Communication-Efficient Distributed Local Formation Cost Optimizations for the Internet of Marine Surface Vehicles Under Random Networks

Formation control is a promising technique for the coordinated operation of networked unmanned surface vehicles (NUSVs) to provide mobility services in the marine Internet of Things (M-IoTs). In practical M-IoTs applications, individual vehicles are typically required to satisfy their own local mission objectives while maintaining cooperative formation behavior with the entire fleet. However, most existing formation control approaches fail to explicitly address the individual formation cost of local vehicles in such scenarios. Moreover, limited communication bandwidth, unreliable link connections, and complex model dynamics further complicate this problem for NUSVs. To address these challenges, this paper develops a non-cooperative dynamic formation game (NCDFG) framework to address the formation problem of NUSVs from the perspective of optimizing individual mission costs of vehicles. To solve the formulated problem, a distributed segment Nash Equilibrium (NE) seeker (DSNES) is first designed to generate the optimal formation trajectories for local vehicles under discrete communications and unreliable links. To ensure the network resource utilization efficiencies, the event-driven communication scheme related to the DSNES is subsequently developed. Notably, to guarantee the NE convergence of DSNES under event-driven communications and possible link interruptions, a segment estimation protocol is integrated to obtain accurate internal states of neighbors between successive communications. Building upon the DSNES, the local NE trajectory tracking controller (NETTC) is finally developed to steer underactuated vehicles moving along their corresponding NE trajectories. Finally, theoretical analysis and semi-physical validations are conducted to demonstrate the effectiveness of the proposed approach.