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Integration of Orbital and Ground Data for Martian Crater Mapping A Integration of Orbital and Ground Data for Martian Crater Mapping A Methodological Study at Santa Maria Crater Thesis Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in the Graduate School of The Ohio State University By Rui Wu, M.S. Graduate Program in Civil Engineering The Ohio State University 2012 Thesis Committee: Rongxing Li, Advisor Carolyn Merry Alper Yilmaz Copyright by Rui Wu 2012 Abstract High-quality mapping products for Martian craters are helpful data sources for scientists to explore the red planet in many fields. This thesis focuses on integrating orbital imagery and ground imagery to generate high-quality Martian crater mapping products. The usability of the proposed method is validated mainly at one crater – Santa Maria Crater. The orbital imagery comes from the High Resolution Instrument Scientific Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter (MRO) satellite. The ground imagery comes from the Navigation cameras (Navcams) and Panoramic cameras (Pancams) images taken by the Opportunity rover in Mars Exploration Rover (MER) mission. In this thesis, important processes during the mapping will be introduced, discussed, and analyzed, including interest point extraction, image network construction, bundle adjustment (BA), dense matching, and product generation. Some new methods during these processes are proposed to improve the quality of the final products. The wide-baseline method is used in an unprecedented way in the tie point selection to guarantee the accuracy of the distant tie points. An integrated bundle adjustment replaces the former incremental bundle adjustment used in the MER mission for large crater mapping. Matching in the featureless areas is also discussed in this paper. The theoretical analysis and the improved results of these proposed ii methods are highlighted with details. The mapping products at Santa Maria Crater are listed to illustrate the feasibility of the proposed mapping methods. A reasonable conclusion is that the methods mentioned in this thesis work smoothly at Santa Maria Crater. iii Dedication To my parents –for giving me your eyes iv Acknowledgements Foremost, I want to thank my advisor, Dr. Rongxing Li, for leading me and guiding me in the Master study and research. His thorough knowledge in the research and endless enthusiasm for the job support and encourage me in this two-year adventure. Without his guidance, I could never take the progress in the area of photogrammetry and mapping, let alone writing this thesis to get the Master degree. Besides my advisor, I would give my sincere thank to the rest of my thesis committees: Dr. Carolyn Merry and Dr. Yilmaz, for their continuous encouragement and advising. My gratitude also goes to Dr. Kaichang Di, Dr. Shaoming Zhang, and Dr. Xuelian Meng in the Mapping and GIS Lab, who helped me not only in the research with their expertise, but also in my life with their rich experience. I also want to thank my coworkers and friends in the Mapping and GIS Lab: Liwen Lin, Wei Wang, Onur Karahayit, Ding Li, Shaojun He, I-Chee Lee, Jiangye Yuan, Justin Crawford, Weishu Gong, and Leslie Smith, for the inspiring tutorials, for the sleepless nights we worked together for the project, and for the laughter scattered in every single day of the last two years. And I want to express my deepest thank to my friend Min Wang. Her comfort is the life saver for me when I feel hopelessness and desperation. I could not be the current me without her encouragement. v Last but not least, I must thank my greatest parents. Their selfless support has been, and will always be my source of spiritual strength. The research is supported by the Mars Data Analysis Program (MDAP) from NASA. vi Vita 2004.......................................................Luhe First High School 2008.......................................................B.S. GIS, Peking University 2010.......................................................M.E. Photogrammetry and Remote Sensing, Peking University 2010 to present ......................................Graduate Research Associate, Department of Civil Engineering, The Ohio State University Publications Li, R., R. Wu, and X. Meng 2012. Wide-Baseline Mapping of Martian Craters: A Comparison Study at Santa Maria Crater. ASPRS 2012 Annual Conference, 19-23 March, Sacramento, CA. Abstract no. 345409 (1 p.) and presentation. Fields of Study Major Field: Civil Engineering vii Table of Contents Abstract ........................................................................................................................................ ii Dedication ................................................................................................................................... iv Acknowledgements ...................................................................................................................... v Vita ...................................................................................................................................... vii List of Tables ............................................................................................................................... ix List of Figures .............................................................................................................................. x Chapter 1: Introduction ................................................................................................................ 1 Chapter 2: Background of Orbital and Ground Data ................................................................... 8 Chapter 3: Construction of Image Network ............................................................................... 22 Chapter 4: Integrated Bundle Adjustment.................................................................................. 36 Chapter 5: Mapping Product Generation ................................................................................... 56 Chapter 6: Conclusions .............................................................................................................. 70 References .................................................................................................................................. 72 viii List of Tables Table 2-1. Important parameters of the camera system. ............................................ 11 Table 2-2. An example of RMC sequence. ................................................................17 Table 4-1. The statistics of the inconsistencies between features ..............................51 Table 4-2. The statistics of the consistency of features and rover positions ..............53 Table 5-1. The comparison on the dimension of Santa Maria Crater. .......................68 ix List of Figures Figure 1-1. The workflow of Martian crater mapping. ................................................6 Figure 2-1. HiRISE focal plane assembly layout. ........................................................9 Figure 2-2. Mars body-fixed reference system. .........................................................13 Figure 2-3. Landing site cartographic coordinate system. .........................................14 Figure 2-4. Site frame. ...............................................................................................15 Figure 2-5. Multiple instances of site frame. .............................................................16 Figure 2-6. Calculation of current position. ...............................................................20 Figure 3-1. Three types of tie points. .........................................................................23 Figure 3-2. Parallaxes of all candidate matching points and the parallax curve. .......26 Figure 3-3. The same feature observed from two different rover positions. .............27 Figure 3-4. Finding the feature correspondence by overlaying orthoimages. ...........28 Figure 3-5. The effect of baseline length on the accuracy .........................................30 Figure 3-6. The distribution of rover positions near ..................................................31 Figure 3-7. The result of rigid transformation when hard-baseline ...........................33 Figure 3-8. The construction of wide-baseline tie point selection. ............................34 Figure 3-9. The result of rigid transformation when wide-baseline ..........................34 Figure 4-1. Geometry of the collinearity. ...................................................................37 Figure 4-2. Typical landforms in Gusev Crater and Meridiani Planum. ....................43 Figure 4-3. The histograms of traverse in Gusev Crater and Meridiani Planum. ......44 x Figure 4-4. Initialization of a rover position through feature comparison .................46 Figure 4-5. Shadows and shadings in HiRISE images of Martian craters. ................48 Figure 4-6. The comparison between the DTMs generated from HiRISE images. ...49 Figure 4-7. Inconsistencies between features among multiple rover positions .........51 Figure 4-8. The consistency of rover positions and features between .......................53 Figure 5-1. Rules for choosing dense matching method. ...........................................58 Figure 5-2. Geographe Crater with its blocked area. .................................................59 Figure 5-3. The dense matching points in Santa Maria Crater. ..................................61 Figure 5-4. Feature Comparison between the DTM of Santa Maria Crater ..............62 Figure 5-5. The
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