A unified human-computer interaction requirements analysis framework for complex socio-technical systems

Complex socio-technical systems (CSTS) play an important part in the operations of a wide range of large-scale, socially important infrastructure, such as power plants and railways systems. Such systems are highly automated but nonetheless still require substantial human operator involvement and oversight. However, the effectiveness of this operator oversight is often compromised by the fact that such systems are built by combining heterogeneous systems and user interfaces, which can lead to operators being asked to oversee systems that represent vital information using a plethora of incommensurable signals, presenting a very considerable threat not just to the usability of such systems but also to their safety. This article presents a Unified Human-Computer Interaction (HCI) Requirements Analysis Framework (UHRAF) and a Safety and Usability Model (SUM) for analyzing the HCI requirements of a safety-related scenario in a railway system. UHRAF and SUM are used to identify requirement issues in HCI arising from the concurrent development of heterogeneous systems and aim to facilitate the development of relevant HCI design guidelines for CSTS.