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Error #723

Dani_20

Hello,

I am trying to perform a monocoque analysis with the suspensions system included. I follow the next steps:

- I have introduced the nodes of each point and I have joined it with lines.

- Then I have meshed the lines in an independent component with line mesh option

- I have created nodes in monocoque holes (Where would be the attachment)

- I have created a rigid (RBE2) between the bar and monocoque nodes

- I have created a rigid (RBE2) between monocoque nodes and surrounding nodes

- I have created a load on the monocoque and a constraint at the end of the suspension bar

In the picture below, it can be seen the suspension modelation (There are some missing nodes due to visualitation problem)

image.png.2ecd4497ffabd6ad3ae3372601c79ed4.png

After that, I have tried to simulate and the following error appear:

*** ERROR # 723 ***
An invalid rigid element.
This RBE2 is not connected with any structural element.
RBE2 element id = 1041945
independent grid id = 1040450
Note: If this rigid element is also connected with other rigid elements,
then this error means that there is rigid body mode or mechanism remained
in this rigid element chain due to lack of connected structural elements.

Could anybody help me please?

Thank you

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Rahul Rajan_21763

The one or both ends of the rigid element is/are not connected to any node(s) associated with the structural element. This causes one or more ends of the RBE2 element to be free.

Suggestions for Resolution:

Check for any rigid elements or rigid element chains with ends that are not connected to any grid point (nodes) associated with structural element.

Also apply 1d checks(F10:1d )

Robert Lawson

Are you sure when you did your line mesh, you got actually got structural elements? Your picture above doesn't show any bars, beams or rods on those lines.

Your pink rigids connecting to the green structure appear to just be connecting to single nodes on the green. That's likely going to result in some unrealistic stresses and deformation there. You'll likely need to grab a bigger footprint there.

Dani_20

The one or both ends of the rigid element is/are not connected to any node(s) associated with the structural element. This causes one or more ends of the RBE2 element to be free.

Suggestions for Resolution:

Check for any rigid elements or rigid element chains with ends that are not connected to any grid point (nodes) associated with structural element.

Also apply 1d checks(F10:1d )

Problem solve it, I have check and repair the wrong connections. Thank for you support.

Robert, the mesh is not showed in this picture but is there. The nodes are also connected to the green structure with more than one node, but is not visible in the picture. Anyway thanks for you reply