A review of electrotactile stimulation for machine-to-human communication

Tactile stimulation, especially electrotactile stimulation, have been a subject of interest in recent literature for machine-to-human communication (M2HC) of electronically gathered information for the purpose of augmenting and improving the human experience. Electrotactile is a direct noninvasive method for peripheral nerve stimulation that provides a pathway for communication with the brain. However, the widespread use of electrotactile as an M2HC pathway is hampered by the availability and ease of use of mainstream, visual and audio, communication methods and technological challenges with electrotactile stimulation that must be resolved, such as skin condition dependency, neural adaptation, and the lack of a framework for producing consistent electrotactile M2HC. As such, this paper (1) reviews the scientific and engineering literature associated with electrotactile stimulation and associated electronics with a goal of converging disciplinary knowledge of this topic, (2) summarizes recent advances and open challenges in electrotactile stimulation, and (3) discusses available techniques and introduces a unifying model for icon-based electrotactile communication. In contrast to prior review papers on the subject, this paper uniquely focuses on defining electrotactile stimulation as a method for robust machine-to-human communication while compiling and discussing relevant engineering, physiology, and neuroscience issues, thus providing a comprehensive understanding of electrotactile M2HC for the IEEE community.