ASV Finite-time-formation Control Based on an Improved Extended State Observer and Saturation Functions

This paper explores the finite-time formation control of an autonomous surface vessel (ASV) under the conditions of external and internal disturbances, as well as input saturation-constrained conditions. An extended state observer (ESO) is improved to uniformly view the internal and external disturbances to which the system is subjected as composite disturbances, which is estimated and fed back into the control system. A new saturation function in the form of a single saturation function is designed to consider the saturation constrained problem. A formation control algorithm is designed based on an improved ESO and saturation functions. The Lyapunov method combined with LaSalle invariant set theory is used to provide a global finite-time consistency proof of the system. Finally, the effectiveness, anti-saturation, and fast convergence of the controller are demonstrated by simulation comparisons.