Formal specification of COLREG steering and sailing rules

Kurzfassung

In the context of Maritime Autonomous Surface Ships (MASS), rules on vessel navigation as given by the International Regulations for Preventing Collisions at Sea (COLREGs) evolve from instructions to experienced personnel to technical requirements for automated systems.

In their original form, COLREG steering and sailing rules are informal and open to expert interpretation. There is a lack of clear formal requirements important for the design and validation of automated maritime systems.

In this paper we aim to address this issue by presenting a formal specification of relevant COLREG steering and sailing rules in terms of requirements on the navigation of a power-driven vessel on the open sea. We further discuss how this formalisation may support design, verification, validation and online monitoring of MASS.