Adaptive fuzzy control for MIMO nonlinear systems with unknown dead-zone

In this paper, a fuzzy adaptive control system is investigated for a class of uncertain multi-input multi-output (MIMO) nonlinear systems with both unknown dead-zone and unknown sign of the control gain matrix (i.e. unknown control direction). To deal with the unknown sign of the control gain matrix, the Nussbaum-type function is used. In the designing of the fuzzy adaptive control scheme, we will fully exploit a decomposition property of the control gain matrix. To compensate the effects of the dead-zone, we require neither the knowledge of dead-zone parameters nor the construction of its inverse. Simulation results demonstrate the effectiveness of the approach.