Stability criteria for nonclassically damped systems with nonlinear uncertainties

The asymptotic stability of nonclassically damped systems with nonlinear uncertainties is addressed using the Lyapunov approach. Bounds on nonlinear perturbations that maintain the stability of an asymptotically stable, linear multi-degree-of-freedom system with nonclassical damping are derived. The explicit nature of the construction permits us to directly express the algebraic criteria in terms of plant parameters. The results are then applied to the symmetric output feedback control of multi-degree-of-freedom systems with nonlinear uncertainties. Numerical examples are given to demonstrate the new stability criteria and to compare them with the previous results in the literature.