Ontology in MBSE How ontologies fit into MBSE

Ontology in MBSE How ontologies fit into MBSE The benefits and challenges

Outline • What MBSE brings to engineering • What Ontology brings to MBSE • How do ontologies get used in MBSE • Benefits of incorporating ontologies • Challenges • Roadmap

What MBSE brings to engineering The use of digital models that represent a system under design or analysis are the primary engineering authority Model Interpretation

Some OMG Terminology Regarding Models OMG distinguishes the model, the modeling language, and the subject of the model Level 1 Model Expressed in Interpreted In Level 0 Subject Modeling Language

What is an Ontology A collection of concepts and relationships used in modeling a domain Example of Vehicle Ontology 2 -wheeled Drive Standard specialization classification of vehicles Car Truck Standard list of attributes for vehicles Vehicle Weight Geometry Wheel Is. Part. Of Geometry Type

How is an Ontology Used in MBSE A model may use the concepts from multiple ontologies Uses Concepts from Ontology Modeling Language Expressed in

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California Ontologies may be Organized into hierarchies Foundation Ontologies Base, Mission, Project, Quantities-Units-Dimensions-Values, Analysis, Artifact, Architecture Description Fundamental terms use in all projects, disciplines, and applications use Discipline Ontologies use Mechanical, Electrical, Physics, Thermal, Propulsion, Attitude Control, Navigation, … Discipline-specific terms specified and owned by discipline experts Focus is integration and interoperation use Application Ontologies Kinds of items that are modeled in a project; specified and owned by application experts Star Tracker, Sun Sensor, Reaction Wheel, Thruster, . . 2 -axis vs. 3 -axis S/C; Radio vs. optical comm; … Focus is reuse 7

Benefits of incorporating ontologies into MBSE < Standardization of domain terminology < Enable common understanding of the domain (interoperabilty) < Enable reuse of domain knowledge < Make domain assumptions explicit < Separate domain knowledge from the operational knowledge < Analyze domain knowledge 8

Challenges 1. Determining a hierarchy of candidate ontologies for standardization 2. Coalescing ontology hierarchy with scope and uses relations 3. Getting general acceptance and involvement from appropriate standards bodies 4. Standardizing on suitable logical formalization to express semantics 9

INCOSE MBSE Ontology Roadmap MBSE Capability Reduced cycle times System of systems interoperability Design optimization across broad trade space Cross domain effects based analysis January 29, 2011 Institutionalized MBSE across Academia/Industry Establishing Ontology Standards Well Defined within MBSE Maturity Establishing Formal Semantics For Ontologies Incorporating feedback and republishing Engaging standards bodies Publishing candidate ontologies Ad Hoc use of Ontologies Developing candidate hierarchy of Ontologies Refer to activities in the following areas: • Planning & Support • Research • Standards Development • Processes, Practices, & Methods • Tools & Technology Enhancements • Outreach, Training & Education 2011 INCOSE IW 2011 MBSE Workshop 2020 2025

Inference Standards Modeling Language Standards Metadata Standards Data Interchange Format Standards Recovery Exchange Discovery Common Vocabulary Common Meaning INCREASING INTEROPERABILITY A Stack of Semantic Standards for Ontologies Global Resource Identification Standards Increasing use of standards To enable semantic interoperability