Coordinated Swarm Operations of Unmanned Surface Vehicles for Coastal Surveillance and Search and Rescue Missions

Over the past decades, the use of marine autonomous systems has grown exponentially, thanks to their simplicity, versatility, and significant technological advancements. Unmanned Surface Vehicles (USVs) have emerged as indispensable tools for critical maritime applications, such as coastal surveillance, search and rescue (SAR) operations, and environmental monitoring, where speed, endurance, and precision are essential. These applications often involve challenges that are either too hazardous or too demanding for human operators, such as operating in adverse weather conditions or covering vast, inaccessible areas. Recent research has increasingly focused on cooperative formations or swarms of USVs and UAVs (Unmanned Aerial Vehicles). These formations not only enable the execution of complex missions more effectively than a single vehicle but also reduce the costs and individual payload requirements of each unit. Additionally, such formations improve the robustness and reliability of the system: in case of failure of one USV, the swarm can dynamically reconfigure itself, ensuring mission continuity and adaptability in real-time. Despite their potential, the effective coordination of USVs and UAVs in such swarms presents significant challenges. These include ensuring autonomous operation in dynamic environments, optimizing energy consumption given limited fuel or battery capacity, and enabling adaptive task allocation while maintaining real-time communication in potentially low-bandwidth conditions. Addressing these challenges is crucial, especially in time-critical SAR scenarios where rapid response and coverage are vital. This paper introduces a novel swarm coordination algorithm tailored to USV and UAV formations, based on an adaptation of the Vehicle Routing Problem (VRP). The algorithm optimizes the trajectories of multiple USVs while ensuring seamless collaboration with a mothership, which serves as a central hub for refueling, communication, and coordination. Numerical simulations developed in Matlab/Simulink are presented to validate the effectiveness of the algorithm across various coastal surveillance and SAR scenarios. The results demonstrate the potential of the approach to improve mission success rates and operational robustness in complex maritime environments.