g16/g20/g25/g15/g3/g21/g19/g20/g23/g3 497