{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T11:43:47Z","timestamp":1776167027874,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T00:00:00Z","timestamp":1776124800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Jordan Scientific Research and Innovation Support Fund","award":["ENG\/1\/10\/2020"],"award-info":[{"award-number":["ENG\/1\/10\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>Wireless Capsule Endoscopy (WCE) is a minimally invasive technology for imaging the gastrointestinal (GI) tract, particularly the small intestine, where conventional endoscopy faces accessibility limitations. Traditional capsule endoscopes rely on passive motion driven by natural peristalsis, which limits controllability and may increase the risk of capsule retention. To address these challenges, this study presents the design and experimental validation of a compliant active capsule endoscope actuated by four Shape Memory Alloy (SMA) spring actuators. A key feature of the proposed system is a steering mechanism that reuses the same SMA actuators responsible for locomotion, enabling control of the camera orientation without increasing system complexity, size, or weight. The capsule architecture consists of rigid polylactic acid (PLA) links connected through thermoplastic polyurethane (TPU) flexure hinges, fabricated using dual-material 3D printing. Nonlinear finite element analysis (FEA) was employed to optimize the flexure hinge geometry for maximum displacement while maintaining safe stress levels. To validate the concept, a 3.5\u00d7 scaled prototype was fabricated and integrated with SMA actuators and an Arduino-based control system. The experimental results demonstrate effective locomotion and steering capabilities, achieving a maximum stroke of approximately 5.4 mm and a steering angle of 24\u00b0 for the 3.5\u00d7 scaled prototype, corresponding to an estimated stroke of approximately 1.98 mm (Based on the FEA) at the intended clinical scale. Thermal characterization of the SMA actuators was also conducted to identify suitable operating current ranges for future biomedical deployment. The results demonstrate the feasibility of integrating locomotion and steering within a compact compliant capsule architecture, representing a step toward next-generation capsule endoscopy systems with improved navigation and diagnostic capability.<\/jats:p>","DOI":"10.3390\/mi17040471","type":"journal-article","created":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T10:29:08Z","timestamp":1776162548000},"page":"471","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Compliant SMA-Actuated Capsule Robot with Integrated Locomotion and Steering for Wireless Capsule Endoscopy"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7285-7749","authenticated-orcid":false,"given":"Ahmad M.","family":"Alshorman","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, Jordan University of Science and Technology, Irbid 22110, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bashar Sh.","family":"Al-zu\u2019bi","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, Jordan University of Science and Technology, Irbid 22110, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Omar A.","family":"Ababneh","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, Jordan University of Science and Technology, Irbid 22110, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abdel Rahman","family":"Al Manasra","sequence":"additional","affiliation":[{"name":"Department of General Surgery and Urology, Faculty of Medicine, Jordan University of Science and Technology, Irbid 22110, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Khaled","family":"Alshurman","sequence":"additional","affiliation":[{"name":"Electrical and Electronics Engineering Department, Hubei Polytechnic University in Huangshi, Huangshi 435000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tarik","family":"Alhmoud","sequence":"additional","affiliation":[{"name":"Gastroentetology and Hepatology Division, King Hussien Cancer Center, Amman 11118, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"235","DOI":"10.1007\/s10544-006-9025-3","article-title":"Wireless capsule endoscopy: From diagnostic devices to multipurpose robotic systems","volume":"9","author":"Moglia","year":"2007","journal-title":"Biomed. 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