SOTIF the Human Factor

Abstract

The ISO/PAS 21448 [1] Safety of the Intended Functionality (SOTIF) specification was published in January 2019. The specification gives the reader a good overview of some of the challenges that designers of semi-autonomous and autonomous vehicles will face. One of the key definitions in the specification is reasonably foreseeable misuse, which is very much a consideration for usability or human factors engineering. Annex E of ISO/PAS 21448 introduces over 3 pages some of the basic concepts of usability engineering, however usability engineering is a large and complex subject that requires a greater emphasis in the paper particularly on the types of methods that could ideally be utilized and also the stages in the SOTIF life-cycle where these techniques could be applied. In this paper we look at usability processes and where and how they could be enhanced in the SOTIF specification to help guide design teams and engineers through the vehicle development process. As usability engineering is such a large subject field it is only possible to give a brief overview in this paper. The terms human factors and usability are interchangeable in this paper usability is used throughout.