{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,18]],"date-time":"2026-10-18T06:34:39Z","timestamp":1792305279220,"version":"4.4.0"},"reference-count":29,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T00:00:00Z","timestamp":1775088000000},"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. Bioeng. Biotechnol."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Honeycomb sandwich composites are widely employed in aerospace and structural applications due to their high specific strength and efficient energy storage and return, offering a promising design alternative for running prostheses.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This study investigates the mechanical performance of a running prosthetic foot designed with an aluminum honeycomb core (AMS 3711) and carbon fiber skins, comparing it against a conventional solid epoxy-carbon laminate. A finite element model was developed in ANSYS following ISO 10328 boundary and loading conditions. The analysis evaluated six design configurations, transitioning from a solid reference blade to optimized sandwich structures. Static analyses were performed at two gait-cycle positions defined by ISO 10328 to evaluate mass, deformation, equivalent stress, strain energy, and safety factors across varying core and surface-layer thicknesses under constant total volume.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The results demonstrated that the optimized sandwich design achieved a 63.9% reduction in distal mass (from 1.33 kg to 0.48 kg) compared to the solid counterpart. Contrary to the typical trade-off between lightweighting and energy capacity, the increased compliance of the sandwich structure resulted in a 57.4% increase in strain energy storage. Although the transition to a cellular core initially reduced the safety margin, geometric optimization of the core thickness recovered structural integrity, achieving a safety factor of 1.95, well above the recommended threshold of 1.5.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>These findings indicate that honeycomb sandwich architectures offer a superior alternative to solid laminates for running prostheses, simultaneously enhancing energy return efficiency and minimizing structural mass without compromising safety.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fbioe.2026.1785315","type":"journal-article","created":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T05:26:01Z","timestamp":1775107561000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Lightweight design of running prosthetic feet using honeycomb sandwich composites: a comparative FEA study"],"prefix":"10.3389","volume":"14","author":[{"given":"Yunis","family":"Akka\u015f","sequence":"first","affiliation":[{"name":"Department of Orthotics and Prosthetics, Faculty of Health Sciences, Ankara University","place":["Ankara, T\u00fcrkiye"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Serap","family":"Alsancak","sequence":"additional","affiliation":[{"name":"Department of Orthotics and Prosthetics, Faculty of Health Sciences, Ankara University","place":["Ankara, T\u00fcrkiye"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,4,2]]},"reference":[{"key":"B1","volume-title":"Material property data for engineering materials","author":"Ashby","year":"2021"},{"key":"B2","doi-asserted-by":"publisher","first-page":"627","DOI":"10.1177\/10996362211021888","article-title":"In-Plane compression modulus and strength of nomex honeycomb cores","volume":"24","author":"Ayanoglu","year":"2021","journal-title":"J. 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