Adaptive predefined‐time tracking control for high‐order strict‐feedback nonlinear systems with unknown mismatched disturbances

Summary The problem of practical predefined‐time tracking control is con sidered for high‐order strict‐feedback nonlinear systems subject to unknown mismatched disturbances. The exact bound of the mismatched disturbances is unknown in this study. A novel adaptive predefined‐time tracking control strategy based on backstepping is proposed by applying a predefined time stability theory. Using the designed tracking controller, all signals are bounded, and a user‐defined bound on the tracking error is ensured in a predefined interval, independent of initial states. The estimation parameters associated with the upper bound of the disturbances are updated adaptively, making the system robust to the disturbances. Simulation studies are conducted to illustrate the performance of the proposed control strategy.