Predefined-time Fuzzy Output Feedback Control for Nonlinear Systems with Multiple Actuator Constraints

In this paper, a predefined-time adaptive fuzzy tracking control method is proposed for uncertain nonlinear systems with multiple actuator constraints and external disturbances. The unknown dynamic part of the system is dealt with by means of the fuzzy approximation theory, and the unmeasured state in the system is approximated by the constructed fuzzy state observer. On the basis of the observer, a novel predefined-time control scheme is developed to ensure that the system can achieve the practical predefined time stable (PPTS). Combined with the stability analysis, the virtual control input with predefined time can be obtained, and its derivative can be estimated by the first-order filter. Theoretical analysis shows that the proposed controller achieves a small residual set of error convergence to the origin in a predefined time. Finally, the feasibility of the theoretical results is demonstrated through simulation examples.