{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:02:13Z","timestamp":1760230933780,"version":"build-2065373602"},"reference-count":17,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2022,8,22]],"date-time":"2022-08-22T00:00:00Z","timestamp":1661126400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002241","name":"JST CREST","doi-asserted-by":"publisher","award":["JPMJCR20D5","JPMJPR18J1"],"award-info":[{"award-number":["JPMJCR20D5","JPMJPR18J1"]}],"id":[{"id":"10.13039\/501100002241","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002241","name":"Japan and JST PREST","doi-asserted-by":"publisher","award":["JPMJCR20D5","JPMJPR18J1"],"award-info":[{"award-number":["JPMJCR20D5","JPMJPR18J1"]}],"id":[{"id":"10.13039\/501100002241","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This study proposes a visual sensing system to investigate the self-propelled motions of droplets. In the visual sensing of self-propelled droplets, large field-of-view and high-resolution images are both required to investigate the behaviors of multiple droplets as well as chemical reactions in the droplets. Therefore, we developed a view-expansive microscope system using a color camera head to investigate these chemical reactions; in the system, we implemented an image processing algorithm to detect the behaviors of droplets over a large field of view. We conducted motion tracking and color identification experiments on the self-propelled droplets to verify the effectiveness of the proposed system. The experimental results demonstrate that the proposed system is able to detect the location and color of each self-propelled droplet in a large-area image.<\/jats:p>","DOI":"10.3390\/s22166309","type":"journal-article","created":{"date-parts":[[2022,8,22]],"date-time":"2022-08-22T23:49:56Z","timestamp":1661212196000},"page":"6309","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Visual Sensing System to Investigate Self-Propelled Motion and Internal Color of Multiple Aqueous Droplets"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7860-0725","authenticated-orcid":false,"given":"Tadayoshi","family":"Aoyama","sequence":"first","affiliation":[{"name":"Department of Micro-Nano Mechanical Science and Engineering, Nagoya University, Nagoya 464-8601, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shoki","family":"Yamada","sequence":"additional","affiliation":[{"name":"Department of Micro-Nano Mechanical Science and Engineering, Nagoya University, Nagoya 464-8601, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5860-4147","authenticated-orcid":false,"given":"Nobuhiko J.","family":"Suematsu","sequence":"additional","affiliation":[{"name":"School of Interdisciplenaly Mathematical Sciences and Meiji Institute for Advanced Study of Mathemtical Sciences (MIMS), Meiji University, Tokyo 101-8301, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9304-4667","authenticated-orcid":false,"given":"Masaru","family":"Takeuchi","sequence":"additional","affiliation":[{"name":"Department of Micro-Nano Mechanical Science and Engineering, Nagoya University, Nagoya 464-8601, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9917-098X","authenticated-orcid":false,"given":"Yasuhisa","family":"Hasegawa","sequence":"additional","affiliation":[{"name":"Department of Micro-Nano Mechanical Science and Engineering, Nagoya University, Nagoya 464-8601, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"13424","DOI":"10.1021\/ja047697z","article-title":"Catalytic Nanomotors: Autonomous Movement of Striped Nanorods","volume":"124","author":"Paxton","year":"2004","journal-title":"J. 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