{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T16:35:10Z","timestamp":1777653310653,"version":"3.51.4"},"reference-count":43,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,5,30]],"date-time":"2022-05-30T00:00:00Z","timestamp":1653868800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Key Area Research and Development Program of Guangdong Province","award":["2020B0101130012"],"award-info":[{"award-number":["2020B0101130012"]}]},{"name":"The Key Area Research and Development Program of Guangdong Province","award":["FS0AA-KJ919-4402-0060"],"award-info":[{"award-number":["FS0AA-KJ919-4402-0060"]}]},{"name":"The Foshan Science and Technology Innovation Team Project","award":["2020B0101130012"],"award-info":[{"award-number":["2020B0101130012"]}]},{"name":"The Foshan Science and Technology Innovation Team Project","award":["FS0AA-KJ919-4402-0060"],"award-info":[{"award-number":["FS0AA-KJ919-4402-0060"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>High-precision indoor localization is growing extremely quickly, especially for multi-floor scenarios. The data on existing indoor positioning schemes, mainly, come from wireless, visual, or lidar means, which are limited to a single sensor. With the massive deployment of WiFi access points and low-cost cameras, it is possible to combine the above three methods to achieve more accurate, complete, and reliable location results. However, the existing SLAM rapidly advances, so hybrid visual and wireless approaches take advantage of this, in a straightforward manner, without exploring their interactions. In this paper, a high-precision multi-floor indoor positioning method, based on vision, wireless signal characteristics, and lidar is proposed. In the joint scheme, we, first, use the positioning data output in lidar SLAM as the theoretical reference position for visual images; then, use a WiFi signal to estimate the rough area, with likelihood probability; and, finally, use the visual image to fine-tune the floor-estimation and location results. Based on the numerical results, we show that the proposed joint localization scheme can achieve 0.62 m of 3D localization accuracy, on average, and a 1.24-m MSE for two-dimensional tracking trajectories, with an estimation accuracy for the floor equal to 89.22%. Meanwhile, the localization process takes less than 0.25 s, which is of great importance for practical implementation.<\/jats:p>","DOI":"10.3390\/s22114162","type":"journal-article","created":{"date-parts":[[2022,5,31]],"date-time":"2022-05-31T02:30:06Z","timestamp":1653964206000},"page":"4162","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Multi-Floor Indoor Localization Based on Multi-Modal Sensors"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3263-7298","authenticated-orcid":false,"given":"Guangbing","family":"Zhou","sequence":"first","affiliation":[{"name":"School of Information and Communication Engineering, Shanghai University, Shanghai 200444, China"},{"name":"Institute of Intelligent Manufacturing, Guangdong Academy of Sciences, Guangzhou 510070, China"},{"name":"South China Robotics Innovation Research Institute, Foshan 528300, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shugong","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Information and Communication Engineering, Shanghai University, Shanghai 200444, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5156-9235","authenticated-orcid":false,"given":"Shunqing","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Information and Communication Engineering, Shanghai University, Shanghai 200444, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yu","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Information and Communication Engineering, Shanghai University, Shanghai 200444, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1055-6267","authenticated-orcid":false,"given":"Chenlu","family":"Xiang","sequence":"additional","affiliation":[{"name":"School of Information and Communication Engineering, Shanghai University, Shanghai 200444, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1080\/17489725.2018.1508763","article-title":"Location based services: Ongoing evolution and research agenda","volume":"12","author":"Huang","year":"2018","journal-title":"J. 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