{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T21:06:06Z","timestamp":1784667966055,"version":"3.55.0"},"reference-count":44,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2022,11,6]],"date-time":"2022-11-06T00:00:00Z","timestamp":1667692800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["52027806"],"award-info":[{"award-number":["52027806"]}]},{"name":"National Natural Science Foundation of China","award":["U1913601"],"award-info":[{"award-number":["U1913601"]}]},{"name":"National Natural Science Foundation of China","award":["52075191"],"award-info":[{"award-number":["52075191"]}]},{"name":"National Natural Science Foundation of China","award":["U1913205"],"award-info":[{"award-number":["U1913205"]}]},{"name":"Program for HUST Academic Frontier Youth Team","award":["52027806"],"award-info":[{"award-number":["52027806"]}]},{"name":"Program for HUST Academic Frontier Youth Team","award":["U1913601"],"award-info":[{"award-number":["U1913601"]}]},{"name":"Program for HUST Academic Frontier Youth Team","award":["52075191"],"award-info":[{"award-number":["52075191"]}]},{"name":"Program for HUST Academic Frontier Youth Team","award":["U1913205"],"award-info":[{"award-number":["U1913205"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Researchers have made advances in reducing the metabolic rate of both walking and running by modulating mono-articular energy with exoskeletons. However, how to modulate multiarticular energy with exoskeletons to improve the energy economy of both walking and running is still a challenging problem, due to the lack of understanding of energy transfer among human lower-limb joints. Based on the study of the energy recycling and energy transfer function of biarticular muscles, we proposed a hip\u2013knee unpowered exoskeleton that emulates and reinforces the function of the hamstrings and rectus femoris in different gait phases. The biarticular exo-tendon of the exoskeleton assists hamstrings to recycle the kinetic energy of the leg swing while providing hip extension torque in the swing phase. In the following stance phase, the exo-tendon releases the stored energy to assist the co-contraction of gluteus maximus and rectus femoris for both hip extension and knee extension, thus realizing the phased modulation of hip and knee joint energy. The metabolic rate of both walking (1.5 m\/s) and running (2.5 m\/s) can be reduced by 6.2% and 4.0% with the multiarticular energy modulation of a hip\u2013knee unpowered exoskeleton, compared to that of walking and running without an exoskeleton. The bio-inspired design method of this study may inspire people to develop devices that assist multiple gaits in the future.<\/jats:p>","DOI":"10.3390\/s22218539","type":"journal-article","created":{"date-parts":[[2022,11,7]],"date-time":"2022-11-07T03:02:22Z","timestamp":1667790142000},"page":"8539","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Modulating Multiarticular Energy during Human Walking and Running with an Unpowered Exoskeleton"],"prefix":"10.3390","volume":"22","author":[{"given":"Tiancheng","family":"Zhou","sequence":"first","affiliation":[{"name":"State Key Laboratory of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Institute of Medical Equipment Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhijie","family":"Zhou","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Institute of Medical Equipment Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hanwen","family":"Zhang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Institute of Medical Equipment Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2273-1934","authenticated-orcid":false,"given":"Wenbin","family":"Chen","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Institute of Medical Equipment Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s12984-020-00663-9","article-title":"The exoskeleton expansion: Improving walking and running economy","volume":"17","author":"Sawicki","year":"2020","journal-title":"J. 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