Model Reference Adaptive Control with Unknown Gain Sign

Abstract

In this paper, a model reference adaptive control scheme is proposed by using Nussbaum function for first order linear system with unknown gain sign. Only one self-tuning parameter is designed. Based on Lyapunov method, the Nussbaum parameter is determined. Using Nussbaum function, unknown gain sign is handled. According to Babalat’s lemma, the tracking error is proved to converge to zero. A numerical example is provided to demonstrate the effectiveness of the proposed method.