Robustness and perfect tracking with simple adaptive control in nonlinear systems

Abstract

The need to guarantee robustness of adaptive control systems in the presence of disturbances seems to affect the quality of tracking even in ideal environments. A recent paper revisited and modified the use of various components of the simple adaptive control (SAC) approach of linear time-invariant (LTI) systems and showed how one can use passivity concepts such that, while it maintains robustness with disturbances, it also allows asymptotically perfect tracking in ideal conditions.
Using the extension of passivity conditions to nonstationary systems, this paper extends the analysis of robustness with disturbances and asymptotically perfect tracking in ideal conditions to nonstationary and nonlinear systems.