{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T09:07:19Z","timestamp":1788858439852,"version":"build-2803163510"},"reference-count":29,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T00:00:00Z","timestamp":1788307200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Reliable tactile object shape recognition on robotic hands is often achieved using dense sensor arrays or vision-based tactile skins, which increase fabrication complexity and computational cost. This work demonstrates that high-recognition performance can instead be achieved through principled sparse sensing. A minimal multimodal tactile system is developed by fusing soft capacitive stretch sensors at the proximal interphalangeal and metacarpophalangeal joints of the fingers with a sparse six-element palmar pressure array, integrated into a human-like hand mechanically constrained to emulate robotic grasping under a controlled and repeatable protocol. Using an ANOVA-based channel selection, low-informative metacarpophalangeal signals are identified and removed, reducing the number of sensors at the finger joints while improving classification accuracy. A lightweight multi-layer perceptron operating on this low-dimensional input achieves 95.4% size-invariant recognition accuracy across 12 rigid objects representing four geometric primitives\u2014cuboid, sphere, cylinder, and cone\u2014outperforming the denser baseline. Ablation studies confirm the complementary roles of finger-joint deformation, which encodes curvature cues, and palmar force distribution, which captures contact topology; neither modality alone achieves comparable performance. Beyond accuracy, the proposed design reduces sensor count, wiring, and computational requirements, enabling embedded-ready deployment. The results show that data-driven sensor placement, rather than sensors at all finger joints, can yield sufficient grasp-based shape recognition, offering practical guidance for tactile perception in resource-constrained robotic hands.<\/jats:p>","DOI":"10.3390\/s26175583","type":"journal-article","created":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T14:35:29Z","timestamp":1788359729000},"page":"5583","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Object Shape Recognition Using Sparse Soft Capacitive Tactile Sensors for Robotic Hands"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-0106-0016","authenticated-orcid":false,"given":"Xinmeng","family":"Ding","sequence":"first","affiliation":[{"name":"Department of Mechanical and Mechatronics Engineering, University of Auckland, Auckland 1010, New Zealand"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4955-2733","authenticated-orcid":false,"given":"Yuting","family":"Zhu","sequence":"additional","affiliation":[{"name":"School of Engineering and Built Environment, Griffith University, Nathan, QLD 4111, Australia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"}]},{"given":"Mengdi","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Textiles, Donghua University, Shanghai 201620, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"conceptualization","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8157-8995","authenticated-orcid":false,"given":"Wee Chen","family":"Gan","sequence":"additional","affiliation":[{"name":"School of Energy and Chemical Engineering, Xiamen University Malaysia, Sepang 43900, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"conceptualization","vocabulary":"credit"}]},{"given":"Shaohua","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Mechatronics Engineering, University of Auckland, Auckland 1010, New Zealand"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"software","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9308-508X","authenticated-orcid":false,"given":"Kean","family":"Aw","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Mechatronics Engineering, University of Auckland, Auckland 1010, New Zealand"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4121","DOI":"10.1109\/JSEN.2013.2279056","article-title":"Directions toward effective utilization of tactile skin: A review","volume":"13","author":"Dahiya","year":"2013","journal-title":"IEEE Sens. 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