{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:15:21Z","timestamp":1760238921881,"version":"build-2065373602"},"reference-count":52,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2020,9,16]],"date-time":"2020-09-16T00:00:00Z","timestamp":1600214400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"TBE, EDP and ANEEL - The Brazilian Regullaroty Agency of Electricity","award":["PD-02651-0013\/2017"],"award-info":[{"award-number":["PD-02651-0013\/2017"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The increase in the development of digital twins brings several advantages to inspection and maintenance, but also new challenges. Digital models capable of representing real equipment for full remote inspection demand the synchronization, integration, and fusion of several sensors and methodologies such as stereo vision, monocular Simultaneous Localization and Mapping (SLAM), laser and RGB-D camera readings, texture analysis, filters, thermal, and multi-spectral images. This multidimensional information makes it possible to have a full understanding of given equipment, enabling remote diagnosis. To solve this problem, the present work uses an edge-fog-cloud architecture running over a publisher-subscriber communication framework to optimize the computational costs and throughput. In this approach, each process is embedded in an edge node responsible for prepossessing a given amount of data that optimizes the trade-off of processing capabilities and throughput delays. All information is integrated with different levels of fog nodes and a cloud server to maximize performance. To demonstrate this proposal, a real-time 3D reconstruction problem using moving cameras is shown. In this scenario, a stereo and RDB-D cameras run over edge nodes, filtering, and prepossessing the initial data. Furthermore, the point cloud and image registration, odometry, and filtering run over fog clusters. A cloud server is responsible for texturing and processing the final results. This approach enables us to optimize the time lag between data acquisition and operator visualization, and it is easily scalable if new sensors and algorithms must be added. The experimental results will demonstrate precision by comparing the results with ground-truth data, scalability by adding further readings and performance.<\/jats:p>","DOI":"10.3390\/s20185296","type":"journal-article","created":{"date-parts":[[2020,9,16]],"date-time":"2020-09-16T10:30:12Z","timestamp":1600252212000},"page":"5296","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["A Heterogeneous Edge-Fog Environment Supporting Digital Twins for Remote Inspections"],"prefix":"10.3390","volume":"20","author":[{"given":"Luiz A. Z. da","family":"Silva","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering, Federal University of Juiz de Fora, Juiz de Fora 36036-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2576-2760","authenticated-orcid":false,"given":"Vinicius F.","family":"Vidal","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Federal University of Juiz de Fora, Juiz de Fora 36036-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2735-4792","authenticated-orcid":false,"given":"Leonardo M.","family":"Hon\u00f3rio","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Federal University of Juiz de Fora, Juiz de Fora 36036-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2312-7042","authenticated-orcid":false,"given":"M\u00e1rio A. R.","family":"Dantas","sequence":"additional","affiliation":[{"name":"Department of Computer Science, Federal University of Juiz de Fora, Juiz de Fora 36036-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6916-700X","authenticated-orcid":false,"given":"Milena Faria","family":"Pinto","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Federal Center for Technological Education of Rio de Janeiro, Rio de Janeiro 20271-110, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1380-971X","authenticated-orcid":false,"given":"Miriam","family":"Capretz","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Faculty of Engineering, Western University, London, ON N6G 1G8, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Duan, P., Pang, L., Jin, Y., Guo, Q., and Jia, Z.X. 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