Adaptive control for Hammerstein systems with dead-zone nonlinearity and bounded noise

Abstract

This note focuses on robust adaptive controller design for Hammerstein systems with symmetric dead-zone nonlinearity and bounded noise. A modified control law is proposed to compensate dead-zone nonlinearity and a new recursive estimator with a nonnegative data weighting is presented to deal with bounded noise. From convergence properties and global stability analysis, we show that parameter estimation is convergent and the closed-loop system is globally stable. What is more, the theoretical results also show that tracking error is convergent with a specific residue which is related to parameter estimation and the upper bound of noise.