{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T09:50:37Z","timestamp":1780912237390,"version":"3.54.1"},"reference-count":46,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2018,2,13]],"date-time":"2018-02-13T00:00:00Z","timestamp":1518480000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, we propose a compact force sensor system for a hip-mounted exoskeleton for seniors with difficulties in walking due to muscle weakness. It senses and monitors the delivered force and power of the exoskeleton for motion control and taking urgent safety action. Two FSR (force-sensitive resistors) sensors are used to measure the assistance force when the user is walking. The sensor system directly measures the interaction force between the exoskeleton and the lower limb of the user instead of a previously reported force-sensing method, which estimated the hip assistance force from the current of the motor and lookup tables. Furthermore, the sensor system has the advantage of generating torque in the walking-assistant actuator based on directly measuring the hip-assistance force. Thus, the gait-assistance exoskeleton system can control the delivered power and torque to the user. The force sensing structure is designed to decouple the force caused by hip motion from other directional forces to the sensor so as to only measure that force. We confirmed that the hip-assistance force could be measured with the proposed prototype compact force sensor attached to a thigh frame through an experiment with a real system.<\/jats:p>","DOI":"10.3390\/s18020566","type":"journal-article","created":{"date-parts":[[2018,2,13]],"date-time":"2018-02-13T05:32:19Z","timestamp":1518499939000},"page":"566","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":42,"title":["Compact Hip-Force Sensor for a Gait-Assistance Exoskeleton System"],"prefix":"10.3390","volume":"18","author":[{"given":"Hyundo","family":"Choi","sequence":"first","affiliation":[{"name":"Device &amp; System Research Center, Samsung Advanced Institute of Technology, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keehong","family":"Seo","sequence":"additional","affiliation":[{"name":"Device &amp; System Research Center, Samsung Advanced Institute of Technology, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seungyong","family":"Hyung","sequence":"additional","affiliation":[{"name":"Device &amp; System Research Center, Samsung Advanced Institute of Technology, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Youngbo","family":"Shim","sequence":"additional","affiliation":[{"name":"Device &amp; System Research Center, Samsung Advanced Institute of Technology, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Soo-Chul","family":"Lim","sequence":"additional","affiliation":[{"name":"Department of Mechanical, Robotics and Energy Engineering, Dongguk University, 30, Pildong-ro 1gil, Jung-gu, Seoul 04620, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,2,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"412","DOI":"10.1093\/ageing\/afq034","article-title":"Sarcopenia: European consensus on definition and diagnosis: Report of the European working group on Sarcopenia in older people","volume":"39","author":"Baeyens","year":"2010","journal-title":"Age Aging"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"407","DOI":"10.1007\/PL00004148","article-title":"World-wide projections for hip fracture","volume":"7","author":"Gullberg","year":"1997","journal-title":"Osteoporos. 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