{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T14:59:12Z","timestamp":1781881152886,"version":"3.54.5"},"reference-count":32,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T00:00:00Z","timestamp":1781827200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The integration of olfactory feedback into Virtual Reality (VR) applications remains significantly underexplored compared with other sensory modalities, particularly within room-scale Cave Automatic Virtual Environments (CAVEs), where related research is even more limited. To address this gap, this paper presents Scentree, a custom olfactory system capable of delivering scents in real time based on user interactions, along with Smelling Ancient Greece, an olfactory-enhanced VR experience developed for integration within our CAVE system. Central to the proposed approach is the concept of the Diegetic Olfactory Feedback Loop, which reframes olfaction from a passive ambient effect into an active, interaction-driven feedback mechanism embedded within the narrative context of the virtual environment. To evaluate the system, we conducted a technical performance assessment and an exploratory user study (N=51) examining participant perceptions of immersion, presence, perceived realism, usability, and overall user experience. The findings support the feasibility of interaction-driven olfactory feedback as a multisensory design approach for CAVE environments and provide a foundation for future controlled investigations of olfactory feedback in immersive VR.<\/jats:p>","DOI":"10.3390\/s26123910","type":"journal-article","created":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T14:37:42Z","timestamp":1781879862000},"page":"3910","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Enhancing Multisensory Experience in CAVE Virtual Reality Through Olfactory Sensing"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-9695-8916","authenticated-orcid":false,"given":"Vasilis","family":"Vasileiadis","sequence":"first","affiliation":[{"name":"HCI-VR Lab, University of the Peloponnese, 22131 Tripoli, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0143-4228","authenticated-orcid":false,"given":"Anastasios","family":"Theodoropoulos","sequence":"additional","affiliation":[{"name":"HCI-VR Lab, University of the Peloponnese, 22131 Tripoli, Greece"},{"name":"Department of Performing and Digital Arts, University of the Peloponnese, 21100 Nafplio, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6094-3308","authenticated-orcid":false,"given":"George","family":"Lepouras","sequence":"additional","affiliation":[{"name":"HCI-VR Lab, University of the Peloponnese, 22131 Tripoli, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1007\/s13347-024-00707-1","article-title":"Immersive experience and virtual reality","volume":"37","year":"2024","journal-title":"Philos. 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