{"id":55050,"date":"2017-10-11T20:59:15","date_gmt":"2017-10-11T20:59:15","guid":{"rendered":"\/forum\/forums\/reply\/55050\/"},"modified":"2017-10-11T20:59:15","modified_gmt":"2017-10-11T20:59:15","slug":"55050","status":"publish","type":"reply","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/55050\/","title":{"rendered":"Reply To: Force frictional sliding contact behavior in RBD ?"},"content":{"rendered":"

Force Frictional Sliding contact is not designed to model sticking situation.<\/span>It works well for sliding contact where the friction leads to a resisting force (opposed to the sliding velocity) which is directly proportional to the normal contact force Ft=mu<\/span>Fn. <\/em><\/p>\n

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In order to avoid integration difficulty with low sliding velocities (basically when the contact would ideally be sticking or close to sticking), the friction factor varies linearly between 0 and its nominal values if the sliding velocity is lower than a given velocity. <\/em><\/p>\n

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In summary, If ||v||>=v_tol, Ft=mu<\/em>Fn If ||v||<\/span><vtol, Ft=mu*(||v||\/vtol)*Fn This velocity tolerance is internally computed from the contact radius among many other parameters. <\/em><\/p>\n

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Unfortunately, this tolerance cannot be get or set by the user. However, there is a command that affects its computation. options=CS_SolverOptions() options.VelocityToleranceFactor=1.0 The default value is 100. It allows to improve the behavior to be “closer” to a sticking contact but it won’t ever be perfectly sticking. <\/em><\/p>\n

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With a factor=1 (a lower velocity tolerance), it will be possible to have lower sliding velocities, like an “almost sticking” contact status.<\/em><\/p>\n","protected":false},"template":"","class_list":["post-55050","reply","type-reply","status-publish","hentry"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t