{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,25]],"date-time":"2026-02-25T12:01:38Z","timestamp":1772020898589,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,2,22]],"date-time":"2026-02-22T00:00:00Z","timestamp":1771718400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the National Key R&D Program of China","award":["2024YFB3213600"],"award-info":[{"award-number":["2024YFB3213600"]}]},{"name":"Shenzhen Science and Technology Program","award":["JCYJ20250604175514018"],"award-info":[{"award-number":["JCYJ20250604175514018"]}]},{"name":"Shenzhen Science and Technology Program","award":["JCYJ20241202123724032"],"award-info":[{"award-number":["JCYJ20241202123724032"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>High-resolution contact localization and three-axis force estimation are crucial for human\u2013robot interaction and precision manipulation, yet the sensing area is limited by channel density and wiring cost. Sparse strain readout makes joint estimation of location and three-axis force challenging due to cross-axis coupling and nonlinear responses, while dense arrays or extensive calibration increase complexity. We present a sparse strain-node tactile interface device (SSTID) whose three-module layout is optimized via particle swarm optimization to maximize informative response overlap, enabling contact localization (x,y) and three-axis force (Fx,Fy,Fz) estimation using only nine strain channels. We further propose a strain-node contact-state decoding framework (SCDF) implemented with a lightweight multilayer perceptron and trained via a two-stage sim-to-real strategy, including FEM pretraining followed by few-shot real-data adaptation. Experiments demonstrate accurate contact-state decoding with full-workspace characterization, supporting low-cost and scalable deployment of sparse tactile interfaces.<\/jats:p>","DOI":"10.3390\/s26041378","type":"journal-article","created":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T08:58:21Z","timestamp":1771837101000},"page":"1378","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["High-Resolution Contact Localization and Three-Axis Force Estimation with a Sparse Strain-Node Tactile Interface Device"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-9802-9473","authenticated-orcid":false,"given":"Yanyan","family":"Wu","sequence":"first","affiliation":[{"name":"School of Advanced Manufacturing, Sun Yat-sen University, Shenzhen 518005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hanhan","family":"Wu","sequence":"additional","affiliation":[{"name":"School of Advanced Manufacturing, Sun Yat-sen University, Shenzhen 518005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yifei","family":"Han","sequence":"additional","affiliation":[{"name":"School of Advanced Manufacturing, Sun Yat-sen University, Shenzhen 518005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yi","family":"Ding","sequence":"additional","affiliation":[{"name":"School of Advanced Manufacturing, Sun Yat-sen University, Shenzhen 518005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bosheng","family":"Cao","sequence":"additional","affiliation":[{"name":"School of Advanced Manufacturing, Sun Yat-sen University, Shenzhen 518005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5396-7643","authenticated-orcid":false,"given":"Chongkun","family":"Xia","sequence":"additional","affiliation":[{"name":"School of Advanced Manufacturing, Sun Yat-sen University, Shenzhen 518005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"eabd7795","DOI":"10.1126\/sciadv.abd7795","article-title":"Scalable tactile sensor arrays on flexible substrates with high spatiotemporal resolution enabling slip and grip for closed-loop robotics","volume":"6","author":"Oh","year":"2020","journal-title":"Sci. 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