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COSMOS Beam element

COSMOS Beam element

COSMOS Beam element

(OP)
I am trying to analyze a beam element tube frame vehicle chassis model in COSMOS using the beam element analysis. I am running into issues with Cosmos telling me that "PCG Iterative solver stopped. Status Code 2: Preconditioner_fails_to_factor. May not have sufficient restraints. No results saved"

I have been trying to test the frame using multiple methods. The test work when I assign all tubes as beams (not trusses) with fixed ends. Once I attempt to input my suspension components as either trusses or beams with pins at either end this message appears.

I know I have sufficiently constrained the model as I have added 4 fixed points to the rear of the chassis, and applied my torsion loads to the front hubs.

What is causing this issue and how can I solve it?

Thank You

RE: COSMOS Beam element

First, Try using the DIRECT SPARSE solver instead of the this FFE solver.
If problem still occurs, Check the .OUT file and see which NODE or ELEMENT is problematic.

RE: COSMOS Beam element

(OP)
I tried the direct sparse solver and that did not work, it gave me another error. I have been looking in the .out files but it does not have a line that references what node was giving me an issue or matrix diagonal. It states what the error was, number of nodes, and what options I had, but that is it. Is there another error log file I can view? The error I get is "stiffness matrix diagonal is 0 at equation 125"

I tried to use a soft spring to stabilize the model and inertial relief and I get a solution, but a very unrealistic one. It also pops up with a large displacement warning. I will see if perhaps adding the steering tie rod will help stabilize the system. Any other ideas?

RE: COSMOS Beam element

(OP)
I tried the steering tie rod and now I get a new error, that says "excessive reverse offsets at two ends of beam". Any ideas of what that means?
Here are some pictures of what my current setup is:

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