Bounded controllers for LOS-based coordinated path following in networks of marine surface vehicles with delayed communications

The purpose of this paper is to develop a new type of coordinated path following controllers for multiple marine surface vehicles (MSVs) which track parameterized paths under the influence of time-varying communication delays. For the kinematic level, Line-of-Sight (LOS)-based coordinated guidance laws are derived to generate the desired velocities and heading angles which need to be tracked in the nonlinear dynamic control. For the kinetic level, bounded control inputs are designed to guarantee that each MSV meets the desired cooperative tracking behavior through the feedback control by tracking the reference signals. The main advantages that differ from the current coordinated path following designs are that: First, for on-board control layer, coordination controllers are derived over a delayed communication network on transmitting path variables without the assumption that individual path following errors are 0; second, time-varying delayed distributed speed estimators are designed to handle the communication delays from task layer; third, bounded control scheme for LOS-based coordinated path following is proposed to avoid input saturations by incorporating one-step ahead backstepping method. The global asymptotic stabilities are obtained. Simulation results are provided to validate the effectiveness of the method.