Date of Award


Document Type


Degree Name

Master of Science


Department of Aeronautics and Astronautics

First Advisor

Richard G. Cobb, PhD


Many recent space technology concepts require large space structures such as solar arrays and large aperture antennas; however, tight constraints on payload mass and volume often preclude their launch. Employing inflatable, rigidizable structures can reduce mass and volume while providing sufficient packing flexibility and structural stiffness. AFIT has developed RIGEX to flight-test this type of structure. RIGEX will test the deployment and structural characteristics of three thermoplastic composite Sub-Tg tubes. Once launched on the Space Shuttle in 2007, the spaceflight results will be compared to lab data to validate on-orbit reliability and ground test methods. This paper documents three main RIGEX development items: the Space Shuttle integration process, random vibration testing of the oven assembly, and development and application of the RIGEX structural model. The RIGEX launch integration process has been laid out and the first milestones, the RIGEX Preliminary Design Review and Phase 0/I Safety Review, were successfully completed in September 2005. Subsequently, random vibration testing of the prototype RIGEX oven assembly validated its structural integrity. Furthermore, a RIGEX structural model was developed using the finite element approach and NX Nastran for FEMAP software. The RIGEX FEM produced a first natural frequency of 242 Hz, meeting the NASA requirement with a margin of over 140 Hz. Overall, the RIGEX structural design has rapidly matured, meeting all NASA requirements thus far.

AFIT Designator


DTIC Accession Number