Karamba issue

Hello, I have a problem and couldn’t find anything useful.

The problem is this:

  1. There are 157 rigid body modes in the system. This means some parts can move freely without causing deformation.
    Try to use the ‘Eigen Modes’-component and activate the display of local coordinate axes: The first eigen-mode will be the rigid body motion.
    If this does not help, check whether you have a pinned support directly attached to a hinge. A hinge introduces an extra node which may cause the problem.
    When analyzing a flat shell structure one has to lock the rotation perpendicular to the plate in at least one node.

I saw that they recommended using “Connected Parts (Karamba3D)” or "Eigen Modes (Karamba3D), but it seems like I have only one branch on my list.
I hope you can help me with it:)
karamba.gh (99.5 KB)
20.12.3dm (468.2 KB)

Hi,
it seems to me that the problem is the structural stability itself.
You modified all the elements as to be “truss”, right?.
Part of the structure has rectangular geometry which makes it unstable.

If you change their properties to “Frame”, there would be no “rigid-body modes”.

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