A Quantitative Safety Assessment Methodology for Safety-Critical Programmable Electronic Systems Using Fault Injection 2009-01-0760

Given the increased use of programmable embedded electronic systems (PEES) in automotive applications and their vital importance, it is not only important for engineers to design PEES in such a way to meet or exceed safety requirements but also quantify how “safe” these systems are. At the University of Virginia's Center for Safety-Critical Systems, we have developed a safety quantification methodology for embedded real time safety-related systems. The goal of the safety quantification methodology is to provide a generic but rigorous and systematic way of characterizing the dependability behavior of embedded systems that is applicable to a broad range of applications from automotive to nuclear. This paper presents a quantitative safety assessment methodology for safety-critical embedded systems using fault injection (FI). This methodology has been developed, refined and applied to a number of commercial safety-grade systems in the railway, nuclear and avionics industries. Additionally, we present several novel techniques that we developed to overcome long-standing challenges associated with fault injection based safety assessment.