{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,30]],"date-time":"2025-12-30T08:55:17Z","timestamp":1767084917251,"version":"3.41.2"},"reference-count":29,"publisher":"Emerald","issue":"3","license":[{"start":{"date-parts":[[2015,5,18]],"date-time":"2015-05-18T00:00:00Z","timestamp":1431907200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.emerald.com\/insight\/site-policies"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IR"],"published-print":{"date-parts":[[2015,5,18]]},"abstract":"<jats:sec>\n<jats:title content-type=\"abstract-subheading\">Purpose<\/jats:title>\n<jats:p>This paper aims to discuss, analyze and compare members of a group of actuators with adjustable stiffness, namely: AwAS, AwAS-II and CompACT variable stiffness actuator (VSA) developed at Italian Institute of Technology (IIT).<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title content-type=\"abstract-subheading\">Design\/methodology\/approach<\/jats:title>\n<jats:p>These actuators are among series type of VSAs where one main motor is dedicated for link positioning and a secondary motor, in series with the first one, regulates the output link stiffness. Regulating the stiffness in this group of actuators is based on the lever concept. Initially, springs were moved along the lever to tune the stiffness while in the later versions stiffness was regulated through relocating pivot point along the lever.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title content-type=\"abstract-subheading\">Findings<\/jats:title>\n<jats:p>This paper discusses how different mechanisms have been employed in realization of the lever concept in these actuators and what are the advantages and disadvantages of each realization.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title content-type=\"abstract-subheading\">Practical implications<\/jats:title>\n<jats:p>Today\u2019s robots are not supposed to be solid, isolated and rigid anymore but rather adaptive, cooperative and compliant entities in our daily life. The new attitudes demand for novel technologies substantially different from those developed for industrial domains both at the hardware and the software levels. This work presents latest three state-of-the-art actuators, developed at IIT, which are great answers to the needs of tomorrow\u2019s robot.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title content-type=\"abstract-subheading\">Originality\/value<\/jats:title>\n<jats:p>These novel actuators are really ready for commercial exploitation, as they are compact and reliable. The main novelty is based on employing concept of lever mechanism for stiffness regulation. They have been designed and manufactured in a very professional and optimized way.<\/jats:p>\n<\/jats:sec>","DOI":"10.1108\/ir-12-2014-0433","type":"journal-article","created":{"date-parts":[[2015,5,26]],"date-time":"2015-05-26T10:16:27Z","timestamp":1432635387000},"page":"242-251","source":"Crossref","is-referenced-by-count":27,"title":["Energy efficient actuators with adjustable stiffness: a review on AwAS, AwAS-II and CompACT VSA changing stiffness based on lever mechanism"],"prefix":"10.1108","volume":"42","author":[{"given":"Amir","family":"Jafari","sequence":"first","affiliation":[]},{"given":"Nikos","family":"Tsagarakis","sequence":"additional","affiliation":[]},{"given":"Darwin","family":"Caldwell","sequence":"additional","affiliation":[]}],"member":"140","reference":[{"key":"key2020122421522169000_ref001","first-page":"6472","article-title":"Evaluation of direct and indirect haptic aiding in an obstacle avoidance task for tele-operated systems","volume-title":"In: Red Hook","year":"2011"},{"first-page":"1825","article-title":"A proof-of-concept exoskeleton for robot assisted rehabilitation of gait","year":"2009","key":"key2020122421522169000_ref002"},{"year":"2004","key":"key2020122421522169000_ref003","article-title":"Fast and soft tactile [robot arm design] actuator for machines interacting with humans"},{"year":"2011","key":"key2020122421522169000_ref004","article-title":"Passive multirate wave communications for haptic interaction in slow virtual environments"},{"year":"2011","key":"key2020122421522169000_ref005","article-title":"Vsa-cubebot: a modular variable stiffness platform for multiple degrees of freedom robots"},{"year":"2010","key":"key2020122421522169000_ref006","article-title":"Design of the amp-foot 2.0: an active trans-tibial prosthesis that mimics able-bodied ankle behavior"},{"key":"key2020122421522169000_ref007","unstructured":"Darden, D. 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