Non-Recursive Adaptive Control Design Methodology for Nonlinear Systems With Mismatched Time-Varying Disturbances
Abstract This paper proposes a non-recursive adaptive control scheme for a class of lower-triangular nonlinear systems with mismatched time-varying disturbances. As a result, an exact tracking control scheme is constructed straightforwardly from the system in a novel non-recursive synthesis manner. Firstly, with the help of higher-order sliding mode observer (HOSMO), the original system is delicately transformed into an equivalent stabilizable system. Then, a non-recursive stabilizer with a simple update mechanism for the dynamic gain can be derived. Subsequently, a rigorous stability analysis shows the theoretical justification of the proposed design framework. New characteristics of the proposed algorithm are mainly twofold: 1) The proposed adaption mechanism could substantially adjust the transient-time performance with the presence of different levels of disturbances. 2) The composite control design procedure is essentially detached with stability analysis, which could largely facilitate practical implementations.
