Odd results in my Modal analysis??

[rubenwood]

Hi there,

I am working on a large lighting feature for a boat and have to be carefull with the dynamic frequencies. I have made the model and run the modal analysis and i am getting some unacceptable frequencies, however in the result I am getting a 0% Cur.mas in all directions? See below: 

Now following the old cliche if it looks wrong it probably is wrong I am doubtful. However the the movement in the model is bizarre too, it is almost torsional, I have attached the exagerrated deflected shape and the original below.

Is there something wrong with my analysis or is it possible to get 0% mass movement in all directions?

Thanks

[Artur.Kosakowski]

It is possible for antisymmetric shape of torsional vibrations.

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