Document Type : Research Articles

Authors

1 Department of Electrical Engineering, Ferdowsi University of Mashhad, Mashhad, Iran

2 Ferdowsi University of Mashhad

3 Electrical department, Faculty of Engineering, Ferdowsi University of Mashhad

4 Department of Electrical Engineering, Mashhad Branch, Islamic Azad University, Mashhad, Iran

Abstract

The robust adaptive leader-follower formation control of uncertain unmanned surface vehicles (USVs) subject to stochastic environmental loads is investigated in this paper. The stochastic additive noises are included in the kinematics which stands for the un-modeled dynamics and uncertainty. The disturbances induced by waves, wind and ocean currents in the kinetics are also separated into deterministic and stochastic components. A comprehensive model including kinematics and kinetics of each USV agent is then derived as stochastic differential equations including standard Wiener processes. Thus, the problem formulation is much more challenging and practical since both the exogenous disturbances and kinematics states are defined by stochastic differential equations. In order to guarantee that all the tracking errors converge to a ball centered at the origin in probability, quartic Lyapunov functions synthesis, dynamic surface control (DSC) technique, the projection algorithm, and neural networks (NNs) are employed. Finally, the simulation experiments quantify the effectiveness of proposed approach.

Keywords