I need to include the bending mode dynamics in my simulation. So far, I am only considering the rigid body dynamics. So I need to implement the following equation:

q'' + Kg*q = Phi*F(t), where:

• q is the generalized coordinates;
• Phi = Mode Shape Matrix,
• Kg = Generalized Stiffness Matrix;
• Force;

As far I understand I need the modal shape matrix, which is built from the eigenvector associated to eigenvalues to applied the force at generalized coordinates and to retrieve the physical displacement from:

x = Phi*q(t)

where x is the physical coordinate.

I have asked a friend to model the object at Nastran and I got the results from .fd6 file.

It has the Generalizes Stiffness Matrix (and the values are the same of eigenvalues), but I could not find the Modal shape Matrix.

So my question is, do I have to construct the model shape matrix based on each eigenvector associated to eigenvalues or it can be obtained from another way at Nastran?

Thank you in advance.