Finite-time extended state observer-based distributed formation control for marine surface vehicles with input saturation and disturbances

This paper investigates the finite-time extended state observer-based distributed formation control for marine surface vehicles with input saturation and external disturbances. Initially, a novel finite-time extended state observer is proposed to estimate the unavailable velocity measurements and external disturbances simultaneously. No longer regarding the time derivative of external disturbances as zero, the proposed finite-time extended state observer is designed by transforming the disturbances as an extended state of the system to be estimated. Then, based on the estimated values, a distributed finite-time formation controller is designed for a group of marine surface vehicles to track a time-varying virtual leader. The position state of virtual leader only can be accessed by a subset of the group members. Furthermore, a saturation function is incorporated into the controller to solve the input saturation problem. Finally, a rigorous Proof demonstrates that the finite-time stability of the proposed extended state observer and formation controller can be guaranteed by using homogeneous method and Lyapunov theory. Numerical simulations illustrate the effectiveness of the proposed formation control scheme.