{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T13:42:25Z","timestamp":1762177345493,"version":"build-2065373602"},"reference-count":55,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2020,10,15]],"date-time":"2020-10-15T00:00:00Z","timestamp":1602720000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key R&amp;D Program of China","award":["2018YFB1305400 & 2017YFB1302301"],"award-info":[{"award-number":["2018YFB1305400 & 2017YFB1302301"]}]},{"name":"Joint Research Fund  between the National Nature Science Foundation of China (NSFC) and Shen Zhen","award":["U1713201 & U1613219"],"award-info":[{"award-number":["U1713201 & U1613219"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Tripping is a common problem that everyone faces when walking. This paper mainly focuses on a lower limb exoskeleton that can help those weak in joints to avoid tripping when negotiating stairs or stepping over obstacles. This method does not need a camera or map reconstruction to recognize the obstacles and plan paths. The exoskeleton applies an impedance controller to follow and control the pilot\u2019s movements. A virtual potential field is proposed to help the robot regulate the pilot\u2019s motion and avoid kicking the obstacles appearing in front of the pilot\u2019s foot during walking. Simulation and experiments show that this method works effectively and could help the elderly and those affected by joint weakness avoid tripping when walking.<\/jats:p>","DOI":"10.3390\/s20205844","type":"journal-article","created":{"date-parts":[[2020,10,15]],"date-time":"2020-10-15T21:42:21Z","timestamp":1602798141000},"page":"5844","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Tripping Avoidance Lower Extremity Exoskeleton Based on Virtual Potential Field for Elderly People"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5636-8742","authenticated-orcid":false,"given":"Zongwei","family":"Zhang","sequence":"first","affiliation":[{"name":"State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Changle","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tianjiao","family":"Zheng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hongwu","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sikai","family":"Zhao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jie","family":"Zhao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yanhe","family":"Zhu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"554","DOI":"10.1136\/bmj.322.7285.554","article-title":"Guidelines for prevention of falls in people aged over 65","volume":"322","author":"James","year":"2001","journal-title":"BMJ"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"S13","DOI":"10.1016\/j.arr.2010.07.002","article-title":"Falls in aged people of the Chinese mainland: Epidemiology, risk factors and clinical strategies","volume":"9","author":"Wang","year":"2010","journal-title":"Ageing Res. 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