# The Ocean-Going Autonomous Ship--Challenges and Threats
## 1 Introduction
GEBCO-NF Alumniteam (name after General Bathymetric Chart of the Ocean and Nippon Foundation) developed a system consisted of the AUV Hugin, equipped with a high-resolution synthetic aperture echosounder and multibeam echosounder, positioned from the surface by the unmanned surface vessel SEA-KIT [6; 7; 8]. The same vessel a couple of months later completed the first unmanned passage between Tollesbury in Great Britain to Ostend in Belgium and back, being controlled only by the operators located on shore [9; 10]. The USV's route crossed the busiest shipping route in the world. The beginning of coexistence of manned and unmanned vessels, especially autonomous sea-going vessels, in the same areas at sea, provokes many questions and objections. The most important ones, considering the scope of the paper, are the questions of how to guarantee that autonomous vessels will be at least as safe as modern crewed vessels, while operating in the same areas. Undoubtedly, this is a technological challenge, but there is also a challenge for legislation. It will certainly require corrections to many existing documents and rules, already adopted by the marine community and international treaties. New regulations will affect the variety of issues related to transport of goods, shore infrastructure, insurances, etc. However, the fundamental questions are those related to the effective safety and risk management of this kind of vessel. Classifying societies (for example Pureau Veritas, DNV GL, Lloyd's Register, CCS) and IMO (International Maritime Organization) defined their views on the issue of the construction of unmanned/autonomous ships, usually in the form of guidelines [11; 12; 13; 14; 15]. Unfortunately, in terms of the approach to navigation issues, these are usually quite general statements, similar to: 'the data from various ship's sensors should be gathered and evaluated in order to thoroughly determine the location and heading of the ship. Redundant sensors and positioning by multiple sources should ensure a high degree of data accuracy. The current speed and water depth should be monitored as well'. More specific information is contained in [16] however they refer to the possibilities of the engine room autonomy assurance. [PERSON], in turn, is considering primarily the adequacy of legal documents that currently apply to the perspective of ships without crew [17]. [PERSON] et al. in [18] performed an in depth review of literature on autonomous ships with the conclusion that a lot of publications about the design and safety of such kind of vessels exists, although in the majority of them the navigational aspect is understood as the planning of the trajectory and its realization as the steering process of the vessel. The problem of data acquisition to the steering is somewhat overlooked. Finally, the authors of [18] suggest that it is the right time to shift the research focus from the basic control and safety studies to transportation and logistics applications. In this paper, the authors decided to focus on the navigational aspects of unmanned and autonomous vessels. The role of the Officer of the Watch tends towards being augmented or even replaced by the systems related to the autonomous navigation and automated collision avoidance. Those two aspects, with associated threats and possible solutions, will be presented in the next sections. The main motivation of the authors of this paper to analyze this issue was the active participation in the tests of USV 'Maxlimer'--The unmanned vessel of SEA-KIT type, mentioned above, including her passage through the North Sea, crossing the entrance to the English Channel. Observations of the navigational watch conducted on land, undertaken during this passage and earlier tests, led to the conclusions, listed in Section 4.