Ontologies to Support Customer Requirement Formulation in Aerospace Design

The major goal of customer requirement formulation is to achieve a common understanding between the project stakeholders and the engineering requirements. Many times, this process can be ambiguous, incomplete, and time consuming especially when more than one engineering discipline is involved. Therefore, adequate requirement formulation tools can be a major contributor to solving these challenges. The use of ontologies provides a standardized way of describing concepts in a domain of interest and the relationships between these concepts to better understand the domain as a whole. This paper describes the methodology used to create an ontology derived from twenty customer requirements of a mid-size, twin-engine, commercial transport-class aircraft provided by NASA Ames Research Center. One key stipulation that NASA had was that this ontology effectively captures the relationships that exist between the hardware and software level of each customer requirement. The final ontology was created using Protégé OWL, an open source ontology editor, which will be used by NASA in order to improve the customer requirement creation phase of future NASA products. The ontology and requirements were further generalized into a set of common patterns for describing requirements in this domain. These pattern templates provide a tool to ensure that common styles of requirements have been considered, and that these common styles are uniform. This research paper fills a gap in the customer requirement research field by introducing the use of ontologies and common patterns to reduce ambiguity and repetition.