Model-based hazard and impact analysis

Hazard and impact analysis is an indispensable task during the specification and development of safety-critical technical systems, and particularly of their software-intensive control parts. There is a lack of methods supporting an effective (reusable, automated) and integrated (cross-disciplinary) way to carry out such analyses. This report was motivated by an industrial project whose goal was to survey and propose methods and models for documentation and analysis of a system and its environment to support hazard and impact analysis as an important task of safety engineering and system development. We present and investigate three perspectives of how to properly (i) encode safety-relevant domain knowledge for better reuse and automation, (ii) identify and assess all relevant hazards, as well as (iii) pre-process this information and make it easily accessible for reuse in other safety and systems engineering activities and, moreover, in similar engineering projects. The first perspective focuses on the transition from informal to a formal, model-based representation of knowledge about hazards and system requirements. The second perspective provides a methodology to identify and treat hazards based on a state-machine model of the considered system. The third perspective shows a tool-supported procedure for modeling faulty behaviors of both, physical and software components in a qualitative way and for automatically determining their impact based on the structural description of the physical and computational/software parts of the system and a model of the environment. All perspectives are shown in their characteristics and capabilities by means of a case study on a drive train in the commercial road vehicle domain.