Decentralized adaptive backstepping control for a class of interconnected nonlinear systems with unknown actuator failures

In this paper, a decentralized adaptive backstepping control scheme is proposed for a class of interconnected nonlinear systems with unknown actuator failures. By introducing a smooth function, some integrable auxiliary signals and a bound estimation approach, the effect of actuator failures is successfully compensated for. The proposed scheme has the following features: (1) the total number of failures is allowed to be infinite; (2) global stability of the overall closed-loop system is achieved without any bound knowledge of uncertainties; (3) all system outputs converge to zero asymptotically regardless of the possibly infinite number of failures and the unknown interactions among subsystems. Simulation results on coupled inverted double pendulums are presented to illustrate the effectiveness of the proposed scheme.