{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T16:54:49Z","timestamp":1776444889739,"version":"3.51.2"},"reference-count":46,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,10,10]],"date-time":"2024-10-10T00:00:00Z","timestamp":1728518400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Second Century Fund (C2F), Chulalongkorn University"},{"name":"Thailand Science Research and Innovation Fund, Chulalongkorn University"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JSAN"],"abstract":"<jats:p>Enhancing the transparency of high-transmission-ratio linear actuators is crucial for improving the safety and capability of high-force robotic systems having physical contact with humans in unstructured environments. However, realizing such enhancement is challenging. A proposed solution for active body weight support systems involves employing a macro\u2013mini linear actuator incorporating an electrorheological-fluid brake to connect a high-force unit with an agile, highly back-drivable unit. This paper introduces the use of an electromagnetic (EM) brake with reduced rotor inertia to address this challenge. The increased torque capacity of the EM brake enables integration with a low-gear-ratio linear transmission. The agile translation of the endpoint is propelled by a low-inertia motor (referred to as the \u201cmini\u201d) via a pulley-belt mechanism to achieve high transparency. The rotor of the EM brake is linked to the pulley. Damping modulation under high driving force is achieved through the adjustment of the brake torque relative to the rotational speed of the pulley. When the brake is engaged, it prevents any relative motion between the endpoint and the moving carrier. The endpoint is fully controlled by the ball screw of the high-force unit, referred to as the \u201cmacro\u201d. A scaled prototype was constructed to experimentally characterize the damping force generated by the mini motor and the EM brake. The macro\u2013mini linear actuator, equipped with an intrinsic failsafe feature, can be utilized for active body weight support systems that demand high antigravity force.<\/jats:p>","DOI":"10.3390\/jsan13050065","type":"journal-article","created":{"date-parts":[[2024,10,10]],"date-time":"2024-10-10T07:53:05Z","timestamp":1728546785000},"page":"65","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["High-Transparency Linear Actuator Using an Electromagnetic Brake for Damping Modulation in Physical Human\u2013Robot Interaction"],"prefix":"10.3390","volume":"13","author":[{"given":"Zahid","family":"Ullah","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thachapan","family":"Sermsrisuwan","sequence":"additional","affiliation":[{"name":"International School of Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Khemwutta","family":"Pornpipatsakul","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5002-7568","authenticated-orcid":false,"given":"Ronnapee","family":"Chaichaowarat","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"},{"name":"International School of Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Witaya","family":"Wannasuphoprasit","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"311","DOI":"10.1109\/TNSRE.2006.881556","article-title":"A novel mechatronic body weight support system","volume":"14","author":"Frey","year":"2006","journal-title":"IEEE Trans. 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