Event-triggered adaptive finite time trajectory tracking control for an underactuated vessel considering unknown time-varying disturbances
Qiwen Wang, Qiang Zhang, Yugang Wang, Yancai Hu, Shaoyi Guo
Abstract
Abstract This paper aims to solve the finite-time trajectory tracking problem of underactuated surface ships under the influence of dynamic uncertainty, unknown external time-varying interference and limited communication resources. An event-triggered robust adaptive finite-time trajectory tracking control method for underactuated ships is designed by combining the existing trajectory tracking control methods and engineering needs in actual navigation. It can obviously improve the tracking accuracy of the ship, and complete the tracking task safely and efficiently. This scheme transforms the composite uncertain vector synthesized by uncertain parameters and external disturbances into a linear parameterized form. Next, considering the limitation of communication resources, a relative threshold event triggering mechanism is introduced to further extend the triggering time interval on the basis of the fixed threshold triggering scheme. Then, an event-triggered robust adaptive finite-time trajectory tracking control scheme is designed for underactuated ships, and a rigorous stability proof is provided through Lyapunov stability theory. Simulation experiment is carried out in MATLAB and the results show that the finite-time trajectory tracking control scheme proposed in this paper can effectively solve the problems of dynamic uncertainty, unknown time-varying external interference and limitation of communication resources. This paper can provide theoretical support for the autonomous navigation of intelligent ships.