Maintaining consistency between system architecture and dynamic system models with SysML4Modelica

Abstract

Nowadays many technical products include mechatronic systems that incorporate components from multiple disciplines --- mechanical, electronic, controls and software. In model-based design of mechatronic systems different kinds of models are used to model various system aspects, such as the system structure or its dynamic behavior. This often leads to a process that involves multiple formalisms and is concerned with the coupling of and transformation between models described in these formalisms. In this paper, an approach based on the OMG SysML-Modelica specification is introduced to facilitate the formal definition of dependencies between a system architecture view described in SysML and a continuous system dynamics view defined in Modelica. We discuss the problem of maintaining consistency between these two views. Taking into account the characteristics of the modeling languages, the design workflows, and current modeling tool capabilities, we present the advantages and challenges of modeling the dynamic behavior completely in SysML4Modelica followed by a transformation to Modelica. To overcome the disadvantages, a "mixed-paradigm" approach is proposed in which different parts of the dynamic system behavior are modeled at different levels of abstraction with different formalisms. Finally, an illustrative example is provided which focuses on practical issues related to the usage of SysML4-Modelica.