{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T01:49:39Z","timestamp":1777427379553,"version":"3.51.4"},"reference-count":56,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,5,7]],"date-time":"2021-05-07T00:00:00Z","timestamp":1620345600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science, Technology and Innovation of Colombia","award":["801-2017"],"award-info":[{"award-number":["801-2017"]}]},{"name":"Ministry of Science, Technology and Innovation of Colombia","award":["845-2020"],"award-info":[{"award-number":["845-2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Smart walkers are commonly used as potential gait assistance devices, to provide physical and cognitive assistance within rehabilitation and clinical scenarios. To understand such rehabilitation processes, several biomechanical studies have been conducted to assess human gait with passive and active walkers. Several sessions were conducted with 11 healthy volunteers to assess three interaction strategies based on passive, low and high mechanical stiffness values on the AGoRA Smart Walker. The trials were carried out in a motion analysis laboratory. Kinematic data were also collected from the smart walker sensory interface. The interaction force between users and the device was recorded. The force required under passive and low stiffness modes was 56.66% and 67.48% smaller than the high stiffness mode, respectively. An increase of 17.03% for the hip range of motion, as well as the highest trunk\u2019s inclination, were obtained under the resistive mode, suggesting a compensating motion to exert a higher impulse force on the device. Kinematic and physical interaction data suggested that the high stiffness mode significantly affected the users\u2019 gait pattern. Results suggested that users compensated their kinematics, tilting their trunk and lower limbs to exert higher impulse forces on the device.<\/jats:p>","DOI":"10.3390\/s21093242","type":"journal-article","created":{"date-parts":[[2021,5,7]],"date-time":"2021-05-07T22:36:24Z","timestamp":1620426984000},"page":"3242","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Evaluation of Physical Interaction during Walker-Assisted Gait with the AGoRA Walker: Strategies Based on Virtual Mechanical Stiffness"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5714-1478","authenticated-orcid":false,"given":"Sergio D.","family":"Sierra M","sequence":"first","affiliation":[{"name":"Department of Biomedical Engineering, Colombian School of Engineering Julio Garavito, Bogot\u00e1 111166, Colombia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6595-5383","authenticated-orcid":false,"given":"Marcela","family":"M\u00fanera","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Colombian School of Engineering Julio Garavito, Bogot\u00e1 111166, Colombia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4610-9231","authenticated-orcid":false,"given":"Thomas","family":"Provot","sequence":"additional","affiliation":[{"name":"EPF\u2014Graduate School of Engineering, F-92330 Sceaux, France"},{"name":"Arts et M\u00e9tiers Institute of Technology, Institut de Biom\u00e9canique Humaine Georges Charpak, IBHGC, UR 4494, F-75013 Paris; Universit\u00e9 Sorbonne Paris Nord, F-93000 Bobigny, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0178-4858","authenticated-orcid":false,"given":"Maxime","family":"Bourgain","sequence":"additional","affiliation":[{"name":"EPF\u2014Graduate School of Engineering, F-92330 Sceaux, France"},{"name":"Arts et M\u00e9tiers Institute of Technology, Institut de Biom\u00e9canique Humaine Georges Charpak, IBHGC, UR 4494, F-75013 Paris; Universit\u00e9 Sorbonne Paris Nord, F-93000 Bobigny, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6942-865X","authenticated-orcid":false,"given":"Carlos A.","family":"Cifuentes","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Colombian School of Engineering Julio Garavito, Bogot\u00e1 111166, Colombia"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,7]]},"reference":[{"key":"ref_1","first-page":"2","article-title":"Complexity and Human Gait","volume":"3","author":"Decker","year":"2010","journal-title":"Rev. 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