Analysis and synthesis of the behaviour of complex programmable electronicsystems in conditions of failure

This paper introduces a new method for safety analysis which modifies, auto mates and integrates a number of classical safety analysis techniques to ad dress some of the problems currently encountered in complex safety assessme nts. The method enables the analysis of a complex programmable electronic s ystem from the functional level through to low levels of its hardware and s oftware implementation. In the course of the assessment, the method integra tes design and safety analysis and harmonises hardware safety analysis with the hazard analysis of software architectures. It also introduces an algor ithm for the synthesis of fault trees, which mechanises and simplifies a la rge and traditionally problematic part of the assessment, the development o f fault trees. In this paper, we present the method and discuss its applica tion on a prototypical distributed brake-by-wire system for cars. We argue that the method can help us rationalise and simplify an inherently creative and difficult task and therefore gain a consistent and meaningful picture of how a complex programmable system behaves in conditions of failure. (C) 2001 Elsevier Science Ltd. All rights reserved.