A Model-based Approach for the Engineering of Interactive Systems

Designing an interactive system that is usable, reliable, safe and error-tolerant is a difficult, if not impossible, goal, as all these characteristics cannot be guaranteed due to the unpredictability of the humans involved. With the aim of increasing the dependability of critical interactive systems, previous research in the field has focused on completely eliminating error by identifying its source. It is now widely accepted that human "errors" are unavoidable due to the idiosyncratic nature of humans, necessitating an attempt to manage these errors rather than eliminate them. The perspective of blame has also evolved from the isolation of an operator to a broader view of the organization as a whole. However, the broader the perspective, the more information needs to be gathered, and therefore the more complex the organization of this data and the reasoning attached to it.

Beyond this central aspect of human error (works such as report that 80% to 90% of accidents in industry are attributed to human error), other aspects contribute and must therefore be addressed accordingly. Among these, the most important are system usability, reliability and operator training.

The design and implementation of such systems requires the definition of specific methods capable of managing usability, reliability and safety. For many years, human-computer interaction engineering research has been proposing such methods for systems involving simple interaction techniques. The best-known method of designing for usability is called User Centered Design (UCD), and promotes the systematic involvement of users in both the design and evaluation phases. As an extension of these UCD approaches, and in order to cope with these complex combinations of factors and systems, some approaches encourage the use of formal and model-based design methods as a means of representing these components and their interrelationships, whether during design, construction or analysis.

This article presents the principles of an integrated, generic and multidisciplinary modeling framework for the design of interactive systems, including mission-critical systems. The aim is to propose means such as model-based design techniques, notations, tools and methods, which enable those involved in the process to take into account and manage erroneous human and/or system behavior. The idea of this approach is not new, as modeling processes and techniques have been defined and widely applied in the field of critical systems (model-based development (MBD)...