{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T20:19:58Z","timestamp":1782937198566,"version":"3.54.5"},"reference-count":38,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,4,28]],"date-time":"2021-04-28T00:00:00Z","timestamp":1619568000000},"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>In recent years, we have assisted with an impressive advance in augmented reality systems and computer vision algorithms, based on image processing and artificial intelligence. Thanks to these technologies, mainstream smartphones are able to estimate their own motion in 3D space with high accuracy. In this paper, we exploit such technologies to support the autonomous mobility of people with visual disabilities, identifying pre-defined virtual paths and providing context information, reducing the distance between the digital and real worlds. In particular, we present ARIANNA+, an extension of ARIANNA, a system explicitly designed for visually impaired people for indoor and outdoor localization and navigation. While ARIANNA is based on the assumption that landmarks, such as QR codes, and physical paths (composed of colored tapes, painted lines, or tactile pavings) are deployed in the environment and recognized by the camera of a common smartphone, ARIANNA+ eliminates the need for any physical support thanks to the ARKit library, which we exploit to build a completely virtual path. Moreover, ARIANNA+ adds the possibility for the users to have enhanced interactions with the surrounding environment, through convolutional neural networks (CNNs) trained to recognize objects or buildings and enabling the possibility of accessing contents associated with them. By using a common smartphone as a mediation instrument with the environment, ARIANNA+ leverages augmented reality and machine learning for enhancing physical accessibility. The proposed system allows visually impaired people to easily navigate in indoor and outdoor scenarios simply by loading a previously recorded virtual path and providing automatic guidance along the route, through haptic, speech, and sound feedback.<\/jats:p>","DOI":"10.3390\/s21093061","type":"journal-article","created":{"date-parts":[[2021,4,28]],"date-time":"2021-04-28T22:29:07Z","timestamp":1619648947000},"page":"3061","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":63,"title":["A Navigation and Augmented Reality System for Visually Impaired People"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1359-1607","authenticated-orcid":false,"given":"Alice","family":"Lo Valvo","sequence":"first","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 di Palermo, Viale delle Scienze, Ed. 9, 90128 Palermo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7663-4702","authenticated-orcid":false,"given":"Daniele","family":"Croce","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 di Palermo, Viale delle Scienze, Ed. 9, 90128 Palermo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6256-2752","authenticated-orcid":false,"given":"Domenico","family":"Garlisi","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 di Palermo, Viale delle Scienze, Ed. 9, 90128 Palermo, Italy"},{"name":"Consorzio Nazionale Interuniversitario delle Telecomunicazioni, Viale G.P. Usberti, 181\/A, 43124 Parma, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5784-6902","authenticated-orcid":false,"given":"Fabrizio","family":"Giuliano","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 di Palermo, Viale delle Scienze, Ed. 9, 90128 Palermo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2304-4394","authenticated-orcid":false,"given":"Laura","family":"Giarr\u00e9","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria \u201cEnzo Ferrari\u201d, Universit\u00e0 di Modena e Reggio Emilia, Via P. Vivarelli, 10, 41125 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1305-0248","authenticated-orcid":false,"given":"Ilenia","family":"Tinnirello","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 di Palermo, Viale delle Scienze, Ed. 9, 90128 Palermo, Italy"},{"name":"Consorzio Nazionale Interuniversitario delle Telecomunicazioni, Viale G.P. Usberti, 181\/A, 43124 Parma, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,28]]},"reference":[{"key":"ref_1","unstructured":"Bahl, P., and Padmanabhan, V.N. (2000, January 26\u201330). RADAR: An in-building RF-based user location and tracking system. Proceedings of the IEEE INFOCOM 2000, Conference on Computer Communications, Nineteenth Annual Joint Conference of the IEEE Computer and Communications Societies (Cat. 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