Why might a Modal analysis performed on unconstrained assembly not produce six rigid body modes with zero frequency?
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January 25, 2023 at 7:34 am
FAQ
ParticipantIf penalty based contacts are used to tie the parts together, this could introduce artificial stiffness that can affect the free modes. In particular this could affect the three rotational modes. To avoid this try changing the contact formulation to MPC. This should result in six rigid body modes with zero frequency
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