A model-based and simulation-assisted FMEDA approach for safety-relevant E/E systems

Certifying an electrical/electronic system as functionally safe requires a range of analysis and assessment procedures, which must be performed during the different design and manufacturing phases. In the automotive context, the ISO 26262 standard prescribes a set of methods, including FMEDA (Failure Modes, Effects, and Diagnostic Analysis), to evaluate the safety integrity level of the product. FMEDA is a well-established technique in the industry, however, it still demands cumbersome and error-prone manual tasks. In this paper, we present a model-based approach which enhances the FMEDA process for complex safety-related systems and subsequently achieves effort savings reaching 60% in comparison to the manual procedure. This is realized by formalizing the FMEDA structure and applying a database of failure modes derived from safety standards, recognized fault catalogues, and recent project perceptions. The simulation aspect of the approach enables the systematic composition and the automated assembly of component FMEDAs. It provides a new verification capability for FMEDAs in the sense that potential deficiencies or inconsistencies made by safety analysts can be detected and appropriately corrected.