Modelling of Submarine Navigation by Nonmonotonic Logic

Simulations of naval action estimate the operational performance of warships or submarines for a given scenario. In common models, the operator's reactions are predefined. This is not realistic: the operator's decision can produce unexpected reactions. This paper presents a method to model operator decision in simulations. This method allows to reason about incomplete, revisable and uncertain information: an operator has partial information about his environment only and must revise his decisions. Our method uses a nonmonotonic logic: the rules of behavior are formalized with default logic, to which we added a consideration of time. Our method uses preferences to manage choice between different rules, with simple probabilistic techniques. This method has been implemented in Prolog, interfaced to DCNS simulator framework and applied to a scenario involving two adverse submarines.