Modal shapes

Modal Shapes

To plot Modal shapes, you must:

• Have at least one observer variable (which may, or may not be a state observer),

• Have at least one free state (state observers count as free states) so that you have at least one eigenvalue,

• Do the linearization in an equilibrium position.

If you break the first two rules, Simcenter Amesim will stop you. The third rule is your entire responsibility.

You proceed by selecting a particular eigenvalue. Note that:

• this implies a particular frequency that is a characteristic frequency of the system.

• the plot will show how each observer variable responds to a small disturbance of this frequency.