Non‐Identification Adaptive Control for Large‐Scale Nonlinear Systems With Uncertain Measurement Sensitivity

This article is concerned with the issue of the decentralized output feedback control for large‐scale nonlinear systems with measurement uncertainty via non‐identification adaptive technique. Generalized Lyapunov inequations based two dual‐scaling adaptive control methods are proposed, which are applicable to lower/upper‐triangular large‐scale nonlinear systems with large measurement uncertainty, respectively. Particularly, the uncertain measurement sensitivity is allowed to vary within a positive interval and to be non‐differentiable. Resorting to the dual‐domination idea, global state regulation is achieved by adaptive output feedback. Specifically, for lower‐triangular growth interconnected nonlinear systems with output‐polynomial growth constraint, a couple of high‐dynamic‐gain observer and controller are presented. In contrast, a low‐dynamic‐gain control scheme is proposed for a class of upper‐triangular growth large‐scale systems with interconnected nonlinearities satisfying input‐dependent growth condition. Notably, the proposed control schemes are both non‐backstepping, and all design parameters are given by explicit constraint inequations.