Aiming at the nonlinear systems where only the output signals can be measured and their unpredictable states are associated with unknown nonlinear functions and affected by external disturbances
this paper proposes an adaptive neural network dynamic surface control method to solve the problem of output feedback tracking of nonlinear systems. First
the state observer based on RBF neural network is built to ensure the observation error can be gradually converged to zero; second
the adaptive output feedback control rule is designed by using dynamic surface technology; finally
using the steepest descent method and selecting the optimal control parameters
the control input and tracking performance are optimized
and hence the workload of control parameter setting is reduced. This method can ensure the semi-global uniform boundedness of all closed-loop signals
and guarantee system output with specified tracking performance through introducing the performance function and tracking error transformation
thus the transition quality of the control system is improved. Simulation results show that the designed state observer can realize accurate estimation of the system signals
the tracking error signal amplitude is controlled less than 0.02
and the input signal amplitude with optimized control parameters is decreased
verifying the effectiveness of the proposed control method.
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