{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T16:12:49Z","timestamp":1778775169069,"version":"3.51.4"},"reference-count":25,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2019,3,6]],"date-time":"2019-03-06T00:00:00Z","timestamp":1551830400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["U1537205"],"award-info":[{"award-number":["U1537205"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Defence Basic Scientific Research Project","award":["JCKY2014203A001"],"award-info":[{"award-number":["JCKY2014203A001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Automatic joint detection is of vital importance for the teaching of robots before welding and the seam tracking during welding. For narrow butt joints, the traditional structured light method may be ineffective, and many existing detection methods designed for narrow butt joints can only detect their 2D position. However, for butt joints with narrow gaps and 3D trajectories, their 3D position and orientation of the workpiece surface are required. In this paper, a vision based detection method for narrow butt joints is proposed. A crosshair laser is projected onto the workpiece surface and an auxiliary light source is used to illuminate the workpiece surface continuously. Then, images with an appropriate grayscale distribution are grabbed with the auto exposure function of the camera. The 3D position of the joint and the normal vector of the workpiece surface are calculated by the combination of the 2D and 3D information in the images. In addition, the detection method is applied in a robotic seam tracking system for GTAW (gas tungsten arc welding). Different filtering methods are used to smooth the detection results, and compared with the moving average method, the Kalman filter can reduce the dithering of the robot and improve the tracking accuracy significantly.<\/jats:p>","DOI":"10.3390\/s19051144","type":"journal-article","created":{"date-parts":[[2019,3,7]],"date-time":"2019-03-07T10:52:22Z","timestamp":1551955942000},"page":"1144","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":58,"title":["A Vision Based Detection Method for Narrow Butt Joints and a Robotic Seam Tracking System"],"prefix":"10.3390","volume":"19","author":[{"given":"Boce","family":"Xue","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China"},{"name":"Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3281-8686","authenticated-orcid":false,"given":"Baohua","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China"},{"name":"Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guodong","family":"Peng","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China"},{"name":"Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yanjun","family":"Gao","sequence":"additional","affiliation":[{"name":"Capital Aerospace Machinery Ltd., Beijing 100076, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhijie","family":"Tian","sequence":"additional","affiliation":[{"name":"Capital Aerospace Machinery Ltd., Beijing 100076, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dong","family":"Du","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China"},{"name":"Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guoqing","family":"Wang","sequence":"additional","affiliation":[{"name":"Capital Aerospace Machinery Ltd., Beijing 100076, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,3,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Hong, Y., Chang, B., Peng, G., Yuan, Z., Hou, X., Xue, B., and Du, D. 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