Date of Award


Document Type


Degree Name

Master of Science


Department of Aeronautics and Astronautics

First Advisor

Gregory S. Agnes, PhD


Tightening space budgets and stagnating spacelift capabilities are driving the Air Force and other space agencies to focus on inflatable technology as a reliable, inexpensive means of deploying large structures in orbit. Recent improvements in rigidization techniques make the use these inflatable structures feasible for a growing number of missions. For many of these missions, the primary design requirement is dimensional accuracy of the structure. Finite element analysis offers a means of predicting structural behavior in orbit. The analysis requires knowledge of external loads. This thesis examines the environmental disturbances which act upon large, orbiting structures. Calculations are made on a base model to relate the torques generated by these disturbances to the orbital altitude. This facilitates identification of the critical loads. An environmental disturbance model is then developed in MATLAB. The model calculates the critical loads on each element of a faceted structure as it propagates through its orbit. A basic structure is defined and run through the model. Results and analysis for various orbits are presented to verify accuracy of the code and validate the derived torque-altitude relationships.

AFIT Designator


DTIC Accession Number