Homogeneous domination-based composite adaptive control strategy for perturbed chain of integrators with mismatched disturbances

In this paper, a composite adaptive control law by utilizing the homogeneous domination-based and the disturbance observer-based method is designed to stabilize a class of perturbed nonlinear system. Inspired by the design of homogeneous domination-based approach and adaptive control algorithm with its identification of the uncertain parameters, a series of virtual controllers are elaborately designed in recursive procedures to counteract system nonlinearities and parameter perturbations. Meanwhile, the mismatched disturbances which exist in channels of states, are compensated in a recursive way via a disturbance estimation and compensation method with the recognized parameters. Both the design framework and stability analysis provide a comprehensive idea in practical implementations. Comparative numerical simulation results of a robot arm system verify performances of the proposed method with respect to several investigations.