Formal description of multi-touch interactions

The widespread use of multi-touch devices and the large amount of research that has been carried out around them has made this technology mature in a very short amount of time. This makes it possible to consider multi-touch interactions in the context of safety critical systems. Indeed, beyond this technical aspect, multi-touch interactions present significant benefits such as input-output integration, reduction of physical space, sophisticated multi-modal interaction? However, interactive cockpits belonging to the class of safety critical systems, development processes and methods used in the mass market industry are not suitable as they usually focus on usability and user experience factors upstaging dependability. This paper presents a tool-supported model-based approach suitable for the development of interactive systems featuring multi-touch interactions techniques. We demonstrate the possibility to describe touch interaction techniques in a complete and unambiguous way and that the formal description technique is amenable to verification. The capabilities of the notation is demonstrated over two different interaction techniques (namely Pitch and Tap and Hold) together with a software architecture explaining how these interaction techniques can be embedded in an interactive application.