Multi-touch user interface evaluation for 3D object manipulation on mobile devices

Multi-touch user interfaces (MTUIs) can represent a valuable tool for enhancing human-machine interaction. The naturalness and variety of hand gestures offer a more direct and intuitive form of interaction that can be exploited in a large spectrum of applications. Moreover, 3D visualization on mobile devices is a task required by increasing number of scenarios ranging from video games to engineering. In this paper, the impact of MTUls when applied to 3D scene navigation on handheld devices is investigated. Numerical measures as well as subjective results (based on user feedback) are exploited in order to analyze the effectiveness of MTUIs compared with a traditional button-based user interface. The two GUIs are compared in terms of time and number of interactions to complete three reference tests. In particular, a statistical analysis based on paired t-tests shows how the proposed MTUI can, in general, outperform a traditional button GUI; differences between GUIs are strongly reduced when a fine control of objects is required.