{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T19:22:48Z","timestamp":1790104968971,"version":"4.0.1"},"reference-count":47,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T00:00:00Z","timestamp":1768176000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2024YFB3814100"],"award-info":[{"award-number":["2024YFB3814100"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["62471454"],"award-info":[{"award-number":["62471454"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Project of Chongqing Science and Technology Bureau","award":["CSTB2025TIAD-KPX0097"],"award-info":[{"award-number":["CSTB2025TIAD-KPX0097"]}]},{"name":"Project of Chongqing Science and Technology Bureau","award":["CSTB2023TIAD-STX0037"],"award-info":[{"award-number":["CSTB2023TIAD-STX0037"]}]},{"name":"Shenzhen Science and Technology Program","award":["KJZD20240903100700001"],"award-info":[{"award-number":["KJZD20240903100700001"]}]},{"name":"Project of Chongqing Economic and Information Commission","award":["YJX-2025001001007"],"award-info":[{"award-number":["YJX-2025001001007"]}]},{"name":"Open Fund Project of National and Local Co-build Humanoid Robot Innovation Center","award":["HRCPUR20251106006"],"award-info":[{"award-number":["HRCPUR20251106006"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomimetics"],"abstract":"<jats:p>Humans could sensitively perceive and identify objects through dense mechanoreceptors distributed on the skin of curved fingertips. Inspired by this biological structure, this study presents a general conformal integration method for flexible tactile sensors on curved fingertip surfaces. By adopting a spherical partition design and an inverse mode auxiliary layering process, it ensures the uniform distribution of stress at different curvatures. The sensor adopts a 3 \u00d7 3 tactile array configuration, replicating the 3D curved surface distribution of human mechanoreceptors. By analyzing multi-point outputs, the sensor reconstructs contact pressure gradients and infers the softness or stiffness of touched objects, thereby realizing both structural and functional bionics. These sensors exhibit excellent linearity within 0\u2013100 kPa (sensitivity \u2248 36.86 kPa\u22121), fast response (2 ms), and outstanding durability (signal decay of only 1.94% after 30,000 cycles). It is worth noting that this conformal tactile fingertip integration method not only exhibits uniform responses at each unit, but also has the preload-free advantage, and then performs well in pulse detection and hardness discrimination. This work provides a novel bioinspired pathway for conformal integration of tactile sensors, enabling artificial skins and robotic fingertips with human-like tactile perception.<\/jats:p>","DOI":"10.3390\/biomimetics11010064","type":"journal-article","created":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T12:44:44Z","timestamp":1768221884000},"page":"64","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Preload-Free Conformal Integration of Tactile Sensors on the Fingertip\u2019s Curved Surface"],"prefix":"10.3390","volume":"11","author":[{"given":"Lei","family":"Liu","sequence":"first","affiliation":[{"name":"Department of Biomedical Engineering, School of Life Health Information Science and Engineering, Chongqing University of Posts and Telecommunications, Chongqing 400065, China"},{"name":"Chongqing Key Laboratory of Generic Technology and System of Service Robots, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peng","family":"Ran","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, School of Life Health Information Science and Engineering, Chongqing University of Posts and Telecommunications, Chongqing 400065, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yongyao","family":"Li","sequence":"additional","affiliation":[{"name":"National and Local Co-Build Humanoid Robot Innovation Center, Shanghai 201203, China"},{"name":"Humanoid Robot (Shanghai) Co., Ltd., Shanghai 201203, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tian","family":"Tang","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Generic Technology and System of Service Robots, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yun","family":"Hu","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Generic Technology and System of Service Robots, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jian","family":"Xiao","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Generic Technology and System of Service Robots, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daijian","family":"Luo","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Generic Technology and System of Service Robots, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lu","family":"Dai","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Generic Technology and System of Service Robots, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yufei","family":"Liu","sequence":"additional","affiliation":[{"name":"National and Local Co-Build Humanoid Robot Innovation Center, Shanghai 201203, China"},{"name":"Humanoid Robot (Shanghai) Co., Ltd., Shanghai 201203, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiahu","family":"Yuan","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Generic Technology and System of Service Robots, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3575-617X","authenticated-orcid":false,"given":"Dapeng","family":"Wei","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, School of Life Health Information Science and Engineering, Chongqing University of Posts and Telecommunications, Chongqing 400065, China"},{"name":"Chongqing Key Laboratory of Generic Technology and System of Service Robots, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"452","DOI":"10.1016\/j.mattod.2025.03.031","article-title":"The structure, material and performance of multi-functional tactile sensor and its application in robot field: A review","volume":"86","author":"Liang","year":"2025","journal-title":"Mater. 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