{"id":458386,"date":"2026-05-18T18:19:49","date_gmt":"2026-05-18T18:19:49","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/constrained-nodal-rigid-body-cnrb\/"},"modified":"2026-05-18T18:19:49","modified_gmt":"2026-05-18T18:19:49","slug":"constrained-nodal-rigid-body-cnrb","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/constrained-nodal-rigid-body-cnrb\/","title":{"rendered":"Constrained Nodal Rigid Body (CNRB)"},"content":{"rendered":"<p>&lt;div class=&#8221;xdj266r x14z9mp xat24cr x1lziwak x1vvkbs&#8221;&gt;&lt;div dir=&#8221;auto&#8221;&gt;Dear colleagues,&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;Below is what I read:&lt;\/div&gt;&lt;p class=&#8221;MsoNormal&#8221; style=&#8221;margin: 6.0pt 0in 6.0pt 0in;&#8221;&gt;&lt;span style=&#8221;color: #ee0000; mso-ansi-language: EN-US;&#8221;&gt;https:\/\/feassistant.com\/forums\/ls-dyna\/how-to-give-displacement-to-constrained-nodal-rigid-body-body\/&lt;\/span&gt;&lt;\/p&gt;&lt;br&gt;&lt;div dir=&#8221;auto&#8221;&gt;I&#8217;m not sure if this is possible, but&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;first you need to make sure that your reference node is the first node in the node set referenced by the constrained nodal rigid body (CNRB).&lt;br&gt;&lt;br&gt;&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;The first node is the source point and represents the center of the CNRB.&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;&lt;br&gt;Then you can try to apply *Boundary_Prescribed_Motion_Node to that reference node.&lt;\/div&gt;&lt;\/div&gt;&lt;div class=&#8221;x14z9mp xat24cr x1lziwak x1vvkbs xtlvy1s&#8221;&gt;&lt;div dir=&#8221;auto&#8221;&gt;&lt;br&gt;If Dyna will not accept this, then you will need a different approach.&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;&lt;br&gt;You can create a simple element (1D, 2D, 3D etc.) which uses that reference node.&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;Then make this part *Mat_rigid.&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;&lt;br&gt;Then you will use *Constrained_extra_nodes_set and refer to the rigid part as the PID and the other nodes will need to be in a node set and be referred to in the NSID.&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;You will then be able to apply motion to the rigid part using *Boundary_prescribed_motion_rigid.&lt;br&gt;&lt;br&gt;==================================================================&lt;br&gt;&lt;div class=&#8221;xdj266r x14z9mp xat24cr x1lziwak x1vvkbs&#8221;&gt;&lt;div dir=&#8221;auto&#8221;&gt;At the same time, in the given model:&lt;\/div&gt;&lt;\/div&gt;&lt;div class=&#8221;x14z9mp xat24cr x1lziwak x1vvkbs xtlvy1s&#8221;&gt;&lt;div dir=&#8221;auto&#8221;&gt;<a href=\"https:\/\/www.dynaexamples.com\/implicit\/Salzburg_2017\/example_linear_3?fbclid=IwZXh0bgNhZW0CMTAAYnJpZBExbWVRdVZjcnI1R2J3cWtsOXNydGMGYXBwX2lkEDIyMjAzOTE3ODgyMDA4OTIAAR7PgUOp1hsO0PZDlSS99P_77OD2MygiriYsVSijWiXVnTTIj-fEBSe6yAarOw_aem_MjqgaoICud3N3GoaWnCdmw\" target=\"_blank\" rel=\"nofollow noopener noreferrer\">https:\/\/www.dynaexamples.com\/&#8230;\/Salzbur&#8230;\/example_linear_3<\/a>&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;&bull; 3.4_Connectors_CNRB_Interpolation.key.zip&lt;br&gt;&lt;br&gt;&lt;\/div&gt;&lt;\/div&gt;&lt;div class=&#8221;x14z9mp xat24cr x1lziwak x1vvkbs xtlvy1s&#8221;&gt;&lt;div dir=&#8221;auto&#8221;&gt;Two parameters are used:&lt;\/div&gt;&lt;\/div&gt;&lt;div class=&#8221;x14z9mp xat24cr x1lziwak x1vvkbs xtlvy1s&#8221;&gt;&lt;div dir=&#8221;auto&#8221;&gt;&lt;br&gt;NSID &#8211; if I understand correctly, this is a set of rigid body points + a &#8220;reference&#8221; point, all of which are fully described by Connectors CNRB.&lt;\/div&gt;&lt;\/div&gt;&lt;div class=&#8221;x14z9mp xat24cr x1lziwak x1vvkbs xtlvy1s&#8221;&gt;&lt;div dir=&#8221;auto&#8221;&gt;&lt;br&gt;At the same time, there is a parameter PID:=Part ID of the nodal rigid body.&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;It is set to 100.&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;&lt;br&gt;If I understand correctly, the number of the &#8220;new&#8221; part defined by the operator:&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;Constrained Nodal Rigid Body (CNRB)&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;&lt;br&gt;But there is no such part in the list of &#8220;parts.&#8221;&lt;\/div&gt;&lt;div dir=&#8221;auto&#8221;&gt;&lt;br&gt;Am I correct in understanding that this part number is an arbitrary number that the user must specify?!&lt;\/div&gt;&lt;\/div&gt;&lt;div class=&#8221;x14z9mp xat24cr x1lziwak x1vvkbs xtlvy1s&#8221;&gt;&lt;div dir=&#8221;auto&#8221;&gt;&lt;br&gt;And one more thing: &lt;br&gt;AFTER solving this problem, a new body, &#8220;10000000 Beam,&#8221; appears in the list of &#8220;parts.&#8221; &lt;br&gt;Before solving this problem, the &#8220;10000000 Beam&#8221; body wasn&#8217;t listed as &#8220;parts.&#8221;&lt;br&gt;&lt;br&gt;&lt;\/div&gt;&lt;\/div&gt;&lt;div class=&#8221;x14z9mp xat24cr x1lziwak x1vvkbs xtlvy1s&#8221;&gt;&lt;div dir=&#8221;auto&#8221;&gt;Can anyone comment on my questions?&lt;\/div&gt;&lt;\/div&gt;&lt;br&gt;&lt;br&gt;&lt;\/div&gt;&lt;\/div&gt;<\/p>\n","protected":false},"template":"","class_list":["post-458386","topic","type-topic","status-publish","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":["27814"],"_bbp_topic_id":["458386"],"_bbp_subscription":["469525","679600"],"_bbp_author_ip":["185.213.209.137"],"_bbp_last_reply_id":["458465"],"_bbp_last_active_id":["458465"],"_bbp_last_active_time":["2026-05-19 15:45:52"],"_bbp_reply_count":["1"],"_bbp_reply_count_hidden":["0"],"_bbp_voice_count":["2"],"_bbp_engagement":["469525","679600"],"_btv_view_count":["32"],"_bbp_topic_status":["unanswered"]},"test":"valerym-m5gmail-com"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/458386","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/458386\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=458386"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}