Analysis of Star Identification Algorithms Due to Uncompensated
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Utah State University DigitalCommons@USU All Graduate Theses and Dissertations Graduate Studies 5-2013 Analysis of Star Identification Algorithms due ot Uncompensated Spatial Distortion Steven Paul Brätt Utah State University Follow this and additional works at: https://digitalcommons.usu.edu/etd Part of the Mechanical Engineering Commons Recommended Citation Brätt, Steven Paul, "Analysis of Star Identification Algorithms due ot Uncompensated Spatial Distortion" (2013). All Graduate Theses and Dissertations. 1714. https://digitalcommons.usu.edu/etd/1714 This Thesis is brought to you for free and open access by the Graduate Studies at DigitalCommons@USU. It has been accepted for inclusion in All Graduate Theses and Dissertations by an authorized administrator of DigitalCommons@USU. For more information, please contact [email protected]. ANALYSIS OF STAR IDENTIFICATION ALGORITHMS DUE TO UNCOMPENSATED SPATIAL DISTORTION by Steven P. Brätt A thesis submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE in Mechanical Engineering Approved: Dr. R. Rees Fullmer Dr. Charles M. Swenson Major Professor Committee Member Dr. David Geller Dr. Mark R. McLellan Committee Member Vice President for Research and Dean of the School of Graduate Studies UTAH STATE UNIVERSITY Logan, Utah 2013 ii Copyright © Steven Paul Brätt 2013 All Rights Reserved iii ABSTRACT Analysis of Star Identification Algorithms due to Uncompensated Spatial Distortion by Steven Paul Brätt, Master of Science Utah State University, 2013 Major Professor: Dr. Rees Fullmer Department: Mechanical and Aerospace Engineering With the evolution of spacecraft systems, we see the growing need for smaller, more affordable, and robust spacecrafts that can be jettisoned with ease and sent to sites to perform a myriad of operations that a larger craft would prohibit, or that can be quickly manipulated from performing one task into another. The developing requirements have led to the creation of CubeSats. The question then remains, how to navigate the expanse of space with such a minute spacecraft? A solution to this is using the stars themselves as a means of navigation. This can be accomplished by measuring the angular separation between illuminated pixels in a camera image and associating the pixels with a corresponding star. Once identified, the spacecraft can obtain a quaternion solution to pinpoint its position and facing. A series of star identification algorithms called Lost in Space Algorithms (LISAs) are used to identify these pixels as stars in an image and assess the accuracy and probability of error associated with each algorithm. This is done by creating various images from a simulated camera program, using MATLAB as the program interface, along with images of actual stars in the night sky containing uncompensated error data taken with an Aptina camera. It is shown how suitable these algorithms are for use in space navigation, what constraints and impediments each have, and if low quality imagers can be used to determine attitude using these LISA’s. (221 pages) iv PUBLIC ABSTRACT Analysis of Star Identification Algorithms due to Uncompensated Spatial Distortion by Steven Paul Brätt, Master of Science Utah State University, 2013 Major Professor: Dr. Rees Fullmer Department: Mechanical and Aerospace Engineering With the evolution of spacecraft systems, we see the growing need for smaller, more affordable, and robust spacecrafts that can be jettisoned with ease and sent to sites to perform a myriad of operations that a larger craft would prohibit, or that can be quickly manipulated from performing one task into another. The developing requirements have led to the creation of Nano-Satellites, or CubeSats. The question then remains, how to navigate the expanse of space with such a minute spacecraft? A solution to this is using the stars themselves as a means of navigation. This can be accomplished by measuring the distance between stars in a camera image and determining the stars’ identities. Once identified, the spacecraft can obtain its position and facing. A series of star identification algorithms called Lost in Space Algorithms (LISAs) are used to recognize the stars in an image and assess the accuracy and error associated with each algorithm. This is done by creating various images from a simulated camera, using a program called MATLAB, along with images of actual stars with uncompensated errors. It is shown how suitable these algorithms are for use in space navigation, what constraints and impediments each have, and if low quality cameras using these algorithms can solve the Lost in Space problem. (221 pages) v ACKNOWLEDGMENTS There have been many people who have made a great impact on my life and have helped me achieve my goals and pushed me to excel. To my wonderful professor, Dr. Rees Fullmer, I’d like to thank you for your constant support and input as I’ve worked to complete this thesis and finish my master’s program. You have helped me improve dramatically in my abilities as a researcher and engineer. I’d like to thank your wife who was kind enough to let you spend so much of your time helping me. To David Fowler, a good friend and great co-worker; thank you for your help and friendship as we worked together on both our research theses. You’ve helped me understand much more than you know. I would like to say a special word of gratitude to my marvelous parents, Glenn and Odile, and my family who were always there to encourage me to pursue my dreams and ambitions. Thank you for your love, your prayers, and for the person you have helped me to become. Steven Paul Brätt vi CONTENTS Page ABSTRACT .................................................................................................................................................. iii PUBLIC ABSTRACT ....................................................................................................................................iv ACKNOWLEDGMENTS ............................................................................................................................... v LIST OF TABLES .......................................................................................................................................... x LIST OF FIGURES ........................................................................................................................................xi NOMENCLATURE ................................................................................................................................... xvii CHAPTER 1. INTRODUCTION ..................................................................................................................... 1 I. Overview ............................................................................................................................ 1 II. Star Cameras ....................................................................................................................... 1 III. Star Fields and Identification .............................................................................................. 2 IV. Commercial Cameras .......................................................................................................... 3 V. Thesis Statement and Objectives ........................................................................................ 4 A. Thesis Statement ...................................................................................................4 B. Objectives .............................................................................................................4 2. STAR CATALOGS AND IDENTIFICATION METHODS EXAMINED .............................. 6 I. Star Catalogs ....................................................................................................................... 6 A. Star Databases ......................................................................................................7 1. Henry Draper Database ..........................................................................7 2. PPM Database ........................................................................................7 3. Hipparcos-Tycho Databases ..................................................................7 B. Main Identification Catalog ..................................................................................8 II. Star Identification Algorithms Reviewed ........................................................................... 9 A. Gotlieb ..................................................................................................................9 B. Groth ................................................................................................................... 10 C. Kosik .................................................................................................................. 10 D. Anderson ............................................................................................................ 11 E. Renken ................................................................................................................ 11 F. Liebe ................................................................................................................... 12 G. Baldini ................................................................................................................ 13 H. Scholl .................................................................................................................. 14 I. Ketchum ............................................................................................................