Experimental validation of camera-based maritime collision avoidance for autonomous urban passenger ferries

Maritime collision avoidance systems rely on accurate state estimates of other objects in the environment from a tracking system. Traditionally, this understanding is generated using one or more active sensors such as radars and lidars. Imaging sensors such as daylight cameras have recently become a popular addition to these sensor suites due to their low cost and high resolution. However, most tracking systems still rely exclusively on active sensors or a fusion of active and passive sensors. In this work, we present a complete collision avoidance system relying solely on camera tracking. The viability of this autonomous navigation system is verified through a real-world, closed-loop collision avoidance experiment with a single target in Trondheim, Norway in December 2022. Accurate tracking was established in all scenarios and the collision avoidance system took appropriate actions to avoid collisions.