{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,7]],"date-time":"2026-03-07T18:29:53Z","timestamp":1772908193589,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,5,8]],"date-time":"2023-05-08T00:00:00Z","timestamp":1683504000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002241","name":"Japan Science and Technology Agency","doi-asserted-by":"publisher","award":["JPMJMI21H4"],"award-info":[{"award-number":["JPMJMI21H4"]}],"id":[{"id":"10.13039\/501100002241","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002241","name":"Japan Science and Technology Agency","doi-asserted-by":"publisher","award":["JP1190410"],"award-info":[{"award-number":["JP1190410"]}],"id":[{"id":"10.13039\/501100002241","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002241","name":"Japan Science and Technology Agency","doi-asserted-by":"publisher","award":["JP982714"],"award-info":[{"award-number":["JP982714"]}],"id":[{"id":"10.13039\/501100002241","id-type":"DOI","asserted-by":"publisher"}]},{"name":"JSPS KAKENHI","award":["JPMJMI21H4"],"award-info":[{"award-number":["JPMJMI21H4"]}]},{"name":"JSPS KAKENHI","award":["JP1190410"],"award-info":[{"award-number":["JP1190410"]}]},{"name":"JSPS KAKENHI","award":["JP982714"],"award-info":[{"award-number":["JP982714"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Recent developments in robotics have enabled humanoid robots to be used in tasks where they have to physically interact with humans, including robot-supported caregiving. This interaction\u2014referred to as physical human\u2013robot interaction (pHRI)\u2014requires physical contact between the robot and the human body; one way to improve this is to use efficient sensing methods for the physical contact. In this paper, we use a flexible tactile sensing array and integrate it as a tactile skin for the humanoid robot HRP-4C. As the sensor can take any shape due to its flexible property, a particular focus is given on its spatial calibration, i.e., the determination of the locations of the sensor cells and their normals when attached to the robot. For this purpose, a novel method of spatial calibration using B-spline surfaces has been developed. We demonstrate with two methods that this calibration method gives a good approximation of the sensor position and show that our flexible tactile sensor can be fully integrated on a robot and used as input for robot control tasks. These contributions are a first step toward the use of flexible tactile sensors in pHRI applications.<\/jats:p>","DOI":"10.3390\/s23094569","type":"journal-article","created":{"date-parts":[[2023,5,9]],"date-time":"2023-05-09T01:34:26Z","timestamp":1683596066000},"page":"4569","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Spatial Calibration of Humanoid Robot Flexible Tactile Skin for Human\u2013Robot Interaction"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2931-1032","authenticated-orcid":false,"given":"S\u00e9lim","family":"Chefchaouni Moussaoui","sequence":"first","affiliation":[{"name":"National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8560, Japan"},{"name":"CNRS-AIST Joint Robotics Laboratory (JRL), AIST, Tsukuba 305-8560, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0850-070X","authenticated-orcid":false,"given":"Rafael","family":"Cisneros-Lim\u00f3n","sequence":"additional","affiliation":[{"name":"National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8560, Japan"},{"name":"CNRS-AIST Joint Robotics Laboratory (JRL), AIST, Tsukuba 305-8560, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8288-7973","authenticated-orcid":false,"given":"Hiroshi","family":"Kaminaga","sequence":"additional","affiliation":[{"name":"National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8560, Japan"},{"name":"CNRS-AIST Joint Robotics Laboratory (JRL), AIST, Tsukuba 305-8560, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7537-9498","authenticated-orcid":false,"given":"Mehdi","family":"Benallegue","sequence":"additional","affiliation":[{"name":"National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8560, Japan"},{"name":"CNRS-AIST Joint Robotics Laboratory (JRL), AIST, Tsukuba 305-8560, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4270-4722","authenticated-orcid":false,"given":"Taiki","family":"Nobeshima","sequence":"additional","affiliation":[{"name":"National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8560, Japan"},{"name":"Human Augmentation Research Center (HARC), AIST, Kashiwa 277-0882, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4076-9634","authenticated-orcid":false,"given":"Shusuke","family":"Kanazawa","sequence":"additional","affiliation":[{"name":"National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8560, Japan"},{"name":"Human Augmentation Research Center (HARC), AIST, Kashiwa 277-0882, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0277-3467","authenticated-orcid":false,"given":"Fumio","family":"Kanehiro","sequence":"additional","affiliation":[{"name":"National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8560, Japan"},{"name":"CNRS-AIST Joint Robotics Laboratory (JRL), AIST, Tsukuba 305-8560, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Arents, J., Abolins, V., Judvaitis, J., Vismanis, O., Oraby, A., and Ozols, K. 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