Adaptive fuzzy backstepping output feedback control of nonlinear uncertain time-delay systems based on high-gain filters

作者：Li Yongming; Ren Chang'e; Tong Shaocheng^*

来源：Nonlinear Dynamics, 2012, 69(3): 781-792.

DOI：10.1007/s11071-011-0304-z

• Nonlinear strict-feedback systems
• Adaptive fuzzy control
• Output feedback control
• Time-delay
• High-gain filter
• Backstepping technique
• Stability analysis

In this paper, an adaptive fuzzy output feedback control approach is developed for a class of SISO uncertain nonlinear strict-feedback systems. The considered nonlinear systems contain unknown nonlinear functions, unknown time-varying delays and unmeasured states. The fuzzy logic systems are first used to approximate the unknown nonlinear functions, and then a high-gain filter is designed to estimate the unmeasured states. Combining the backstepping recursive design technique and adaptive fuzzy control design, an adaptive fuzzy output feedback backstepping control method is developed. It is proved that the proposed adaptive fuzzy control approach can guarantee that all the signals in the closed-loop system are semi-globally uniformly ultimately bounded (SGUUB) and both the observer error and tracking error converge to a small neighborhood of the origin. Two key advantages of our scheme are that (i) the high-gain filter is designed to estimate unmeasured states of time-delay nonlinear system, and (ii) the virtual control gains are functions. A simulation is included to illustrate the effectiveness of the proposed approach.

• 出版日期2012-8
• 单位辽宁工业大学