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Making a shell edge "couple" with rigid frame

Making a shell edge "couple" with rigid frame

Making a shell edge "couple" with rigid frame

(OP)
Good afternoon, I'm trying to have a shell behave as a rigid in its edges, so i creatade a "frame" composed by 4 rigid bars that move, and want to make a shell have that motion, however I am having trouble coupling both , because when I try and do that it generates problems in the corners ( of the edge i assume) because they are assigned twice, since each corner is shared by two edges. Would like to know if you have any sugestions.

I've attached a picture of the rigid frame "displaced" and the shell.
Thank you for your time.

RE: Making a shell edge "couple" with rigid frame

The image is not working.

I assume you tie the shell nodes to the rigid bars an get trouble at the corners, where a node cannot be tied to two bars.

When the rotation point is equal to the corner node, then it doesn't matter where the node is tied to. Choose one of the bars.
And I think in reality you should have that rotation point there, otherwise you would directly rip the shell apart.

RE: Making a shell edge "couple" with rigid frame

(OP)
Thanks for the response. I think I understand your response, but my problem is that the goal of the test is to obtain pure shear, so it demands the shell being constrained in all 4 edges and those edges moving/rotating but not to happen axial deformation, which happens always if i only couple rotation.
I have seen literature that refers to pin joint in the nodes of the shell, but I can't seem to do it, due to only having 1 node in each corner, and so Im no able to atribute multi-point constraints as refered in this paper i read. I can leave here the place where they explain what they did, because i can't make sense of it. Probably this is a very simple task, but I can't wrap my head around it.

"Pin joint consists of two co-incident nodes tied in a multi-point constraint at the four corners of the panel. The displacements of the dependent node is made the same as that of the independent node, but the rotations of the co-incident nodes are excluded in the nmlti-point constraints."

Thanks for your time.

RE: Making a shell edge "couple" with rigid frame

You can use the PIN option in the rigid body to have the rotation unconstrained.

You can also try to use the separate TIE constraint for the connection of the shell to the bars. Here you can uncheck the option, that the rotations are also tied.

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