Checking SysML Models for Co-simulation.

Cyber-physical systems (CPSs) are often treated modularly to tackle both complexity and heterogeneity; and their validation may be done modularly by co-simulation: the coupling of the individual subsystem simulations. This modular approach underlies the FMI standard. This paper presents an approach to verify both healthiness and well-formedness of an architectural design, expressed using a profile of SysML, as a prelude to FMI co-simulation. This checks the conformity of component connectors and the absence of algebraic loops, necessary for co-simulation convergence. Verification of these properties involves theorem proving and model-checking using: FRAGMENTA, a formal theory for representing typed visual models, with its mechanisation in the Isabelle/HOL proof assistant, and the CSP process algebra and its FDR3 model-checker. The paper's contributions lie in: a SysML profile for architectural modelling supporting multi-modelling and co-simulation; our approach to check the adequacy of a SysML model for co-simulation using theorem proving and model-checking; our verification and transformation workbench for typed visual models based on FRAGMENTA and Isabelle; an approach to detect algebraic loops using CSP and FDR3; and a comparison of approaches to the detection of algebraic loops.