COLREG compliant trajectory planning for autonomous vessels in areas with static and dynamic obstacles

The development of autonomous vessels is a topic of great interest in the maritime industry. Generating trajectories for vessels over long time horizons while respecting multiple sets of rules, is a complicated task. In this contribution, a procedure to generate trajectories that comply with the rules of preventing collisions at sea (COLREGs) is presented. The approach is based on the combination of three methods, namely the rapidly exploring random tree (RRT) algorithm, velocity obstacles (VOs), and motion primitives (MPs). In this approach, the dynamic situation is analyzed and the corresponding COLREG rule is enforced by selecting only valid, i.e., COLREG conform, MPs from a database. This database is created by solving a boundary value problem (BVP) for a set of initial and final conditions. The approach is capable of respecting static and dynamic obstacles and can be used for a variety of vessel classes and time horizons.