An observer-based approach to adaptive tracking for switched strict-feedback nonlinear systems with state quantization and sensor faults

This paper investigates the adaptive tracking problems of switched single-input single-output strict-feedback nonlinear systems with state quantization and sensor faults. In order to alleviate the influence of the potential sensor faults and smooth the discontinuous quantized signals, a state observer is established. Then, an observer-based adaptive quantized fault-tolerant controller is designed by introducing a set of new error variables. It is shown that the presented approach can enable the output tracking error to be arbitrarily small. At last, three examples are given to illustrate the effectiveness of the presented method.