Transformation of Failure Propagation Models into Fault Trees for Safety Evaluation Purposes

In this paper, we apply model-driven techniques to create a link between bottom-up and top-down safety analysis methods. Around MetaFPA, an internal framework for Metamodeling-based Failure Propagation Analysis, we build a safety evaluation environment integrating standard tools used for FMEDA: Failure Modes, Effects, and Diagnostic Analysis (e.g., Excel spreadsheets) and FTA: Fault Tree Analysis (e.g., Isograph's Reliability Workbench (TM)). The environment contains data exchange and conversion utilities and implements an algorithm to synthesize fault trees out of failure propagation models created with MetaFPA. A case study of an Electric Power Steering (EPS) system shows an effort reduction of up to 70% in creating and handling data-intensive failure analysis models compared to manual approaches. Furthermore, the productive deployment of the environment simplifies safety engineering tasks and helps to advance the quality of safety-relevant components and systems.