Output tracker design for uncertain nonlinear sandwich systems with sandwiched dead-zone nonlinearity based on adaptive finite-time control

This paper addresses the adaptive finite-time tracking problem for nonlinear sandwich systems with dead-zone nonlinearity and full state constraints. The existence of the non-smooth dead-zone nonlinearity between the subsystems of the sandwich system makes the controller design as a challenging task. In this paper, a novel adaptive backstepping controller is proposed by employing the finite-time stability theorem and based on the barrier Lyapunov functions and finite-time command filters. The proposed controller guarantees the output tracking of the specified time-varying reference signal with the sufficiently small bounded tracking error in a finite-time. Moreover, all states of the controlled system are confined to predefined compact sets. To verify the theoretical achievements and show the applicability of the proposed method, simulation results are provided for both numerical and practical examples.