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A Methodology for the Optimization of Disaggregated Space System Conceptual Designs Robert E Air Force Institute of Technology AFIT Scholar Theses and Dissertations Student Graduate Works 6-18-2015 A Methodology for the Optimization of Disaggregated Space System Conceptual Designs Robert E. Thompson Follow this and additional works at: https://scholar.afit.edu/etd Recommended Citation Thompson, Robert E., "A Methodology for the Optimization of Disaggregated Space System Conceptual Designs" (2015). Theses and Dissertations. 199. https://scholar.afit.edu/etd/199 This Dissertation is brought to you for free and open access by the Student Graduate Works at AFIT Scholar. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of AFIT Scholar. For more information, please contact [email protected]. A METHODOLOGY FOR THE OPTIMIZATION OF DISAGGREGATED SPACE SYSTEM CONCEPTUAL DESIGNS DISSERTATION Robert E. Thompson, Major, USAF AFIT-ENV-DS-15-J-062 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio DISTRIBUTION STATEMENT A. APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. The views expressed in this thesis are those of the author and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the United States Government. This material is declared a work of the U.S. Government and is not subject to copyright protection in the United States. AFIT-ENV-DS-15-J-062 A METHODOLOGY FOR THE OPTIMIZATION OF DISAGGREGATED SPACE SYSTEM CONCEPTUAL DESIGNS DISSERTATION Presented to the Faculty Department of Systems Engineering and Management Graduate School of Engineering and Management Air Force Institute of Technology Air University Air Education and Training Command In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Robert E. Thompson, BS Major, USAF June 2015 DISTRIBUTION STATEMENT A. APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. AFIT-ENV-DS-15-S-062 A METHODOLOGY FOR THE OPTIMIZATION OF DISAGGREGATED SPACE SYSTEM CONCEPTUAL DESIGNS Robert E. Thompson, MS Major, USAF Committee Membership: Dr. John M. Colombi Chair Dr. Jonathan T. Black Member Dr. Bradley J. Ayres Member AFIT-ENV-DS-15-J-062 Abstract Optimal design techniques have proven to be an effective systems engineering tool. Using systems architecture as the foundation, this research explores the use of mixed variable optimization models for synthesizing and evaluating disaggregated space system concepts. Model-based conceptual design techniques are used to identify and assess system architectures based upon estimated system cost, performance trades, and cost risk. The Disaggregated Integral System Concept Optimization (DISCO) methodology is introduced, and then applied to representative space-based missions. Several results are obtained that indicate significant cost effectiveness gains from the optimization of multi- orbit and multi-function/multi-orbit disaggregated space systems. Savings of $82 million are identified for an optimized fire detection system. Savings of $5.7 billion are identified for an optimized defense weather system. This optimized defense weather system was also shown to have a reduction in cost risk due to failures of $117 million. The general methodology has broad applicability for model-based conceptual design (MBCD) of many system types, but is particularly useful for dynamic disaggregated space systems. iv Acknowledgments I would like to express my sincere appreciation to my faculty advisor, Dr. John Colombi, for his guidance and support throughout the course of this research effort. His insight, experience, and guidance were instrumental. I would also like to thank my wife and daughters for their loving support throughout the many long days and nights. Additionally I would like to thank Donald Boucher and other members of the Remote Sensing System Directorate at the Space and Missiles Systems Center for the support provided in this endeavor. Robert E. Thompson v Table of Contents Page Abstract .............................................................................................................................. iv Table of Contents ............................................................................................................... vi List of Figures .................................................................................................................. viii List of Tables .......................................................................................................................x I. Introduction .....................................................................................................................1 Problem.........................................................................................................................1 Research Objectives .....................................................................................................2 Research Questions/Hypotheses ...................................................................................3 Methodology Overview ................................................................................................4 Assumptions/Limitations ..............................................................................................6 Implications ..................................................................................................................8 Preview .......................................................................................................................10 II. Methodology Development and Introduction ...............................................................12 Introduction ................................................................................................................12 Background.................................................................................................................13 DISCO Methodology..................................................................................................20 Develop assessment/optimization models ..................................................................27 Evaluate solutions and update architecture ................................................................31 Fire detection problem ................................................................................................34 Results ........................................................................................................................49 Discussion...................................................................................................................51 III. Multi-function Optimization and Sensitivity Analysis Methods .................................53 Introduction ................................................................................................................53 vi Methodology...............................................................................................................57 Application .................................................................................................................65 Results ........................................................................................................................82 Conclusion ..................................................................................................................90 Chapter III Appendix A - Optimization formulation .................................................91 Chapter III Appendix B - Example sensor performance calculations ........................93 IV. Stochastic Analysis Methods .......................................................................................99 Introduction ................................................................................................................99 Background...............................................................................................................101 Methods ....................................................................................................................104 Application ...............................................................................................................113 Results ......................................................................................................................126 Summary...................................................................................................................135 V. Conclusions and Recommendations ..........................................................................137 Conclusions of Research ..........................................................................................137 Significance of Research ..........................................................................................139 Recommendations for Action ...................................................................................141 Recommendations for Future Research....................................................................143 Summary...................................................................................................................146 Appendix A – Expanded Space Systems Optimization Literature Review .....................147 Previous Space system optimization research ..........................................................148 Appendix B – Additional Methodology Development ....................................................160 Bibliography ....................................................................................................................166
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