Leader-Follower Formation and Tracking Control of Underactuated Surface Vessels

TL;DR

This paper introduces a simple, robust control method for formation and trajectory tracking of underactuated surface vessels with only two propellers, ensuring global stability and disturbance robustness.

Contribution

It presents a novel cascaded control design combining kinematic and kinetic controllers for underactuated vessels, applicable to multi-vehicle formations with proven stability.

Findings

Guarantees uniform global asymptotic stability

Ensures robustness to bounded disturbances

Applicable to multi-vehicle formation control

Abstract

This Technical Note presents a simple control approach for global trajectory tracking and formation control of underactuated surface vessels equipped with only two propellers. The control approach exploits the inherent cascaded structure of the vehicle dynamics and is divided into control designs at the kinematics and kinetics levels. A controller with a low-gain feature is designed at the kinematics level by incorporating the cascaded system method, persistency of excitation, and the small-gain theorem. Furthermore, a PD+ controller is designed to achieve the velocity tracking at the kinetics level. The proposed control laws are partially linear and saturated linear and easy to implement. Based on a leader-follower scheme, our control approach applies to the formation tracking control problem of multi-vehicle systems under a directed spanning tree topology. Our main results guarantee uniform global asymptotic stability for the closed-loop system, which implies robustness with respect to bounded disturbances in the sense of Malkin's total stability, also known as local input-to-state stability.