Integrating SysML with UML, MARTE, UPDM/UAF, and Modelica
Domain 2 examines how SysML models exchange meaning with UML, MARTE, UPDM/UAF, and Modelica. The exam expects deliberate integration choices and preserved traceability when semantics differ.
UML and profile-based languages
SysML is a UML profile, so a UML model can apply SysML and retain UML constructs. Integration is usually a shared repository and profile application, not file conversion. MARTE adds timing, performance, and resource modeling; apply MARTE stereotypes such as «Resource» or «SchedulableResource» to SysML parts, then analyze. UPDM, an OMG enterprise-architecture profile based on DoDAF/MODAF and superseded by UAF, maps SysML blocks to operational and system elements within one repository. Version alignment matters: UPDM 2.x and UAF 1.x are not interchangeable.
Modelica and executable behavior
Modelica is equation-based, acausal, and continuous/discrete; SysML is largely causal and structural/behavioral. Do not expect a lossless automatic mapping. Practical integration uses transformation or co-simulation via FMI: export a Modelica model as a Functional Mock-up Unit and connect it to SysML parameter/port values, or generate Modelica skeletons from SysML structure and keep trace links. Units and connector causality must be reconciled.
Worked example
A SysML block Camera has flow port imageOut and a parametric constraint frameRate. A Modelica model computes thermal drift. Integrate by co-simulation: expose Modelica inputs (power, ambient) and output (drift) through an FMU; map SysML value properties to FMU variables; record a «trace» link from the SysML constraint to the Modelica model. Reasoning: keep architecture in SysML and physics in Modelica; use FMI as the contract; validate units and step size.
Traps
Assuming profile stacking is conflict-free; mixing UPDM and UAF versions; treating Modelica connectors as identical to SysML proxy ports; ignoring acausal versus causal semantics; claiming a standard SysML-to-Modelica mapping exists.