On STPA for Distributed Development of Safe Autonomous Driving: An
  Interview Study
Ali Nouri Christian Berger Fredrik Törner
Safety analysis is used to identify hazards and build knowledge during the
design phase of safety-relevant functions. This is especially true for complex
AI-enabled and software intensive systems such as Autonomous Drive (AD).
System-Theoretic Process Analysis (STPA) is a novel method applied in
safety-related fields like defense and aerospace, which is also becoming
popular in the automotive industry. However, STPA assumes prerequisites that
are not fully valid in the automotive system engineering with distributed
system development and multi-abstraction design levels. This would inhibit
software developers from using STPA to analyze their software as part of a
bigger system, resulting in a lack of traceability. This can be seen as a
maintainability challenge in continuous development and deployment (DevOps). In
this paper, STPA's different guidelines for the automotive industry, e.g.
J31887/ISO21448/STPA handbook, are firstly compared to assess their
applicability to the distributed development of complex AI-enabled systems like
AD. Further, an approach to overcome the challenges of using STPA in a
multi-level design context is proposed. By conducting an interview study with
automotive industry experts for the development of AD, the challenges are
validated and the effectiveness of the proposed approach is evaluated.