Physics

Control engineering

Nonlinear system

Mathematics

Feed forward

Agronomy

Backstepping

Biology

Underactuation

Gene

Adaptive control

Engineering

Mathematical analysis

Artificial intelligence

Singularity

Controller (irrigation)

Control (management)

Chemistry

Computer science

Quantum mechanics

Control theory (sociology)

Artificial neural network

Biochemistry

Lyapunov function

Robustness (evolution)

IEEE Transactions on Neural Networks and Learning Systems

This paper presents adaptive neural tracking control of underactuated surface vessels with modeling uncertainties and time-varying external disturbances, where the tracking errors consisting of position and orientation errors are required to keep inside their predefined feasible regions in which the controller singularity problem does not happen. To provide the preselected specifications on the transient and steady-state performances of the tracking errors, the boundary functions of the predefined regions are taken as exponentially decaying functions of time. The unknown external disturbances are estimated by disturbance observers and then are compensated in the feedforward control loop to improve the robustness against the disturbances. Based on the dynamic surface control technique, backstepping procedure, logarithmic barrier functions, and control Lyapunov synthesis, singularity-free controllers are presented to guarantee the satisfaction of predefined performance requirements. In addition to the nominal case when the accurate model of a marine vessel is known a priori, the modeling uncertainties in the form of unknown nonlinear functions are also discussed. Adaptive neural control with the compensations of modeling uncertainties and external disturbances is developed to achieve the boundedness of the signals in the closed-loop system with guaranteed transient and steady-state tracking performances. Simulation results show the performance of the vessel control systems.

Adaptive Neural Control of Underactuated Surface Vessels With Prescribed Performance Guarantees