{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T10:00:21Z","timestamp":1780912821896,"version":"3.54.1"},"reference-count":51,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,1,29]],"date-time":"2022-01-29T00:00:00Z","timestamp":1643414400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the National Key Research and Development Program of China","award":["2018YFB1305400"],"award-info":[{"award-number":["2018YFB1305400"]}]},{"name":"the National Natural Science Foundation of China (NSFC)","award":["52105016"],"award-info":[{"award-number":["52105016"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Weight-bearing exoskeletons are robots that need to carry loads and interact with humans frequently. Therefore, the actuators of these exoskeletons are supposed to be capable of outputting sufficient force with high compliance and little weight. A series\u2013parallel elastic actuator (SPEA) is designed, in this work, to meet the demanding requirements of an exoskeleton robot called PALExo. A gas spring is installed in parallel with an electric cylinder to adjust the force output range of the actuator according to the needs of the exoskeleton. A series elastic module (SEM) is installed in series with the electric cylinder and gas spring to improve the compliance of the actuator, the stiffness of which is variable to adapt to the different stiffness requirements of the exoskeleton\u2019s legs in the standing phase and swinging phase. A force controller combining dynamic compensation and a cascade control with an inner velocity loop and a disturbance observer is designed for the SPEA. The performance of the force controller is verified by experiments and the results demonstrate that the controller has good adaptability to the stiffness of the SEM.<\/jats:p>","DOI":"10.3390\/s22031055","type":"journal-article","created":{"date-parts":[[2022,1,30]],"date-time":"2022-01-30T00:12:56Z","timestamp":1643501576000},"page":"1055","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Design and Control of a Series\u2013Parallel Elastic Actuator for a Weight-Bearing Exoskeleton Robot"],"prefix":"10.3390","volume":"22","author":[{"given":"Tianshuo","family":"Wang","sequence":"first","affiliation":[{"name":"State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tianjiao","family":"Zheng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sikai","family":"Zhao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dongbao","family":"Sui","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Zhao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanhe","family":"Zhu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,29]]},"reference":[{"key":"ref_1","first-page":"588","article-title":"Handyman to hardiman","volume":"76","author":"Mosher","year":"1968","journal-title":"Sae Trans."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Villani, L., and De Schutter, J. 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