×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Kinematic coupling error

Kinematic coupling error

Kinematic coupling error

(OP)
Hello everyone,

I'm having an issue with one of my Abaqus models.
I have one model (circular beam), which I can change the coupling constraints from distributing to kinematic without any problems.

Then I have a second model, whose script I made on the basis of the first one. Now I get this error when I go from distributing to kinematic:

***ERROR: DEGREE OF FREEDOM 1 DOES NOT EXIST FOR NODE 2706 INSTANCE
FOILHALF-BOTTOM. IT HAS ALREADY BEEN ELIMINATED BY ANOTHER EQUATION,
MPC, RIGID BODY, KINEMATIC COUPLING CONSTRAINT, TIE CONSTRAINT OR
EMBEDDED ELEMENT CONSTRAINT. THE KINEMATIC COUPLING CONSTRAINT
CANNOT BE FORMED.

and also for the rest of the DOFs. I've attached the two scripts.

First one: circle_crack_3dmodel_master.inp (uses circle_crack_3dmodel.inp and circle_crack_fromhm.inp)
http://files.engineering.com/getfile.aspx?folder=c...
http://files.engineering.com/getfile.aspx?folder=d...
http://files.engineering.com/getfile.aspx?folder=8...

Second one: foil_crack_3dmodel_master.inp (uses foil_crack_3dmodel.inp and foil_crack_3dmodel_sets.inp)
The coupling constraint is located in foil_crack_3dmodel.inp
http://files.engineering.com/getfile.aspx?folder=8...
http://files.engineering.com/getfile.aspx?folder=3...
http://files.engineering.com/getfile.aspx?folder=4...


Can anybody help me?

Thanks a lot, Christian

RE: Kinematic coupling error

Your Coupling Reference Node is at same time also in the region that is coupled to the Ref Node, so he is master and slave at the same time. That's not possible. The easiest solution is to make a separate Ref Node.

RE: Kinematic coupling error

(OP)
Thanks a lot!
Can I ask why it works for my first model then?

RE: Kinematic coupling error

Probably because you used a distributed coupling here and this does not eliminate DOFs at nodes.

RE: Kinematic coupling error

(OP)
But I can straight away change the coupling to kinematic and it will run with no errors.
The thing is I have to run all my load cases for both distributing and kinematic coupling.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources