Active fault-tolerant control for strict-feedback nonlinear systems with prescribed performance

Active fault-tolerant control (AFTC) for strict-feedback nonlinear systems with prescribed performance is investigated in the paper. First a norminal backstepping controller with prescribed performance is presented, which guarantees that the output tracking error is bounded by a predefined function. Secondly, in the presence of unknown faults, an active fault tolerant controller is designed on the basis of fault function approximated by neural network. Both control laws are derived based on Lyapunov stability theory. In each case, the state trajectories of the closed loop system are bounded and the prescribed transient performance for the output tracking error can be achieved. Finally, simulation results show the effectiveness of the proposed approach.