Hazards in advising autonomy: developing requirements for a hazard modelling methodology incorporating system dynamics

This paper describes the continuation of a research project to identify and develop tools for the identification and management of hazards likely to arise with the quality and reliability of automatic advice - such as in an automated system advisory function, especially where supporting a “Sense & Avoid” capability as embodied within an airborne autonomous system. An earlier literature survey has been used to map detail onto a Use Case model representing an outline certifiable system development process; thereby helping to identify an appropriate research direction within the broad range of potential end-user requirements. From this direction, an approach has emerged to evaluate hypothetical deviations from declared intent within a behavioral modeling framework to be styled upon Owen's STAMP-Based Hazard Analysis (STPA). For this approach an outline exemplar describing an air-proximity hazard arising between two air-vehicles has been developed, and the representation of the control structure and system dynamics describing this model are considered. Arising from this model some consideration is then given towards the expression of a more systematic approach in the construction of such models, leading towards new methods to derive safety requirements for implementation within autonomous air systems.