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SimLab 2025.1| How to view rigid body modes and mass participation factor in normal mode analysis

Hello, I'm new to normal mode analysis. I ran one (no boundaries in this case) and I would like to know where and how to find the mass participation factor.

I have an additional problem: the normal modes analysis with no constraints was to get the first 6 rigid body modes. I realize I couldn't get any translation of the body in the results, just rotations, which I should instead obtain (if I recall correctly from the theory). I even tried using one of the given models (A7_gear_case_mesh), but got the same results: just rotations, no translation. Is there anything wrong in what I'm doing or doesn't the software contemplate calculating zero frequency modes?

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Marc_21384

Hi,

You need to ask for the output of mass participation in the solver setting. Like this:

Once you do, you can find in the out file. Right click on results and open solver log:

Hope this helps.

Kind regards,

Marc Steiger

CA_Hipparcos

Hi Marc!

Thank you so much.

I still have a problem though: I can't get final result modes where it's almost pure translations (like 9.xxxE-01) especially in x and y, whereas this happens with rotations. As I said, I even tried with a couple of models from your learning center, but I have the same issue.

CA_Hipparcos

Is there anything else I need to set in the solver? The approximations seem a little off.

Is there anything I'm missing (even from the theory)?