USV Geometric Collision Avoidance Algorithm for Multiple Marine Vehicles

In recent years, Unmanned Surface Vehicles (USVs) have grown in popularity, with an increasing number of applications in the civil, military and research domains. When the USVs are operating in the same area with other marine vessels, the collision avoidance algorithm is the key to keep the safety of both the ownship vehicle and the encountered vessels. This paper presents the development and validation of the geometric collision avoidance algorithm based on the International Regulations for Preventing Collisions at Sea (Colregs). The proposed algorithm allows the USV to avoid multiple dynamic and static vessels simultaneously while obeying the Colregs and keeping the USV a constant clearance from the collision risk. The proposed algorithm includes collision detection algorithm, decision making, collision resolution algorithm and resolution guidance algorithm. The collision detection algorithm describes the process of identifying the intruders as a collision. The decision making algorithm will take into account of Colregs and the traffic information to make the decision between keep-way and give-way. If there is a collision risk and the USV should give-way, the collision resolution waypoint will be generated by the collision resolution algorithm. Then the resolution guidance algorithm will be implemented to ensure the safety of the USV while the USV is avoiding the intruders. Finally, the proposed algorithm was validated in both multiple dynamic intruders scenario and the multiple static-dynamic mixed intruders scenario.