Supporting Versatility in Tangible User Interfaces Using Collections of Small Actuated Objects. (Interfaces tangibles polyvalentes a base de collections d'objets mobiles de petite taille)
In this dissertation, I present my work aiming at making tangible user interfaces more versatile with a higher degree of physicality, in order to bridge the gap between digital and physical worlds. To this end, I study and design systems which support interaction with digital information while better leveraging human hand capabilities. I start with an examination of the current related work, and highlight the need for further research towards more versatility with a higher degree of physicality. I argue that the specificity of existing systems tends to impair their usability and diffusion and induce a dependence on screens and other projections as media to represent the digital world. Building on lessons learned from previous work, I choose to focus my work on physical systems made of collections of generic and interactive objects. I articulate my research in four steps. Firstly, I present a study that compares tangible and multitouch interfaces to help assess potential benefits of physical objects. At the same time, I investigate the influence of object thickness on how users manipulate objects. Results suggest that conclusions from numerous previous studies need to be tempered, in particular regarding the advantages of physicality in terms of performance. These results however confirm that physicality improves user experience, due to the higher diversity of possible manipulations. As a second step, I present SmartTokens, a system based on small objects capable of detecting and recognizing user manipulations. I illustrate SmartTokens in a notification and personal task management scenario. In a third step, I introduce Swarm User Interfaces as a subclass of tangible user interfaces that are composed of collections of many interactive autonomous robots. To illustrate them, I present Zooids, an open source open hardware platform for developing tabletop Swarm User Interfaces. I demonstrate their potential and versatility through a set of application scenarios. I then describe their implementation, and clarify design considerations for Swarm User Interfaces. As a fourth step, I define composite data physicalizations and implement them using Zooids. I finally draw conclusions from the presented work, and open perspectives and directions for future work.