Decentralized model reference adaptive control for interconnected systems with time-varying delays and unknown dead-zone inputs

In this study, the decentralized model reference adaptive control (DMRAC) problem is tackled for a class of time-varying delay interconnect systems that comprise unknown system matrices and unknown dead-zone inputs. Two robust adaptive control methods are proposed for state tracking based on the moderate matching time-varying delay nonlinear assumptions and the matching between the controlled system and reference model matrices, respectively. The control gain function is explicitly expressed, and it is applied to the adaptive law gains simultaneously. Moreover, a Lyapunov-Krasovskii functional with two integral functions is developed. Besides the properties of the type-B Nussbaum function, the circumstance where the system parameters are fully unknown is considered. As indicated by the results, all signals in the closed-loop system are bounded while fulfilling asymptotically tracked control objectives. The simulation example of this study verifies the effectiveness and feasibility of the proposed design method.