{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:13:37Z","timestamp":1792790017065,"version":"4.5.0"},"reference-count":42,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T00:00:00Z","timestamp":1790726400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Medicine, Pharmacy, Science and Technology \u201cGeorge Emil Palade\u201d of T\u00e2rgu Mure\u0219","award":["163\/1\/10.01.2023"],"award-info":[{"award-number":["163\/1\/10.01.2023"]}]},{"award":["163\/1\/10.01.2023"],"award-info":[{"award-number":["163\/1\/10.01.2023"]}],"id":[{"id":"https:\/\/ror.org\/03gwbzf29","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Technical University of Cluj-Napoca","id":[{"id":"https:\/\/ror.org\/03r8nwp71","id-type":"ROR","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/03r8nwp71","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Supervisory monitoring and control systems require prompt access to process data and information. The systems described in the literature utilize Mixed Reality (MR) technology and have different system architectures and communication methods. Some systems require the presence of intermediary elements for data exchange between the MR environment and the industrial control system. In this article, we suggest and develop an MR-based system for the supervisory monitoring and control of an industrial assembly line. The uniqueness of the suggested system consists of bidirectional communication between the MR system and the main PLC using the OPC UA protocol without intermediary elements in the MR\u2013PLC communication chain. The Modbus TCP protocol is used for obtaining parameters from the network analyzer. The system allows us to monitor some process parameters and sensors on the assembly line and transfer supervisory commands from the MR interface to the main PLC using virtual controls on physical elements. The system was built using the MRTK library inside the Unity environment. To experimentally evaluate the system, experiments were conducted on the industrial assembly line, where the process parameters and communication performance were recorded under experimental conditions.<\/jats:p>","DOI":"10.3390\/s26196208","type":"journal-article","created":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T13:01:19Z","timestamp":1790773279000},"page":"6208","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Mixed Reality-Based Monitoring and Supervisory Control of an Industrial Assembly Line Using Direct OPC UA and Modbus TCP Communication"],"prefix":"10.3390","volume":"26","author":[{"given":"Tudor","family":"Covrig","sequence":"first","affiliation":[{"name":"Automation Department, Technical University of Cluj-Napoca, 400027 Cluj-Napoca, Romania"},{"name":"Department of Electrical Engineering and Computers, University of Medicine, Pharmacy, Sciences and Technology of T\u00e2rgu Mures, 540088 T\u00e2rgu Mures, Romania"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"}]},{"given":"Adrian","family":"Duka","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Computers, University of Medicine, Pharmacy, Sciences and Technology of T\u00e2rgu Mures, 540088 T\u00e2rgu Mures, Romania"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3377-7898","authenticated-orcid":false,"given":"Liviu","family":"Miclea","sequence":"additional","affiliation":[{"name":"Automation Department, Technical University of Cluj-Napoca, 400027 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"107241","DOI":"10.1016\/j.cie.2021.107241","article-title":"Industry 4.0 reference architectures: State of the art and future trends","volume":"156","author":"Nakagawa","year":"2021","journal-title":"Comput. 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