Specification of Cyber-Physical Components with Formal Semantics - Integration and Composition

Model-Based Engineering of Cyber-Physical Systems (CPS) needs correct-by-construction design methodologies, hence CPS modeling languages require mathematically rigorous, unambiguous, and sound specifications of their semantics. The main challenge is the formalization of the heterogeneous composition and interactions of CPS systems. Creating modeling languages that support both the acausal and causal modeling approaches, and which has well-defined and sound behavior across the heterogeneous time domains is a challenging task. In this paper, we discuss the difficulties and as an example develop the formal semantics of a CPS-specific modeling language called CyPhyML. We formalize the structural semantics of CyPhyML by means of constraint rules and its behavioral semantics by defining a semantic mapping to a language for differential algebraic equations. The specification language is based on an executable subset of first-order logic, which facilitates model conformance checking, model checking and model synthesis.