IJCAS

In this paper, a class of nonlinear systems with sensor faults and uncertainty problem are considered. The proposed control scheme is designed based on backstepping procedure. Additionally, three classes of filters are introduced, a serious of K-filters and an auxiliary filter are used to deal with the unmeasurable system states, and the command filters are adopted to avoid the “differential explosion” problem in backstepping design. Furthermore, the bound estimation method is adopted to estimate the unknown system parameters, partial loss fault of sensor and the upper bound of unknown nonlinear functions. Meanwhile, the proposed scheme reduces the amount of calculations in the controller design and and plays a certain role in saving network resources. Even when the sensor fails, the proposed scheme can ensure that all the signals in the closed-loop system are uniformly and ultimately bounded. Finally, a single-link robot arm example is simulated to show the feasibility of the proposed scheme.

Keywords: Adaptive backstepping, command filtering technique, event-triggered control, fault-tolerant control, K-filters, output feedback control.