{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T10:34:38Z","timestamp":1790159678610,"version":"4.1.0"},"reference-count":27,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2018,10,11]],"date-time":"2018-10-11T00:00:00Z","timestamp":1539216000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Robotics"],"abstract":"<jats:p>The leaf area is an important plant parameter for plant status and crop yield. In this paper, a low-cost time-of-flight camera, the Kinect v2, was mounted on a robotic platform to acquire 3-D data of maize plants in a greenhouse. The robotic platform drove through the maize rows and acquired 3-D images that were later registered and stitched. Three different maize row reconstruction approaches were compared: reconstruct a crop row by merging point clouds generated from both sides of the row in both directions, merging point clouds scanned just from one side, and merging point clouds scanned from opposite directions of the row. The resulted point cloud was subsampled and rasterized, the normals were computed and re-oriented with a Fast Marching algorithm. The Poisson surface reconstruction was applied to the point cloud, and new vertices and faces generated by the algorithm were removed. The results showed that the approach of aligning and merging four point clouds per row and two point clouds scanned from the same side generated very similar average mean absolute percentage error of 8.8% and 7.8%, respectively. The worst error resulted from the two point clouds scanned from both sides in opposite directions with 32.3%.<\/jats:p>","DOI":"10.3390\/robotics7040063","type":"journal-article","created":{"date-parts":[[2018,10,12]],"date-time":"2018-10-12T02:58:04Z","timestamp":1539313084000},"page":"63","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Leaf Area Estimation of Reconstructed Maize Plants Using a Time-of-Flight Camera Based on Different Scan Directions"],"prefix":"10.3390","volume":"7","author":[{"given":"Manuel","family":"V\u00e1zquez-Arellano","sequence":"first","affiliation":[{"name":"Institute of Agricultural Engineering, University of Hohenheim, Garbenstrasse 9, 70599 Stuttgart, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0158-6456","authenticated-orcid":false,"given":"David","family":"Reiser","sequence":"additional","affiliation":[{"name":"Institute of Agricultural Engineering, University of Hohenheim, Garbenstrasse 9, 70599 Stuttgart, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8275-8840","authenticated-orcid":false,"given":"Dimitrios S.","family":"Paraforos","sequence":"additional","affiliation":[{"name":"Institute of Agricultural Engineering, University of Hohenheim, Garbenstrasse 9, 70599 Stuttgart, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7880-6499","authenticated-orcid":false,"given":"Miguel","family":"Garrido-Izard","sequence":"additional","affiliation":[{"name":"Laboratorio de Propiedades F\u00edsicas (LPF)-TAGALIA, Technical University of Madrid, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hans W.","family":"Griepentrog","sequence":"additional","affiliation":[{"name":"Institute of Agricultural Engineering, University of Hohenheim, Garbenstrasse 9, 70599 Stuttgart, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,11]]},"reference":[{"key":"ref_1","first-page":"58","article-title":"Effect of leaf area on maize productivity","volume":"59","author":"Lambert","year":"2014","journal-title":"Maydica"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"16988","DOI":"10.3390\/s121216988","article-title":"Grapevine yield and leaf area estimation using supervised classification methodology on RGB images taken under field conditions","volume":"12","author":"Diago","year":"2012","journal-title":"Sensors"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2166","DOI":"10.3390\/s110202166","article-title":"3-D modeling of tomato canopies using a high-resolution portable scanning lidar for extracting structural information","volume":"11","author":"Hosoi","year":"2011","journal-title":"Sensors"},{"key":"ref_4","unstructured":"Kazmi, W., Bisgaard, M., Garcia-Ruiz, F., Hansen, K.D., and la Cour-Harbo, A. 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