SofimshA Kinematic Constraints

Hello,

Does anybody knows if it is possible to create Kinematic Constraints between the nodes of two edges using sofimshA ?

In the manualul, I saw that it is possible to create a Kinematic Constraint node by node (NODE x FIX KL NR1 y). This method doesn’t work for me because I don’t know the number of the intermediate nodes. So I would like to select directly the sequence of nodes (using FIT maybe ?)

Thank you.

Hello,

Why don’t you use SOFIMSHC and SLN FIX for this? What is the reason you want to use SOFIMSHA and have no control over the number of the (intermediate) nodes?

I’ve already made the model with Sofiplus. But if I put the constraints directly in Sofiplus or sofimshC the genereted mesh becomes very very messy. So, I prefer to generate the mesh with Sofiplus without constraints in order to obtain a good mesh and add the constraints afterwords with sofimshA.

In this case, why not write down the number of the structure lines and add the constrain subsequently with SOFIMSHC, not SOFIMSHA? If you give a negative value for SLN NO, you can modify an existing line. For example with

+PROG SOFIMSHC
SYST REST
CTRL MESH 2
SLN NO -1 FIX F->2
END

you add boundary condition to existing structure line 1.
But the meshing will still be “messy” as the module will likely add some nodes.

What happens if you define the structure lines in SOFIPLUS with a given mesh density? Or if you adapt the meshing density of the structure areas?

Thank you for your answers.
Yes. The mesh will still be messy.

With the workflow you have choosen there is no other way than getting to know number of nodes either manually or with somekind of script and then apply constraints to single nodes.

If you know the coordinates of the intersection nodes, you can get the nodenumbers with GETN.
(But it may be better to define the number of important nodes in advance.)

Finally, I defined the extreme nodes of the edges and I used this code line in sofimshA

node fit «a» «b» fix KF nr1 fit «c» «d» 

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