Assigning a reference point to a rigid part in ABAQUS

[TennisGuy543]

hello,

I am running a simulation in which one of the parts is a rigid body. I have a quick question regarding the defining of reference points. Basically, when I try to run my job, I get an error message saying "The rigid part instance Part-4-1 is missing a reference point".

It makes sense that a rigid body needs a reference point, so I go back and define a reference point by clicking Tools, then Reference Point, then clicking a vertex on the rigid body. The viewport then labels that reference point as "RP-2" (I have another reference point located elsewhere in the assembly). However, when I run the job again, I get the same error message that I displayed above. I am baffled because this should be a simple procedure to assign a reference point to a part instance, but clearly I have not yet assigned a reference point to that part.

Am I doing something wrong? Is there a different way to assign a reference point to a given part?


I would greatly appreciate any help. Thanks!

 

[IceBreakerSours]

You create a reference point but you forgot to "assign" RP-2 as the reference node for the rigid body.

http://www.eng-tips.com/faqs.cfm?fid=376

http://www.eng-tips.com/faqs.cfm?fid=1083

 

[corus]

I can't see what you've done wrong here as you seem to have assigned the ref point. To be certain, you should see the ref point on the part in the part module, and again in the Assembly module. Just make sure you assigned it to the rigid part and not to some other part you have.

 

[Nitemech]

Can I ask a question regarding rigid bodies as i am also having some problems with this. Can somebody please explain the difference between a rigid body with a reference point and the rigid body constraint in the interaction module. Is the rigid body supposed to have a rigid body constraint or is the rigid body constraint meant for deformable bodies? Just a bit confused:/ Thanks.

 

[Nitemech]

Also, I get an error message when running the analysis that there is "zero pivot when processing D.O.F of 1 nodes". This node is the reference point that i put on the rigid body. Does anyone know how this can be fixed?

 

[IceBreakerSours]

In case you have not, I suggest reading the documentation. Answers to your questions are in it.

In all probability, the rigid body reference node is either free to translate or rotate (or both), *unless* the zero pivot message is due to an overconstraint which the ABAQUS pre-processor decides to release (yes, that can happen) thereby causing the node to be free to translate/rotate.

http://www.eng-tips.com/faqs.cfm?fid=376

http://www.eng-tips.com/faqs.cfm?fid=1083