Synthetic Fault Mode Generation for Resilience Analysis and Failure Mechanism Discovery

Abstract

Traditional risk-based design processes seek to mitigate operational hazards by manually identifying possible faults and corresponding mitigation strategies–a tedious process which critically relies on the designer's limited knowledge. Resilience-based design, on the other hand, seeks to embody generic hazard-mitigating properties in the system to mitigate unknown hazards, often by modelling the system's response to potential randomly-generated hazardous events. This work creates a framework to adapt these scenario generation approaches to the traditional risk-based design process to synthetically generate fault modes, by representing them as a unique combination of internal component fault states which can then be injected and simulated in a model of the system failure dynamics. Based on these simulations, the designer may then better understand the underlying failure mechanisms and mitigate them by-design. The performance of this approach is evaluated in a model of an autonomous rover, where cluster analysis shows that elaborating the faulty state-space in the drive system using this approach uncovers a wider range of possible hazardous trajectories and failure consequences within each trajectory. However, this increase in hazard information gained from exhaustive mode sampling comes at a high computational expense, highlighting the need for advanced, efficient methods to search and sample the faulty state-space.