{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T03:28:15Z","timestamp":1777519695791,"version":"3.51.4"},"reference-count":34,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2019,2,17]],"date-time":"2019-02-17T00:00:00Z","timestamp":1550361600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Robotics"],"abstract":"<jats:p>This article provides a detailed comparative analysis of five orientational, two degrees of freedom (DOF) mechanisms whose envisioned application is the wrist of the iCub humanoid robot. Firstly, the current iCub mk.2 wrist implementation is presented, and the desired design objectives are proposed. Prominent architectures from literature such as the spherical five-bar linkage and spherical six-bar linkage, the OmniWrist-III and the Quaternion joint mechanisms are modeled and analyzed for the said application. Finally, a detailed comparison of their workspace features is presented. The Quaternion joint mechanism emerges as a promising candidate from this study.<\/jats:p>","DOI":"10.3390\/robotics8010011","type":"journal-article","created":{"date-parts":[[2019,2,17]],"date-time":"2019-02-17T22:11:50Z","timestamp":1550441510000},"page":"11","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["A Comparison of Robot Wrist Implementations for the iCub Humanoid \u2020"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1246-5556","authenticated-orcid":false,"given":"Divya","family":"Shah","sequence":"first","affiliation":[{"name":"iCub Facility, Fondazione Istituto Italiano di Tecnologia, 16163 Genova GE, Italy"},{"name":"Dipartimento di Informatica, Bioingegneria, Robotica ed Ingegneria dei Sistemi [DIBRIS], Universit\u00e1 degli Studi di Genova, 16145 Genova GE, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5846-9405","authenticated-orcid":false,"given":"Yuanqing","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, University of Bologna, 40136 Bologna BO, Italy"}]},{"given":"Alessandro","family":"Scalzo","sequence":"additional","affiliation":[{"name":"iCub Facility, Fondazione Istituto Italiano di Tecnologia, 16163 Genova GE, Italy"}]},{"given":"Giorgio","family":"Metta","sequence":"additional","affiliation":[{"name":"iCub Facility, Fondazione Istituto Italiano di Tecnologia, 16163 Genova GE, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1677-9381","authenticated-orcid":false,"given":"Alberto","family":"Parmiggiani","sequence":"additional","affiliation":[{"name":"iCub Facility, Fondazione Istituto Italiano di Tecnologia, 16163 Genova GE, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,17]]},"reference":[{"key":"ref_1","unstructured":"Kong, X., and Gosselin, C.M. 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