Component Failure Behaviour: Patterns and Reuse in Automated System Safety Analysis

Recent work in the area of safety analysis has shown that system Fault Trees and Failure Modes and Effects Analyses (FMEAs) can be automatically derived from a topological model of the system that has been annotated with local, component-level, specifications of failure. In this paper, the concept of a component failure specification is extended to enable description and reuse of generalized patterns of failure behaviour that are commonly exhibited by components. A language for the description of such patterns is specified, useful patterns are presented and the use of such patterns is demonstrated on an example of a Time-Triggered system. The paper tentatively concludes that careful reuse of failure patterns in conjunction with automated fault tree and FMEA synthesis algorithms can help to rationalize, and simplify, complex safety assessments.