A Discussion about Human-Computer Interaction Requirements for Ubiquitous Systems

The ubiquitous computing paradigm was coined by Mark Weiser almost twenty years ago and we still don't have any sound method to design a good ubiquitous system. Part of this problem rests on Human-Computer Interaction requirements to be used on a traditional software development process, like UML, for example. Ubiquity usually means effortless and intuitive Human-Computer interfaces with high degree of interactivity. In this context, is very difficult to define and describe user interaction requirements using traditional tools like Use Cases. In our work we discuss the main requirements for ubiquitous systems, in particular, Human-Computer Interaction requirements, highlighting the differences with non-ubiquitous systems. We also discuss methods to adapt Use Cases to better represent dynamic and flexible nature of ubiquitous user iterations, as a starting point for software development process of ubiquitous systems.