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BCs for flexbodies

Josef K.
Hello,
 
Is there a way to include SPCs in your model when creating and MNF file for a flexbody? I am asking because when I tried creating an mnf file for a table-like structure, the 1st mode was completely off than when running a simple sol103. The points which were supposed to be constrained were moving freely in the modes (even though I had also included them in ASETS).
 
Is there another way that I can ensure the validity of the constraints when creating an mnf file?
 
Thanks,
 
Josef
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    Hello bruno,
     
    Per the last part of your answer, as far as I know, the modes of an mnf file do not change when it is constrained i.e., since the 1st mode is at 2.9 Hz (in Adams), even though I used fixed joints, it would still remain the same. I have no way of making it change throught Adams.
     
    As far as the MNF file creation is concerned, my problem perhaphs is in the understandning of how the mnf file creation works. When running simple eigenmodes analysis (sol103) constraining the body for it to be in its "final state" leads to its true modes (since in real life, it wouldn't be free-free). So the same should hold true in the mnf file generation. Thatsa why I asked if there was some mistake in the way I constrained the body for the mnf file creation.
     
    I might be mistake from the beginning though. Can you build an MNF file for a flexbody which will not be free-free? Or regardless of where I place constraints, the MNF file will always containt its free-free modes?
     
    Kind regards,
     
    Josef
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    Hello bruno,
     
    Per the last part of your answer, as far as I know, the modes of an mnf file do not change when it is constrained i.e., since the 1st mode is at 2.9 Hz (in Adams), even though I used fixed joints, it would still remain the same. I have no way of making it change throught Adams.
     
    As far as the MNF file creation is concerned, my problem perhaphs is in the understandning of how the mnf file creation works. When running simple eigenmodes analysis (sol103) constraining the body for it to be in its "final state" leads to its true modes (since in real life, it wouldn't be free-free). So the same should hold true in the mnf file generation. Thatsa why I asked if there was some mistake in the way I constrained the body for the mnf file creation.
     
    I might be mistake from the beginning though. Can you build an MNF file for a flexbody which will not be free-free? Or regardless of where I place constraints, the MNF file will always containt its free-free modes?
     
    Kind regards,
     
    Josef
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