A dialogue-based approach to the design of user interfaces for supervisory control systems

Supervisory control systems (SCS), such as those used in process control, are notable for very large information spaces, highly concurrent activity and time-critical operator and system response. The arduous task of monitoring and controlling the physical process is exacerbated by the cognitive burden of comprehending and manipulating the interface itself. Problems arise because the task of managing the interface impedes the task the interface is supposed to serve: managing the control system and physical process. The interface is both the place and the means of human-computer communication: an appropriate model of this communication is central to the design of effective SCS-user interfaces. This paper presents an approach to specifying the role of the human-computer interface as facilitator and mediator of multiple concurrent dialogues. In addition, an information taxonomy based on the operator's task of monitoring and controlling an SCS is defined. The model's relevance to the design of intelligent user interfaces is noted.