{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,20]],"date-time":"2026-06-20T17:00:56Z","timestamp":1781974856085,"version":"3.54.5"},"reference-count":34,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2021,8,9]],"date-time":"2021-08-09T00:00:00Z","timestamp":1628467200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["61903317"],"award-info":[{"award-number":["61903317"]}]},{"name":"National Key R&amp;D Program of China","award":["2019YFB1310403"],"award-info":[{"award-number":["2019YFB1310403"]}]},{"name":"Shenzhen Institute of Artificial Intelligence and Robotics for Society","award":["AC01202101011"],"award-info":[{"award-number":["AC01202101011"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Recent achievements in the field of computer vision, reinforcement learning, and locomotion control have largely extended legged robots\u2019 maneuverability in complex natural environments. However, little research focuses on sensing and analyzing the physical properties of the ground, which is crucial to robots\u2019 locomotion during their interaction with highly irregular profiles, deformable terrains, and slippery surfaces. A biomimetic, flexible, multimodal sole sensor (FMSS) designed for legged robots to identify the ontological status and ground information, such as reaction force mapping, contact situation, terrain, and texture information, to achieve agile maneuvers was innovatively presented in this paper. The FMSS is flexible and large-loaded (20 Pa\u2013800 kPa), designed by integrating a triboelectric sensing coat, embedded piezoelectric sensor, and piezoresistive sensor array. To evaluate the effectiveness and adaptability in different environments, the multimodal sensor was mounted on one of the quadruped robot\u2019s feet and one of the human feet then traversed through different environments in real-world tests. The experiment\u2019s results demonstrated that the FMSS could recognize terrain, texture, hardness, and contact conditions during locomotion effectively and retrain its sensitivity (0.66 kPa\u22121), robustness, and compliance. The presented work indicates the FMSS\u2019s potential to extend the feasibility and dexterity of tactile perception for state estimation and complex scenario detection.<\/jats:p>","DOI":"10.3390\/s21165359","type":"journal-article","created":{"date-parts":[[2021,8,9]],"date-time":"2021-08-09T05:17:06Z","timestamp":1628486226000},"page":"5359","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["A Flexible Multimodal Sole Sensor for Legged Robot Sensing Complex Ground Information during Locomotion"],"prefix":"10.3390","volume":"21","author":[{"given":"Yingtian","family":"Xu","sequence":"first","affiliation":[{"name":"Shenzhen Institute of Artificial Intelligence and Robotics for Society (AIRS), Shenzhen 518129, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9582-8139","authenticated-orcid":false,"given":"Ziya","family":"Wang","sequence":"additional","affiliation":[{"name":"Shenzhen Institute of Artificial Intelligence and Robotics for Society (AIRS), Shenzhen 518129, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wanjun","family":"Hao","sequence":"additional","affiliation":[{"name":"Shenzhen Institute of Artificial Intelligence and Robotics for Society (AIRS), Shenzhen 518129, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenyu","family":"Zhao","sequence":"additional","affiliation":[{"name":"Shenzhen Institute of Artificial Intelligence and Robotics for Society (AIRS), Shenzhen 518129, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Waner","family":"Lin","sequence":"additional","affiliation":[{"name":"Shenzhen Institute of Artificial Intelligence and Robotics for Society (AIRS), Shenzhen 518129, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bingchen","family":"Jin","sequence":"additional","affiliation":[{"name":"Shenzhen Institute of Artificial Intelligence and Robotics for Society (AIRS), Shenzhen 518129, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ning","family":"Ding","sequence":"additional","affiliation":[{"name":"Shenzhen Institute of Artificial Intelligence and Robotics for Society (AIRS), Shenzhen 518129, China"},{"name":"Institute of Robotics and Intelligent Manufacturing, The Chinese University of Hong Kong, Shenzhen 518172, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1109\/JAS.2018.7511258","article-title":"A study on development of a hybrid aerial\/terrestrial robot system for avoiding ground obstacles by flight","volume":"6","author":"Premachandra","year":"2018","journal-title":"IEEE\/CAA J. 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