A Bisimulation-Based Design of User Interface With Alerts Avoiding Automation Surprises

In a human-machine system, a user operates a machine by getting information about its behavior through a user interface. If the information is not sufficient to estimate the machine's state, the user may experience automation surprises. Moreover, he/she may misunderstand the current safety-relevant situation of the machine. In this paper, such misunderstanding is called safety confusion. We introduce a notion of safety levels to deal with safety confusion. The goal is to build a safety-relevant human-machine system. For that, first, we use a formal model for modeling the human-machine system. Then, we present (bi)simulation-based conditions under which neither safety confusion nor automation surprises occur in the human-machine system. Next, we present a (bi)simulation-based algorithm to build a user interface and a user model avoiding the automation surprises and safety confusion. Finally, we design an alerting system that warns the user when he/she degrades the safety level so that he/she operates a machine safely.