{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T00:09:19Z","timestamp":1771632559530,"version":"3.50.1"},"reference-count":27,"publisher":"Cambridge University Press (CUP)","issue":"9","license":[{"start":{"date-parts":[[2014,12,12]],"date-time":"2014-12-12T00:00:00Z","timestamp":1418342400000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Robotica"],"published-print":{"date-parts":[[2016,9]]},"abstract":"<jats:title>SUMMARY<\/jats:title><jats:p>Singularities have a great influence on kinematics and dynamics of both serial and parallel robots. In order to prevent a robot from entering singular configurations, it needs to measure the \u201cdistance\u201d between the robot current configuration and the singular configuration. This paper presents a novel approach based on characteristic angles to measure closeness to singularities. For the problem of inconsistent dimensions in the scalar product of screws, the physical meanings of twists and wrenches are reinterpreted. For the problem of the metric invariant to origin selection, the origin of the screw frame is required to coincide with the origin of the robotic tool frame. The major merit of the proposed metric lies in the identical result of measuring similar mechanisms with different sizes. Moreover, the measurement is insensitive to screw magnitude, since the metric expression is dimensionless. Furthermore, the geometrical meaning of the determinant of a screw matrix is clarified.<\/jats:p>","DOI":"10.1017\/s0263574714002823","type":"journal-article","created":{"date-parts":[[2014,12,12]],"date-time":"2014-12-12T03:06:37Z","timestamp":1418353597000},"page":"2105-2115","source":"Crossref","is-referenced-by-count":13,"title":["Closeness to singularities of robotic manipulators measured by characteristic angles"],"prefix":"10.1017","volume":"34","author":[{"given":"Wanghui","family":"Bu","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"56","published-online":{"date-parts":[[2014,12,12]]},"reference":[{"key":"S0263574714002823_ref7","volume-title":"A Mathematical Introduction to Robotic Manipulation","author":"Murray","year":"1994"},{"key":"S0263574714002823_ref10","doi-asserted-by":"publisher","DOI":"10.1109\/TRO.2009.2020353"},{"key":"S0263574714002823_ref13","doi-asserted-by":"publisher","DOI":"10.1109\/70.388791"},{"key":"S0263574714002823_ref22","doi-asserted-by":"publisher","DOI":"10.1177\/027836499201100303"},{"key":"S0263574714002823_ref17","doi-asserted-by":"publisher","DOI":"10.1177\/095440620121500101"},{"key":"S0263574714002823_ref16","doi-asserted-by":"publisher","DOI":"10.1115\/1.2961335"},{"key":"S0263574714002823_ref8","unstructured":"D. Zlatanov , I. A. Bonev and C. M. Gosselin , \u201cConstraint Singularities of Parallel Manipulators,\u201d IEEE International Conference on Robotics and Automation, Washington, DC, (2002) pp. 496\u2013502."},{"key":"S0263574714002823_ref24","volume-title":"Geometric Fundamentals of Robotics","author":"Selig","year":"2004"},{"key":"S0263574714002823_ref6","doi-asserted-by":"publisher","DOI":"10.1016\/S0094-114X(97)00098-0"},{"key":"S0263574714002823_ref27","doi-asserted-by":"publisher","DOI":"10.1016\/j.mechmachtheory.2006.01.006"},{"key":"S0263574714002823_ref23","doi-asserted-by":"publisher","DOI":"10.1016\/j.mechmachtheory.2006.03.010"},{"key":"S0263574714002823_ref15","doi-asserted-by":"publisher","DOI":"10.1109\/TRO.2005.855993"},{"key":"S0263574714002823_ref18","doi-asserted-by":"publisher","DOI":"10.1243\/09544062C17204"},{"key":"S0263574714002823_ref9","doi-asserted-by":"publisher","DOI":"10.1016\/S0094-114X(97)00053-0"},{"key":"S0263574714002823_ref3","first-page":"1","article-title":"Forward displacement analysis and singularity analysis of a special 2-DOF 5R spherical parallel manipulator","volume":"3","author":"Kong","year":"2011","journal-title":"ASME J. Mech. Robot."},{"key":"S0263574714002823_ref1","doi-asserted-by":"publisher","DOI":"10.1115\/1.4005524"},{"key":"S0263574714002823_ref2","doi-asserted-by":"publisher","DOI":"10.1016\/j.mechmachtheory.2008.07.005"},{"key":"S0263574714002823_ref12","doi-asserted-by":"publisher","DOI":"10.1115\/1.2121740"},{"key":"S0263574714002823_ref11","doi-asserted-by":"publisher","DOI":"10.1177\/027836498500400201"},{"key":"S0263574714002823_ref5","doi-asserted-by":"publisher","DOI":"10.1115\/1.2829426"},{"key":"S0263574714002823_ref19","doi-asserted-by":"publisher","DOI":"10.1115\/1.4007004"},{"key":"S0263574714002823_ref25","doi-asserted-by":"publisher","DOI":"10.1115\/1.1469549"},{"key":"S0263574714002823_ref21","doi-asserted-by":"publisher","DOI":"10.1115\/1.2829417"},{"key":"S0263574714002823_ref20","first-page":"386","article-title":"Discussion: \u2018The elliptic polarity of screws\u2019","volume":"107","author":"McCarthy","year":"1985","journal-title":"ASME J. Mech. Des."},{"key":"S0263574714002823_ref4","doi-asserted-by":"crossref","first-page":"579","DOI":"10.1109\/TRA.2003.814507","article-title":"Singularities of parallel manipulators: A geometric treatment","volume":"19","author":"Liu","year":"2003","journal-title":"IEEE Trans. Robot. Autom."},{"key":"S0263574714002823_ref14","first-page":"377","article-title":"The elliptic polarity of screws","volume":"107","author":"Lipkin","year":"1985","journal-title":"ASME J. Mech. Des."},{"key":"S0263574714002823_ref26","doi-asserted-by":"publisher","DOI":"10.1115\/1.4002696"}],"container-title":["Robotica"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.cambridge.org\/core\/services\/aop-cambridge-core\/content\/view\/S0263574714002823","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,4,18]],"date-time":"2019-04-18T19:58:40Z","timestamp":1555617520000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.cambridge.org\/core\/product\/identifier\/S0263574714002823\/type\/journal_article"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,12,12]]},"references-count":27,"journal-issue":{"issue":"9","published-print":{"date-parts":[[2016,9]]}},"alternative-id":["S0263574714002823"],"URL":"https:\/\/doi.org\/10.1017\/s0263574714002823","relation":{},"ISSN":["0263-5747","1469-8668"],"issn-type":[{"value":"0263-5747","type":"print"},{"value":"1469-8668","type":"electronic"}],"subject":[],"published":{"date-parts":[[2014,12,12]]}}}