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Cubesat Attitude Determination and Control System (ADACS) Characterization and Testing for Rendezvous and Proximity Operations (RPO)

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Cubesat Attitude Determination and Control System (ADACS) Characterization and Testing for Rendezvous and Proximity Operations (RPO) Air Force Institute of Technology AFIT Scholar Theses and Dissertations Student Graduate Works 3-2021 CubeSat Attitude Determination and Control System (ADACS) Characterization and Testing for Rendezvous and Proximity Operations (RPO) Steven T. Bednarski Follow this and additional works at: https://scholar.afit.edu/etd Part of the Aerospace Engineering Commons Recommended Citation Bednarski, Steven T., "CubeSat Attitude Determination and Control System (ADACS) Characterization and Testing for Rendezvous and Proximity Operations (RPO)" (2021). Theses and Dissertations. 4970. https://scholar.afit.edu/etd/4970 This Thesis 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]. CubeSat Attitude Determination and Control System (ADACS) Characterization and Testing for Rendezvous and Proximity Operations (RPO) THESIS Steven T. Bednarski, Captain, USSF AFIT-ENY-MS-21-M-288 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. i The views expressed in this thesis are those of the author and do not reflect the official policy or position of the United States Space Force, 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. i AFIT-ENY-MS-21-M-288 CUBESAT ATTITUDE DETERMINATION AND CONTROL SYSTEM (ADACS) CHARACTERIZATION AND TESTING FOR RENDEZVOUS AND PROXIMITY OPERATIONS (RPO) THESIS Presented to the Faculty Department of Aeronautics and Astronautics 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 Master of Science in Space Systems Steven T. Bednarski, BS Captain, USSF March 2021 DISTRIBUTION STATEMENT A. APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. ii AFIT-ENY-MS-21-M-288 CUBESAT ATTITUDE DETERMINATION AND CONTROL SYSTEM (ADACS) CHARACTERIZATION AND TESTING FOR RENDEZVOUS AND PROXIMITY OPERATIONS (RPO) THESIS Steven T. Bednarski, BA, BS Captain, USSF Committee Membership: Dr. Andrew S. Keys, Ph.D. Chair Dr. Richard G. Cobb, Ph.D. Member Dr. Bradley J. Ayres, Ph.D. Member iii AFIT-ENY-MS-21-M-288 Abstract This research endeavors to evaluate and characterize the performance of CubeSat specific commercial-off-the-shelf (COTS) Attitude Determination and Control Systems (ADACS) for Mission suitability. To ensure COTS components are capable of meeting CubeSat mission requirements, deliberate performance testing of critical CubeSat subsystems in flight-like conditions is essential. This effort focuses on testing the MAI-401 ADACS subsystem as configured to support the Grissom-1 CubeSat mission, as mounted to an air bearing, residing within a 3-axis Helmholtz Cage, and subjected to a simulated magnetic environment of various orbital parameters. A literature review of spacecraft components, prior missions, operations, environmental simulators, and attitude determination and control algorithms informs the tests and assessments described herein. A test plan developed as part of this research exercises and characterizes the MAI-401 ADACS unit for the Grissom-1 mission and serves as a comparative framework for testing additional ADACS offerings such as the BCT XACT ADACS unit. Results include a baseline characterization of COTS ADACS, discussion of currently available ADACS and suitable Mission types, and suggestions for enhanced testing. iv Acknowledgements First and foremost, I would like to thank the ENY Department, and specifically my advisor Dr. Keys for the support and guidance to always keep pushing forward towards success. Dr. Keys’ patience and ability to accept barriers and call an audible mid-stride allowed this research to still have relevance. I would like to thank the fine folks out at the Starfire Optical Range for planting the Advanced Academic Degree seed from the very beginning. The support, encouragement, harassment, mentorship, and constant example of what is possible from the team drove this dream to reality. I would also like to thank the CSRA Staff as without them none of this would be possible. Thanks to Chris Lomanno for spending so much time working the cage, commanding, troubleshooting, and teaching the process to me. Thanks to Sean Miller for making sure my assumptions we valid, to Blake Benton for all the hardware support, and to Cheney Sollenberger and the Software Development team for dropping what you were doing and running down my issues. Finally, I would like to thank my family for the love, encouragement, support, and ultimately understanding through the program. Thank you especially to my wife for taking on way more than her fair share of responsibilities and for keeping our home and way of life in-tact and thank you to my boys for being a constant source of laughter when it was needed most. Steven T. Bednarski v Table of Contents Abstract ................................................................................................................................iv Acknowledgements .............................................................................................................. v I. Introduction ...................................................................................................................... 1 II. Background ..................................................................................................................... 7 2.1 CubeSats .....................................................................................................................7 2.2 Mission Sets and History ........................................................................................10 2.3 Attitude Determination and Control Systems ........................................................14 2.3.1 Attitude Determination .....................................................................................18 2.3.2 Attitude Determination Algorithms.................................................................19 2.3.3 Determination Sensors .....................................................................................22 2.3.4 Attitude Control ................................................................................................26 2.3.5 Control Components.........................................................................................28 2.4 Space Environment and Test Apparatus ................................................................30 2.4.1 Earth’s Geomagnetic Sphere............................................................................31 2.4.2 Helmholtz Coils and Cages ..............................................................................33 2.4.3 Air Bearings ......................................................................................................36 III. Methodology ................................................................................................................ 38 3.1 Mission, Justification, and Available Solutions ....................................................39 3.1.1 Mission ..............................................................................................................42 3.1.2 Justification .......................................................................................................45 3.1.3 ADACS Solutions ............................................................................................46 3.2 Performance Evaluation ..........................................................................................51 3.2.1 Attitude Determination vs. Control Performance ...........................................52 3.2.2 Performance Metrics and Figures of Merit .....................................................53 3.2.3 Data Collection .................................................................................................54 3.3 Experimental Setup .................................................................................................55 3.3.1 Component Frames of Reference ....................................................................61 3.4 Limitations ...............................................................................................................64 IV. Analysis ....................................................................................................................... 67 4.1 Magnetic Field Data Analysis..................................................................................68 4.2 PhaseSpace Motion Capture Data Analysis ............................................................77 4.3 Bias and Gains ..........................................................................................................84 4.4 Conclusion of Test Results ......................................................................................94 V. Conclusion .................................................................................................................... 98 5.1 Summary ..................................................................................................................98 5.2 Conclusion ...........................................................................................................
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