Accessing and Selecting Menu Items by In-Air Touch

Is it possible to realize a non-visual, purely tactile version of an icon-based menu? Driven by such question, a hierarchical tactile dock was designed for an array of ultrasound emitters. The icons were conceived as spatio-temporal variable-speed sequences of tactile stimulation points, that are passively perceived as trajectories drawn on the palm of the hand. The recognition rate on four icons largely improved prior performance results obtained by active haptic exploration. As a result, a four-icons set can be used as the first level of a hierarchy of symbols that can be navigated by touch and gesture. The design process, based on controlled recognition experiments and exploration of dissimilarity data, can be iterated to converge to a set of icons that are suitable for a functional tactile dock