{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,3]],"date-time":"2026-05-03T03:36:49Z","timestamp":1777779409436,"version":"3.51.4"},"reference-count":42,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2022,10,11]],"date-time":"2022-10-11T00:00:00Z","timestamp":1665446400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Guangdong Science and Technology Research Council","award":["2020B1515120064"],"award-info":[{"award-number":["2020B1515120064"]}]},{"name":"Guangdong Science and Technology Research Council","award":["ITS\/156\/20FP"],"award-info":[{"award-number":["ITS\/156\/20FP"]}]},{"name":"Innovation and Technology Fund, HKSAR","award":["2020B1515120064"],"award-info":[{"award-number":["2020B1515120064"]}]},{"name":"Innovation and Technology Fund, HKSAR","award":["ITS\/156\/20FP"],"award-info":[{"award-number":["ITS\/156\/20FP"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Soft robots can create complicated structures and functions for rehabilitation. The posture perception of soft actuators is critical for performing closed-loop control for a precise location. It is essential to have a sensor with both soft and flexible characteristics that does not affect the movement of a soft actuator. This paper presents a novel end-to-end posture perception method that employs flexible sensors with kirigami-inspired structures and long short-term memory (LSTM) neural networks. The sensors were developed with conductive sponge materials. With one-step calibration from the sensor output, the posture of the soft actuator could be calculated by the LSTM network. The method was validated by attaching the developed sensors to a soft fiber-reinforced bending actuator. The results showed the accuracy of posture prediction of sponge sensors with three kirigami-inspired structures ranged from 0.91 to 0.97 in terms of R2. The sponge sensors only generated a resistive torque value of 0.96 mNm at the maximum bending position when attached to a soft actuator, which would minimize the effect on actuator movement. The kirigami-inspired flexible sponge sensor could in future enhance soft robotic development.<\/jats:p>","DOI":"10.3390\/s22207705","type":"journal-article","created":{"date-parts":[[2022,10,12]],"date-time":"2022-10-12T02:10:27Z","timestamp":1665540627000},"page":"7705","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Soft Robots\u2019 Dynamic Posture Perception Using Kirigami-Inspired Flexible Sensors with Porous Structures and Long Short-Term Memory (LSTM) Neural Networks"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9475-8677","authenticated-orcid":false,"given":"Jing","family":"Shu","sequence":"first","affiliation":[{"name":"Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong SAR 999077, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8835-7896","authenticated-orcid":false,"given":"Junming","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong SAR 999077, China"}]},{"given":"Sanders Cheuk Yin","family":"Lau","sequence":"additional","affiliation":[{"name":"Department of Aeronautics, Imperial College London, London SW7 2BX, UK"}]},{"given":"Yujie","family":"Su","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong SAR 999077, China"}]},{"given":"Kelvin Ho Lam","family":"Heung","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong SAR 999077, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9435-1244","authenticated-orcid":false,"given":"Xiangqian","family":"Shi","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong SAR 999077, China"}]},{"given":"Zheng","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong SAR 999077, China"},{"name":"Department of Surgery, The Chinese University of Hong Kong, Hong Kong SAR 999077, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4375-653X","authenticated-orcid":false,"given":"Raymond Kai-yu","family":"Tong","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong SAR 999077, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"467","DOI":"10.1038\/nature14543","article-title":"Design, fabrication and control of soft robots","volume":"521","author":"Rus","year":"2015","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"105017","DOI":"10.1088\/0964-1726\/20\/10\/105017","article-title":"A non-differential elastomer curvature sensor for softer-than-skin electronics","volume":"20","author":"Majidi","year":"2011","journal-title":"Smart Mater. 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