{"id":38579,"date":"2019-10-26T19:45:21","date_gmt":"2019-10-26T19:45:21","guid":{"rendered":"\/forum\/forums\/topic\/nonlinear-revolute-joint-rotational-stiffness\/"},"modified":"2019-10-26T19:45:21","modified_gmt":"2019-10-26T19:45:21","slug":"nonlinear-revolute-joint-rotational-stiffness","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/nonlinear-revolute-joint-rotational-stiffness\/","title":{"rendered":"Nonlinear Revolute Joint Rotational Stiffness"},"content":{"rendered":"<p>Hi there,<\/p>\n<p><\/p>\n<p>I need to model nonlinear rotational stiffness in a revolute joint to simulate the joint yielding, ie once the joint begins to yield the stiffness of it will decrease, similar to the following:<\/p>\n<p><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/us.v-cdn.net\/6032193\/uploads\/attachments\/3fa28c7a-0cd9-496d-91a9-aaf2013c7c7a\/43b23e31-9ffa-44e7-9ba2-aaf20143486a_capture.jpg?width=690&amp;upscale=false\" alt=\"\"><\/p>\n<p><\/p>\n<p>I am using ANSYS Workbench Mechanical 2019 R2 with a Static Structural analysis.&nbsp;I see the torsional stiffness option is given in units of [Nmm\/degree], which would only represent the Ki section of the above graph. My question is, can you use tabular data, or a command to get the nonlinear plot of above?<\/p>\n<p><\/p>\n<p>Note I am new to commands in Workbench, and have tried the following with no success:<\/p>\n<p><\/p>\n<p>Simple beam model with fixed ends, one revolute joint connecting the beams between end vertices, and gravity load:<\/p>\n<p><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/us.v-cdn.net\/6032193\/uploads\/attachments\/3fa28c7a-0cd9-496d-91a9-aaf2013c7c7a\/56c2b09e-1f75-4eaa-9b29-aaf20142598c_capture.jpg?width=690&amp;upscale=false\" alt=\"\"><\/p>\n<p><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/us.v-cdn.net\/6032193\/uploads\/attachments\/3fa28c7a-0cd9-496d-91a9-aaf2013c7c7a\/4e4c6d8e-fdbd-46be-949d-aaf2014480f1_capture.jpg?width=690&amp;upscale=false\" alt=\"\"><\/p>\n<p><\/p>\n<p>Trying the following command to create tabular data of rotation behavior [degrees] and the corresponding moment [Nmm] with the intention that this is the moment stiffness of the joint will follow when deforming&nbsp;(note the values are arbitrary and not representative of the bi-linear graph).&nbsp;<\/p>\n<p><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/us.v-cdn.net\/6032193\/uploads\/attachments\/3fa28c7a-0cd9-496d-91a9-aaf2013c7c7a\/cb7afcf0-6680-40d3-9909-aaf201408063_capture.jpg?width=690&amp;upscale=false\" alt=\"\"><\/p>\n<p><\/p>\n<p>This command appears to apply a moment to the joint, whereas I want the joint to change stiffness as the joint deforms:<\/p>\n<p><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/us.v-cdn.net\/6032193\/uploads\/attachments\/3fa28c7a-0cd9-496d-91a9-aaf2013c7c7a\/06395125-a378-43d6-a23b-aaf20140fe3d_capture.jpg?width=690&amp;upscale=false\" alt=\"\"><\/p>\n<p><\/p>\n<p>Any help would be much appreciated, and it would be good to know if you can extend this to more degrees of rotational freedom, ie also about the y-axis.<\/p>\n","protected":false},"template":"","class_list":["post-38579","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_old_topic_id":["10757"],"_bbp_old_topic_author_name_id":["Anonymous"],"_bbp_old_is_topic_anonymous_id":["false"],"_bbp_old_closed_status_id":["publish"],"_bbp_author_ip":[null],"_bbp_old_sticky_status_id":["normal"],"_bbp_likes_count":["0"],"_btv_view_count":["2579"],"_bbp_subscription":["244264"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["38579"],"_bbp_forum_id":["27791"],"_bbp_engagement":["240","169890","182190"],"_bbp_voice_count":["3"],"_bbp_reply_count":["4"],"_bbp_last_reply_id":["129600"],"_bbp_last_active_id":["129600"],"_bbp_last_active_time":["2020-10-13 02:13:23"]},"test":"leoansys"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/38579","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\/38579\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=38579"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}