{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:45:05Z","timestamp":1788223505375,"version":"build-2803163510"},"reference-count":53,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,10,7]],"date-time":"2025-10-07T00:00:00Z","timestamp":1759795200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomimetics"],"abstract":"<jats:p>This paper presents the foot design for humanoid robot Mithra, with the goal of biomimetically improving impact behavior, natural power cycling throughout the gait cycle, and balance. For this purpose, an optimization framework was built which evaluates the human-inspired objectives using a dynamic finite element analysis validated by benchtop experiments. Using this framework and through several concept design iterations, a low-cost, compliant foot was optimized, designed, and fabricated. The analyses showed that the optimized foot significantly outperformed the baseline rigid foot in approaching the characteristics of human feet. The proposed framework is not limited to humanoids and can also be applied to the foot design for lower-limb prostheses and exoskeletons.<\/jats:p>","DOI":"10.3390\/biomimetics10100675","type":"journal-article","created":{"date-parts":[[2025,10,7]],"date-time":"2025-10-07T15:48:30Z","timestamp":1759852110000},"page":"675","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Design of Human-Inspired Feet to Enhance the Performance of the Humanoid Robot Mithra"],"prefix":"10.3390","volume":"10","author":[{"given":"Spencer","family":"Brewster","sequence":"first","affiliation":[{"name":"Department of Mechanical and Materials Engineering, University of Denver, 2155 East Wesley Avenue, Denver, CO 80210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul J.","family":"Rullkoetter","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Materials Engineering, University of Denver, 2155 East Wesley Avenue, Denver, CO 80210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0312-3167","authenticated-orcid":false,"given":"Siavash","family":"Rezazadeh","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Materials Engineering, University of Denver, 2155 East Wesley Avenue, Denver, CO 80210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/0025-5564(72)90061-2","article-title":"On the stability of anthropomorphic systems","volume":"15","author":"Stepanenko","year":"1972","journal-title":"Math. 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