I made a simple test model (3 versions - *RIGID BODY, *COUPLING with *DISTRIBUTING and *DISTRIBUTING COUPLING) in Abaqus. It all works as expected there but not in CalculiX (rigid body fails with no errors, couplings complete but the results are wrong). Apparently, there are some issues with *EQUATION used on reference nodes. Perhaps we should use a spring or beam instead.
ah i’m not aware since plot result shown symmetric, model is restrained for out of plane movement. Actually, this problem can be simplified without contact nonlinearity and large deformation activated.
use contact type tied and set friction to lowest enough, deactivated Nlgeom for linear analysis. However, implementing hinge connection in PrePoMax could be a useful feature.
This could be another option to explore. It’s able to follow large displacements and variations of the hinge axis. No pin. It involves *MPC custom cards.
*MPC
STRAIGHT,77,182,57,62,67,72,187,192,197,202
*MPC
BEAM,77,182
Hi, I also have had problems representing hinges but I thought they depended on my lack of proficiency with Calculix. I’m honestly very surprised such simple concept requires so elaborated a procedure. What about simply creating two ref. nodes and joining them through a rigid body which releases rotation ? I understand ref. nodes cannot be joined but why? What’s the obstacle ? This is the normal way to do it. Creating an equation is crazily complicated. Using the pin is a bit silly but practically the only way inasmuch as I can tell. Is this a deficiency of Calculix ?