Adaptive Control of Switched Nonlinear Systems with Unknown Control Directions

This paper investigates the adaptive output feedback control problem of a class of switched non-strict feedback nonlinear systems with unmeasurable states, and unknown control gain functions with unknown signs. Without employing the Nussbaum function approach, an adaptive control method is proposed using a different error surface in dynamic surface control. The proposed control scheme ensures that all the closed-loop signals remain bounded under arbitrary switching. The simulation results clarify the effectiveness of the proposed technique.