Haptic phonemes: basic building blocks of haptic communication

A haptic phoneme represents the smallest unit of a constructed haptic signal to which a meaning can be assigned. These haptic phonemes can be combined serially or in parallel to form haptic words, or haptic icons, which can hold more elaborate meanings for their users. Here, we use phonemes which consist of brief (<2 seconds) haptic stimuli composed of a simple waveform at a constant frequency and amplitude. Building on previous results showing that a set of 12 such haptic stimuli can be perceptually distinguished, here we test learnability and recall of associations for arbitrarily chosen stimulus-meaning pairs. We found that users could consistently recall an arbitrary association between a haptic stimulus and its assigned arbitrary meaning in a 9-phoneme set, during a 45 minute test period following a reinforced learning stage.