{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,7]],"date-time":"2026-07-07T00:52:11Z","timestamp":1783385531395,"version":"3.54.6"},"reference-count":25,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2017,11,3]],"date-time":"2017-11-03T00:00:00Z","timestamp":1509667200000},"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 search and rescue activities, unmanned aerial vehicles (UAV) should exploit sound information to compensate for poor visual information. This paper describes the design and implementation of a UAV-embedded microphone array system for sound source localization in outdoor environments. Four critical development problems included water-resistance of the microphone array, efficiency in assembling, reliability of wireless communication, and sufficiency of visualization tools for operators. To solve these problems, we developed a spherical microphone array system (SMAS) consisting of a microphone array, a stable wireless network communication system, and intuitive visualization tools. The performance of SMAS was evaluated with simulated data and a demonstration in the field. Results confirmed that the SMAS provides highly accurate localization, water resistance, prompt assembly, stable wireless communication, and intuitive information for observers and operators.<\/jats:p>","DOI":"10.3390\/s17112535","type":"journal-article","created":{"date-parts":[[2017,11,3]],"date-time":"2017-11-03T12:39:20Z","timestamp":1509712760000},"page":"2535","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":117,"title":["Design of UAV-Embedded Microphone Array System for Sound Source Localization in Outdoor Environments"],"prefix":"10.3390","volume":"17","author":[{"given":"Kotaro","family":"Hoshiba","sequence":"first","affiliation":[{"name":"Department of Systems and Control Engineering, School of Engineering, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8552, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kai","family":"Washizaki","sequence":"additional","affiliation":[{"name":"Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mizuho","family":"Wakabayashi","sequence":"additional","affiliation":[{"name":"Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takahiro","family":"Ishiki","sequence":"additional","affiliation":[{"name":"Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4278-829X","authenticated-orcid":false,"given":"Makoto","family":"Kumon","sequence":"additional","affiliation":[{"name":"Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshiaki","family":"Bando","sequence":"additional","affiliation":[{"name":"Graduate School of Informatics, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"Gabriel","sequence":"additional","affiliation":[{"name":"Department of Systems and Control Engineering, School of Engineering, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8552, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kazuhiro","family":"Nakadai","sequence":"additional","affiliation":[{"name":"Department of Systems and Control Engineering, School of Engineering, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8552, Japan"},{"name":"Honda Research Institute Japan Co., Ltd., 8-1 Honcho, Wako, Saitama 351-0188, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8704-4318","authenticated-orcid":false,"given":"Hiroshi","family":"Okuno","sequence":"additional","affiliation":[{"name":"Graduate Program for Embodiment Informatics, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,11,3]]},"reference":[{"key":"ref_1","unstructured":"Nakadai, K., Lourens, T., Okuno, H.G., and Kitano, H. 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