A Failure Model Library for Simulation-based Validation of Functional Safety

abstract

Simulation-based Fault Injection (FI) is highly recommended by functional safety standards in the automotive and aerospace domains, in order to “support the argumentation of completeness and correctness of a system architectural design with respect to faults” (ISO 26262). We argue that a library of failure models facilitates this process. Such a library, firstly, supports completeness claims through, e.g., an extensive and sys tematic collection process. Secondly, we argue why failure model specifcations should be executable—to be implemented as FI operators within a simulation framework—and parametrizable—to be relevant and accurate for different systems. Given the distributed nature of automotive and aerospace development processes, we moreover argue that a data-flow-based definition allows failure models to be applied to black-box components. Yet, existing sources for failure models provide fragmented, ambiguous, incomplete, and redundant information, often meeting neither of the above requirements. We therefore introduce a library of 18 executable and parameterizable failure models collected with a systematic literature survey focusing on automotive and aerospace Cyber-Physical Systems (CPS). To demonstrate the applicability to simulation-based FI, we implement and apply a selection of failure models to a real-world automotive CPS within a state-of-the-art simulation environment, and highlight their impact.