Stability margins of nonlinear optimal regulators with nonquadratic performance criteria involving cross-weighting terms

In this payer we derive guaranteed gain, sector, and disk margins for nonli near optimal and inverse optimal regulators that minimize a nonlinear-nonqu adratic performance criterion involving cross-weighting terms. Specifically , sufficient conditions that guarantee gain, sector, and disk margins are g iven in terms of the state, control, and cross-weighting nonlinear-nonquadr atic weighting functions. The proposed results provide a generalization of the "meaningful" inverse optimal nonlinear regulator stability margins as w ell as the classical linear-quadratic optimal regulator gain and phase marg ins. (C) 2000 Elsevier Science B.V. All rights reserved.