Designing and Evaluating a Vibrotactile Language for Sensory Substitution Systems

The sense of touch can be used for sensory substitution, i.e., to represent visual or auditory cues to impaired users. Sensory substitution often requires the extensive training of subjects, leading to exhaustion and frustration over time. The goal of this paper is to investigate the ability of the subjects to recognize alphanumeric letters on 3 × 3 vibration array, where the subjects can fully personalize the variables including spatial location, vibratory rhythm, burst duration and intensity. We present a vibrotactile device for delivering the spatiotemporal letter patterns while maintaining the high level of expressiveness. The results prove that this system is an effective solution with a low cognitive load for visually/auditory impaired people and for any context that would benefit from leaving the eyes/ears free for other tasks.