Adams Natural Frequency

hello,everyone
I use the adams2013 to simulate the test11 for the linearation,I get the natural frequency table:natural.txt (52.7 KB) There are hundreds of natural frequency.
I don’t know how to get the natural frequecy just like FAST did (just 24 DOF) and get the system shape in every frequency(24 DOF).
Hope your help!
BEST REGARD!
Ruiliang.Wang

Dear Ruiliang,

An MSC.ADAMS model typically has many more DOFs than an equivalent FAST model, so, more natural frequencies are expected from an MSC.ADAMS model.

You can visualize the mode shapes from an ADAMS linearization analysis in ADAMS View. The numerical solution of the eigenvalues/eigenvectors is contained in the *.out ADAMS output (albeit not in a very easy-to-use form).

Best regards,

Dear Jason
I want to compare the natural frequency between the ADAMS and FAST.IThere are so many frequency in ADAMS ,I need how to choose the natural frequecy or get the desired natural frequency from adams.

BEST
Ruiliang.Wang

Dear Ruiliang,

Yes, you should match the equivalent full-system natural frequencies between FAST and ADAMS. This requires interpreting the modes calculated by the FAST and ADAMS eigensolutions.

Best regards,