Hydrographic Objects’ Domains in Ship Route Planning in Restricted Areas

The basic requirement for ship voyage planning is to determine a safe route while meeting certain safety and economic criteria. ECDIS are a commonly used tool for this purpose. Route planning is normally accomplished by setting route cross track limit-XTE. The XTE value can be adjusted on individual sections of the planned route. As a complementary criterion, the own ship domain is proposed, understood as the area around the ship which is to remain free of other objects. The concept of a hydrographic object domain, analogous to the vessel domain, is proposed. The proposed domain complements existing safety criteria, particularly the criterion of a safe passing distance, and can also be used to define the safe cross-track error (XTE) limit. Different types of these objects are considered, and their classification is proposed. A methodology for determining such domains is presented, consisting of a vessel track analysis method (based on AIS data) and specific methods for determining domains for different types of hydrographic objects. Based on actual recorded Automatic Identification System (AIS) data for conventional ships, domains of fixed objects and navigational hazards have been determined. The domains of hydrographic objects may be applied to the delineation of ‘NoGo areas’ around them in nautical charts.