Automatic Code Generation of Safety Mechanisms in Model-Driven Development

In order to meet regulatory standards in the domain of safety-critical systems, these systems have to include a set of safety mechanisms depending on the Safety Integrity Level (SIL). This article proposes an approach for how such safety mechanisms may be generated automatically via Model-Driven Development (MDD), thereby improving developer productivity and decreasing the number of bugs that occur during manual implementation. The approach provides a structured way to define safety requirements, which may be parsed automatically and are used for the generation of software-implemented safety mechanisms, as well as the initial configuration of hardware-implemented safety mechanisms. The approach for software-implemented safety mechanisms relies on the Unified Modeling Language (UML) for representing these mechanisms in the model and uses model transformations to realize them in an intermediate model, from which code may be generated with simple 1:1 mappings. The approach for hardware-implemented safety mechanisms builds upon a template-based code snippet repository and a graphical user interface for configuration. The approach is applied to the development of a safety-critical fire detection application and the runtime of the model transformations is evaluated, indicating a linear scalability of the transformation steps. Furthermore, we evaluate the runtime and memory overhead of the generated code.