LSTC has been adding additional eigensolution technology to LSDYNA. 
For several years LSDYNA has a Block Shift and Inverted Lanczos Eigensolver 
in both SMP and MPP implementations. But this capability did not cover the 
full spectrum of applications. We have supplemented the Lanczos solver with 
a Power Method solver for implicit mechanic problems using the Inertia Relief 
Feature. As we have been adding unsymmetric modeling features through materials, 
elements, and contact, we have added an eigensolver based on ARPACK for such 
problems. Important applications for the unsymmetric eigensolver is rotational 
dynamics and brake squeal analysis. We have developed an implementation of 
AMLS (Automated Multilevel Substructuring Method) for applications such as NVH 
that want hundred, even thousands, of eigenmodes quickly which are willing to have 
a less accurate solution compared to the Lanczos eigensolver.