Adding Formal Specifications to Requirements Patterns∗

Embedded systems usually must achieve a higher level of robustness and reliability because they control real-world physical processes or devices upon which we depend, frequently, in a critical way. Consequently, methods for modeling and developing embedded systems and rigorously verifying behavior before committing to code are increasingly important. In order to use object-oriented development techniques and UML for embedded systems, we previously developed a framework for adding formal semantics to a collection of UML diagrams that enable the automated derivation of formal language specifications for those diagrams. Recently, we also identified a number of requirements patterns for use in the development of requirements and high-level design for embedded systems, and constructed a requirements pattern template. This paper describes how we have augmented the template to include requirements constraints that might be applicable when using a given pattern. With the ability to generate formal specifications from the UML diagrams, these constraints can be analyzed using existing model checkers. We also include a description of how the requirements patterns have been used to model and formally analyze an automotive embedded system.