Toward multimodality: gesture and vibrotactile feedback in natural human computer interaction

In the present work, users’ interaction with advanced systems has been investigated in different application domains and with respect to different interfaces. The methods employed were carefully devised to respond to the peculiarities of the interfaces under examination. We could extract a set of recommendations for developers. The first application domain examined regards the home. In particular, we addressed the design of a gestural interface for controlling a lighting system embedded into a piece of furniture in the kitchen. A sample of end users was observed while interacting with the virtual simulation of the interface. Based on the videoanalysis of users’ spontaneous behaviors, we could derive a set of significant interaction trends The second application domain involved the exploration of an urban environment in mobility. In a comparative study, a haptic-audio interface and an audio-visual interface were employed for guiding users towards landmarks and for providing them with information. We showed that the two systems were equally efficient in supporting the users and they were both well- received by them. In a navigational task we compared two tactile displays each embedded in a different wearable device, i.e., a glove and a vest. Despite the differences in the shape and size, both systems successfully directed users to the target. The strengths and the flaws of the two devices were pointed out and commented by users. In a similar context, two devices supported Augmented Reality technology, i.e., a pair of smartglasses and a smartphone, were compared. The experiment allowed us to identify the circumstances favoring the use of smartglasses or the smartphone. Considered altogether, our findings suggest a set of recommendations for developers of advanced systems. First, we outline the importance of properly involving end users for unveiling intuitive interaction modalities with gestural interfaces. We also highlight the importance of providing the user the chance to choose the interaction mode better fitting the contextual characteristics and to adjust the features of every interaction mode. Finally, we outline the potential of wearable devices to support interactions on the move and the importance of finding a proper balance between the amount of information conveyed to the user and the size of the device