{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T21:45:17Z","timestamp":1773956717834,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2024,8,8]],"date-time":"2024-08-08T00:00:00Z","timestamp":1723075200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["417002380"],"award-info":[{"award-number":["417002380"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Micro-Computed Tomography (\u00b5CT) systems are used for examining the internal structures of various objects, such as material samples, manufactured parts, and natural objects. Resolving fine details or performing accurate geometric measurements in the voxel data critically depends on the precise calibration of the \u00b5CT systems geometry. This paper presents a calibration method for \u00b5CT systems using projections of a calibration phantom, where the coordinates of the phantom are initially unknown. The approach involves detecting and tracking steel ball bearings and adjusting the unknown system geometry parameters using non-linear least squares optimization. Multiple geometric models are tested to verify their suitability for a self-calibration approach. The implementation is tested using a calibration phantom captured at different magnifications. The results demonstrate the system\u2019s capability to determine the geometry model parameters with a remaining error on the detector between 0.27 px and 0.18 px. Systematic errors that remain after calibration, as well as changing parameters due to system instabilities, are investigated. The source code of this work is published to enable further research.<\/jats:p>","DOI":"10.3390\/s24165139","type":"journal-article","created":{"date-parts":[[2024,8,8]],"date-time":"2024-08-08T15:04:24Z","timestamp":1723129464000},"page":"5139","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Investigations into the Geometric Calibration and Systematic Effects of a Micro-CT System"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-1588-117X","authenticated-orcid":false,"given":"Matthias","family":"Hardner","sequence":"first","affiliation":[{"name":"Institute of Photogrammetry and Remote Sensing, TUD Dresden University of Technology, 01069 Dresden, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5649-6461","authenticated-orcid":false,"given":"Frank","family":"Liebold","sequence":"additional","affiliation":[{"name":"Institute of Photogrammetry and Remote Sensing, TUD Dresden University of Technology, 01069 Dresden, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0715-6118","authenticated-orcid":false,"given":"Franz","family":"Wagner","sequence":"additional","affiliation":[{"name":"Institute of Photogrammetry and Remote Sensing, TUD Dresden University of Technology, 01069 Dresden, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9034-3469","authenticated-orcid":false,"given":"Hans-Gerd","family":"Maas","sequence":"additional","affiliation":[{"name":"Institute of Photogrammetry and Remote Sensing, TUD Dresden University of Technology, 01069 Dresden, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"230","DOI":"10.1016\/j.precisioneng.2016.03.001","article-title":"Evaluating the effects of detector angular misalignments on simulated computed tomography data","volume":"45","author":"Ferrucci","year":"2016","journal-title":"Precis. 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