steady-state error can be eliminated by including an integral term in the linear part of the controller (19).

TLDR: In this article, a neural network was proposed for adaptive output feedback control of uncertain nonlinear systems using neural networks and a simple linear observer was introduced to estimate the derivatives of the tracking error.

Abstract: IX. SUMMARY A new approach has been proposed for adaptive output feedback control of uncertain nonlinear systems using neural networks. A simple linear observer was introduced to estimate the derivatives of the tracking error. These estimates are used as inputs to the neural network and in the adaptation laws as an error signal. Ultimate boundedness of all error signals was proven by Lyapunov’s direct method. Simulations of a second-order system illustrated the theoretical results.