A Pattern-Based Approach towards the Guided Reuse of Safety Mechanisms in the Automotive Domain

Abstract

The reuse of architectural measures or safety mechanisms is widely-spread in practice, especially in well-understood domains, as is reusing the corresponding safety-case to document the fulfillment of the target safety goal(s). This seems to harmonize well with the fact that safety standards recommend (if not dictate) performing many analyses during the concept phase of development as well as the early adoption of multiple measures at the architectural design level. Yet this front-loading is hindered by the fact that safety argumentation is not well-integrated into architectural models in the automotive domain and as such does not support comprehensible and reproducible argumentation nor any evidence for argument correctness. The reuse is neither systematic nor adequate.

Using a simplified description of safety mechanisms, we defined a pattern library capturing known solution algorithms and architectural measures/constraints in a seamless holistic model-based approach with corresponding tool support. Based on a meta-model encompassing both development artifacts and safety case elements, the pattern library encapsulates all the information necessary for reuse, which can then be integrated into existing development environments. This paper explores the model and the approach using an illustrative implementation example, along with the supporting workflow for the usage of the approach in both “designer” and “user” roles.