{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T16:30:46Z","timestamp":1775838646180,"version":"3.50.1"},"reference-count":47,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,4,22]],"date-time":"2022-04-22T00:00:00Z","timestamp":1650585600000},"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>In this article, a soft robot arm that has the ability to twist in two directions is designed. This continuum arm is inspired by the twisting movements of the human upper limb. In this novel continuum arm, two contractor pneumatic muscle actuators (PMA) are used in parallel, and a self-bending contraction actuator (SBCA) is laid between them to establish the twisting movement. The proposed soft robot arm has additional features, such as the ability to contract and bend in multiple directions. The kinematics for the proposed arm is presented to describe the position of the distal end centre according to the dimensions and positions of the actuators and the bending angle of the SBCA in different pressurized conditions. Then, the rotation behaviour is controlled by a high precision controller system.<\/jats:p>","DOI":"10.3390\/robotics11030055","type":"journal-article","created":{"date-parts":[[2022,4,24]],"date-time":"2022-04-24T00:45:21Z","timestamp":1650761121000},"page":"55","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Design, Implementation, and Kinematics of a Twisting Robot Continuum Arm Inspired by Human Forearm Movements"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0779-8217","authenticated-orcid":false,"given":"Alaa","family":"Al-Ibadi","sequence":"first","affiliation":[{"name":"Computer Engineering Department, University of Basrah, Basrah 64001, Iraq"},{"name":"School of Computing, Science and Engineering, University of Salford, Salford M5 4WT, UK"}]},{"given":"Khalid A.","family":"Abbas","sequence":"additional","affiliation":[{"name":"Computer Engineering Department, University of Basrah, Basrah 64001, Iraq"}]},{"given":"Mohammed","family":"Al-Atwani","sequence":"additional","affiliation":[{"name":"Computer Engineering Department, University of Basrah, Basrah 64001, Iraq"}]},{"given":"Hassanin","family":"Al-Fahaam","sequence":"additional","affiliation":[{"name":"Computer Engineering Department, University of Basrah, Basrah 64001, Iraq"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,22]]},"reference":[{"key":"ref_1","first-page":"112","article-title":"Theoretical and Experimental Modeling of Air Muscle","volume":"2","author":"Ranjan","year":"2012","journal-title":"J. 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