Anticipating Accidents through Reasoned Simulation

A key goal of the System-Theoretic Process Analysis (STPA) hazard analysis technique is the identification of loss scenarios - causal factors that could potentially lead to an accident. We propose an approach that aims to assist engineers in identifying potential loss scenarios that are associated with flawed assumptions about a system's intended operational environment. Our approach combines aspects of STPA with formal modelling and simulation. Currently, we are at a proof-of-concept stage and illustrate the approach using a case study based upon a simple car door locking system. In terms of the formal modelling, we use Extended Logic Programming (ELP) and on the simulation side, we use the CARLA simulator for autonomous driving. We make use of the problem frames approach to requirements engineering to bridge between the informal aspects of STPA and our formal modelling.