{"id":304616,"date":"2023-09-01T21:11:23","date_gmt":"2023-09-01T21:11:23","guid":{"rendered":"\/forum\/forums\/reply\/304616\/"},"modified":"2023-09-01T21:11:23","modified_gmt":"2023-09-01T21:11:23","slug":"304616","status":"publish","type":"reply","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/304616\/","title":{"rendered":"Reply To: Question about the definition of rigid part rotating around certain location and"},"content":{"rendered":"<p>&lt;p&gt;Hello Ying,&lt;\/p&gt;&lt;p&gt;For a rigid body, the axis of rotation is always through the center of mass. Here is an excerpt from the LS-DYNA User Manual Vol I for *BOUNDARY_PRESCRIBED_MOTION:&lt;\/p&gt;&lt;p&gt;<img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/09\/01-09-2023-1693602598-mceclip0.png\" \/>&lt;\/p&gt;&lt;p&gt;&nbsp;&lt;\/p&gt;&lt;p&gt;So, I guess the center of mass of your rigid body is aligned with the CG point correct? Have&nbsp; you tried to moved the rigid body so that its center of mass is aligned with point OC for method 2?&lt;\/p&gt;&lt;p&gt;&nbsp;&lt;\/p&gt;&lt;p&gt;Let&nbsp; me know if this helps or not.&lt;\/p&gt;&lt;p&gt;&nbsp;&lt;\/p&gt;&lt;p&gt;Reno.&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-304616","reply","type-reply","status-publish","hentry"],"aioseo_notices":[],"acf":[],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies\/304616","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/reply"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies\/304616\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=304616"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}