{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T14:42:06Z","timestamp":1780324926472,"version":"3.54.1"},"reference-count":50,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,14]],"date-time":"2022-01-14T00:00:00Z","timestamp":1642118400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Natural science research projects in Jiangsu Universities","award":["18KJA4600050"],"award-info":[{"award-number":["18KJA4600050"]}]},{"name":"Natural science research projects in Jiangsu Universities","award":["21KJB460010"],"award-info":[{"award-number":["21KJB460010"]}]},{"name":"High level talent project of &quot;six talent peaks&quot; in Jiangsu Province","award":["GDZB-024"],"award-info":[{"award-number":["GDZB-024"]}]},{"name":"Open project of National Key Laboratory of Robotics","award":["2018-016"],"award-info":[{"award-number":["2018-016"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["51305209"],"award-info":[{"award-number":["51305209"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Jiangsu Government Scholar for Overseas Studies","award":["JS-2016-62"],"award-info":[{"award-number":["JS-2016-62"]}]},{"name":"Youth science and technology innovation fund of Nanjing Forestry University","award":["CX2019009"],"award-info":[{"award-number":["CX2019009"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Flexible sensing tends to be widely exploited in the process of human\u2013computer interactions of intelligent robots for its contact compliance and environmental adaptability. A novel flexible capacitive tactile sensor was proposed for multi-directional force sensing, which is based on carbon black\/polydimethylsiloxane (PDMS) composite dielectric layer and upper and lower electrodes of carbon nanotubes\/polydimethylsiloxane (CNTs\/PDMS) composite layer. By changing the ratio of carbon black, the resolution of carbon black\/PDMS composite layer increases at 4 wt%, and then decreases, which was explained according to the percolation theory of the conductive particles in the polymer matrix. Mathematical model of force and capacitance variance was established, which can be used to predict the value of the applied force. Then, the prototype with carbon black\/PDMS composite dielectric layer was fabricated and characterized. SEM observation was conducted and a ratio was introduced in the composites material design. It was concluded that the resolution of carbon sensor can reach 0.1 N within 50 N in normal direction and 0.2 N in 0\u201310 N in tangential direction with good stability. Finally, the multi-directional force results were obtained. Compared with the individual directional force results, the output capacitance value of multi-directional force was lower, which indicated the amplitude decrease in capacity change in the normal and tangential direction. This might be caused by the deformation distribution in the normal and tangential direction under multi-directional force.<\/jats:p>","DOI":"10.3390\/s22020628","type":"journal-article","created":{"date-parts":[[2022,1,16]],"date-time":"2022-01-16T20:45:21Z","timestamp":1642365921000},"page":"628","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":62,"title":["Carbon Black\/PDMS Based Flexible Capacitive Tactile Sensor for Multi-Directional Force Sensing"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4574-3900","authenticated-orcid":false,"given":"Yinlong","family":"Zhu","sequence":"first","affiliation":[{"name":"College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China"},{"name":"State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110169, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xin","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kaimei","family":"Chu","sequence":"additional","affiliation":[{"name":"College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0680-6908","authenticated-orcid":false,"given":"Xu","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhiqiang","family":"Hu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110169, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3132-0213","authenticated-orcid":false,"given":"Haijun","family":"Su","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, Ohio State University, Columbus, OH 43210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"10104","DOI":"10.1021\/acsnano.0c03294","article-title":"Triode-mimicking graphene pressure sensor with positive resistance variation for physiology and motion monitoring","volume":"14","author":"Wu","year":"2020","journal-title":"ACS Nano"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1033","DOI":"10.1021\/acs.accounts.8b00015","article-title":"Skin-inspired electronics: An emerging paradigm","volume":"51","author":"Wang","year":"2018","journal-title":"Acc. 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