Abstract
In this paper, the H-infinity reliable control problem is investigated for a class of nonlinear singular systems subject to external disturbance and actuator faults and saturations. By means of the Takagi-Sugeno fuzzy model to describe the nonlinear plant, a reliable sliding-mode control scheme is built to compensate for the impact of aforementioned factors on system stability and performance. First, a fuzzy integral sliding function is designed and sufficient conditions are derived such that the sliding-mode dynamics is robustly admissible and satisfies the pre-specified H-infinity disturbance attenuation requirement. Then, by considering the saturation as nonlinear input, an adaptive sliding-mode control law is synthesized to ensure reachability of the specified sliding surface. Finally, the lower-limb rehabilitation system is exploited to validate the effectiveness of the presented controller design methodology.