Application of hardware reliability calculation procedures according to ISO 26262 standard

Abstract

The second edition of standard ISO 26262 (ed. 2018) for functional safety assessment in the automotive industry requires a hardware evaluation using the probabilistic metric for random hardware failures (P-MHF). The standard for mentioned purpose highly recommends the fault tree analysis (FTA) utilization but does not give any specific calculation example. Therefore, this article describes computational procedures with derivation and explanation of mathematical formulas for various hardware architectures of electronic systems. Described formulas consider impact of multiple failures and impact of elf-tests, but formulas are relatively simple. This simplicity allows them to be used in the early stages of hardware development when frequent hardware design changes can be expected. Thus, the article with attached case study is intended not only for scientists but also for developers of critical safety-related electronic systems in the automotive industry.