{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,7]],"date-time":"2026-01-07T17:22:08Z","timestamp":1767806528856,"version":"3.49.0"},"reference-count":34,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,7]],"date-time":"2026-01-07T00:00:00Z","timestamp":1767744000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100015491","name":"Autonomous Deployment Project of Shanghai Institute of Technical Physics, Chinese Academy of Sciences","doi-asserted-by":"publisher","award":["E481287070"],"award-info":[{"award-number":["E481287070"]}],"id":[{"id":"10.13039\/501100015491","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The key components of spacecraft are typically present as circular or near-circular structures, and their precise and rapid extraction is essential for spacecraft attitude estimation. In response to the high precision and robust detection of ellipse components on space non-cooperative targets such as spacecraft docking rings, this paper proposes an efficient and robust ellipse detection method. This method first uses the arc-support line segment method to extract ellipse arc segments and then employs a hierarchical quadrant division strategy with a \u201ccoarse-to-fine\u201d approach, integrating multiple constraints such as angle, quadrant, and relative position to combine arc segments and generate ellipse candidates. It uses a comprehensive score based on edge density, global coverage and local continuity to select the optimal ellipse from among the valid ellipses. Finally, a dynamic arc segment pruning method is introduced to dynamically remove relevant arcs from optimal ellipses, obtaining high-quality and non-redundant detection results. This method can achieve robust ellipse detection even when docking ring contours are partially obscured by shadows from robotic arms or nozzles.<\/jats:p>","DOI":"10.3390\/s26020396","type":"journal-article","created":{"date-parts":[[2026,1,7]],"date-time":"2026-01-07T16:14:12Z","timestamp":1767802452000},"page":"396","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["An Efficient and Robust Ellipse Detection Method for Spacecraft Docking Rings in Complex Scenes"],"prefix":"10.3390","volume":"26","author":[{"given":"Qi","family":"Wu","sequence":"first","affiliation":[{"name":"Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"},{"name":"Shanghai Integrated Innovation Center for Space Optoelectronic Perception, Shanghai 200083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"An","family":"Shu","sequence":"additional","affiliation":[{"name":"Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"Shanghai Integrated Innovation Center for Space Optoelectronic Perception, Shanghai 200083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Haodong","family":"Pei","sequence":"additional","affiliation":[{"name":"Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"Shanghai Integrated Innovation Center for Space Optoelectronic Perception, Shanghai 200083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kun","family":"Yu","sequence":"additional","affiliation":[{"name":"Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"Shanghai Integrated Innovation Center for Space Optoelectronic Perception, Shanghai 200083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Muyun","family":"Luo","sequence":"additional","affiliation":[{"name":"Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"},{"name":"Shanghai Integrated Innovation Center for Space Optoelectronic Perception, Shanghai 200083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yunmeng","family":"Liu","sequence":"additional","affiliation":[{"name":"Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"Shanghai Integrated Innovation Center for Space Optoelectronic Perception, Shanghai 200083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.paerosci.2014.03.002","article-title":"A review of space robotics technologies for on-orbit servicing","volume":"68","author":"Ma","year":"2014","journal-title":"Prog. 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