{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T14:20:06Z","timestamp":1783347606031,"version":"3.54.6"},"reference-count":40,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T00:00:00Z","timestamp":1783296000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Robot. AI"],"abstract":"<jats:p>The assessment of tissue properties via direct palpation is essential for localizing abnormalities during surgery. However, Minimally Invasive Surgery (MIS) eliminates this tactile feedback, creating a critical sensory gap. To address this, the EU Horizon project PALPABLE is developing novel fiber-optic sensing modalities for stiffness assessment. Successful integration of this technology requires an articulation interface that balances high maneuverability with the structural stability necessary for deflection-free tissue palpation. We present a single-degree-of-freedom (DOF) soft silicone actuator integrated with a modular, bioinspired passive stiffening element. Mechanical loading tests, motion tracking, and Finite Element Method (FEM)-guided design iterations validate the stiffening strategy and actuator performance. The design achieves a substantial increase in bending stiffness, improving the stiffness\u2013pressure response by 8-fold relative to the unstiffened actuator under critical loading (normal force at a 90\u00b0 bend). Furthermore, we developed a compact, custom pneumatic syringe pump with closed-loop pressure control to ensure precise, safe operation in surgical environments. By combining embedded fiber-optic sensing with machine-learning models, the system achieves free-space full-shape reconstruction with approximately 1% error. This work delivers a compact, load-capable, and sensorized soft actuator tailored for PALPABLE\u2019s probe manipulation requirements, enabling safe, controllable, and data-rich tissue palpation in confined anatomical spaces.<\/jats:p>","DOI":"10.3389\/frobt.2026.1832079","type":"journal-article","created":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T13:20:23Z","timestamp":1783344023000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["PALPABLE: enhanced bending stiffness and proprioception in soft actuators for laparoscopic palpation"],"prefix":"10.3389","volume":"13","author":[{"given":"Christos Vasileios","family":"Lousis","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, School of Engineering, Control Systems and Robotics Laboratory (CSRL), Hellenic Mediterranean University","place":["Heraklion, Greece"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Myrto","family":"Inglezou","sequence":"additional","affiliation":[{"name":"AI Innovation Center, University of Essex","place":["Colchester, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilias","family":"Zournatzis","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, School of Engineering, Control Systems and Robotics Laboratory (CSRL), Hellenic Mediterranean University","place":["Heraklion, Greece"]},{"name":"Bendabl SMPC","place":["Athens, Greece"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Georgios","family":"Violakis","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, School of Engineering, Control Systems and Robotics Laboratory (CSRL), Hellenic Mediterranean University","place":["Heraklion, Greece"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Panagiotis","family":"Polygerinos","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, School of Engineering, Control Systems and Robotics Laboratory (CSRL), Hellenic Mediterranean University","place":["Heraklion, Greece"]},{"name":"Department of Industrial Design and Production Engineering, School of Engineering, University of West Attica","place":["Athens, Greece"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,7,6]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"102224","DOI":"10.1016\/j.xcrp.2024.102224","article-title":"Shape reconstruction of soft continuum robots via the fusion of local strains and global poses","volume":"5","author":"An","year":"2024","journal-title":"Cell. 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