Structuring Simulink models for verification and reuse

Model-based development (MBD) tool suites such as Simulink and Stateflow offer powerful tools for design, development, and analysis of models. These models can be used for several purposes: for code generation, for prototyping, as descriptions of an environment (plant) that will be controlled by software, as oracles for a testing process, and many other aspects of software development. In addition, a goal of model-based development is to develop reusable models that can be easily managed in a version-controlled continuous integration process. Although significant guidance exists for proper structuring of source code for these purposes, considerably less guidance exists for MBD approaches. In this paper, we discuss structuring issues in constructing models to support use (and reuse) of models for design and verification in critical software development projects. We illustrate our approach using a generic patient-controlled analgesia infusion pump (GPCA), a medical cyber-physical system.