Event Processing in an Object-Oriented Rule-Based System

Abstract. This paper describes concepts being developed for processing events in a rule-based system, to be deployed in an embedded system that is part of a railway interlocking system, used as a safety-motivated secondary software channel. Events are either status notifications or operator commands, both of which operate on elements in a railway interlocking plant. It is shown that an object-oriented hierarchy of fact types results in a compact set of rules for processing both event types, illustrated by a prototype implementation. Key words: railway interlocking, event processing, production rule system, object-orientedness