Hello,
I need to extract the System Matrices K (stiffness) M (mass) and D (damping) of an optistruct model. I know I can do it with PARAM,EXTOUT,DMIGPCH and the definition of an ASET1. To obtain the complete matrices, I wa ssimply adding all nodes to the ASET1. It works but I have the following Problem:
When I solve the Eigenvalue Problem with the obtained Matrices, I am missing the 6 rigid body modes. Probably because the ASET1 is a boundary set which means no RBMs.
Do I have any Option to obtain the full Matrices including the rigid Body modes?
Thank you in advance,
Gesa Popesa
