{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T04:17:26Z","timestamp":1772770646379,"version":"3.50.1"},"reference-count":25,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2024,6,14]],"date-time":"2024-06-14T00:00:00Z","timestamp":1718323200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"CENTRO DE COMPET\u00caNCIA EMBRAPII VIRTUS EM HARDWARE INTELIGENTE PARA IND\u00daSTRIA","award":["055\/2023"],"award-info":[{"award-number":["055\/2023"]}]},{"name":"CENTRO DE COMPET\u00caNCIA EMBRAPII VIRTUS EM HARDWARE INTELIGENTE PARA IND\u00daSTRIA","award":["306394\/2021-9"],"award-info":[{"award-number":["306394\/2021-9"]}]},{"name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)","award":["055\/2023"],"award-info":[{"award-number":["055\/2023"]}]},{"name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)","award":["306394\/2021-9"],"award-info":[{"award-number":["306394\/2021-9"]}]},{"name":"Helmholtz-Zentrum Dresden-Rossendorf","award":["055\/2023"],"award-info":[{"award-number":["055\/2023"]}]},{"name":"Helmholtz-Zentrum Dresden-Rossendorf","award":["306394\/2021-9"],"award-info":[{"award-number":["306394\/2021-9"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Conveyor belts serve as the primary mode of ore transportation in mineral processing plants. Feeders, comprised of shorter conveyors, regulate the material flow from silos to longer conveyor belts by adjusting their velocity. This velocity manipulation is facilitated by automatic controllers that gauge the material weight on the conveyor using scales. However, due to positioning constraints of these scales, a notable delay ensues between measurement and the adjustment of the feeder speed. This dead time poses a significant challenge in control design, aiming to prevent oscillations in material levels on the conveyor belt. This paper contributes in two key areas: firstly, through a simulation-based comparison of various control techniques addressing this issue across diverse scenarios; secondly, by implementing the Smith predictor solution in an operational plant and contrasting its performance with that of a single PID controller. Evaluation spans both the transient flow rate during step change setpoints and a month-long assessment. The experimental results reveal a notable increase in production by 355 t\/h and a substantial reduction in flow rate oscillations on the conveyor belt, evidenced by a 55% decrease in the standard deviation.<\/jats:p>","DOI":"10.3390\/s24123870","type":"journal-article","created":{"date-parts":[[2024,6,14]],"date-time":"2024-06-14T10:42:34Z","timestamp":1718361754000},"page":"3870","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Delay Compensation in a Feeder\u2013Conveyor System Using the Smith Predictor: A Case Study in an Iron Ore Processing Plant"],"prefix":"10.3390","volume":"24","author":[{"given":"Tiago A.","family":"Moraes","sequence":"first","affiliation":[{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Instrumenta\u00e7\u00e3o, Controle e Automa\u00e7\u00e3o de Processos de Minera\u00e7\u00e3o, Universidade Federal de Ouro Preto e Instituto Tecnol\u00f3gico Vale, Ouro Preto 35400-000, MG, Brazil"},{"name":"Vale S.A., Cana\u00e3 dos Caraj\u00e1s 68537-000, PA, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8405-3518","authenticated-orcid":false,"given":"Mois\u00e9s T.","family":"da Silva","sequence":"additional","affiliation":[{"name":"Unidade Acad\u00eamica de Belo Jardim, Universidade Federal Rural de Pernambuco, Belo Jardim 55150-000, PE, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2974-8621","authenticated-orcid":false,"given":"Thiago A. M.","family":"Euz\u00e9bio","sequence":"additional","affiliation":[{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Instrumenta\u00e7\u00e3o, Controle e Automa\u00e7\u00e3o de Processos de Minera\u00e7\u00e3o, Universidade Federal de Ouro Preto e Instituto Tecnol\u00f3gico Vale, Ouro Preto 35400-000, MG, Brazil"},{"name":"Helmholtz-Zentrum Dresden-Rossendorf, Institute of Fluid Dynamics, 01328 Dresden, Germany"},{"name":"Virtus-CC, Campina Grande 58429-900, PB, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Wills, B.A., and Finch, J. (2015). 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