Design of body-grounded tactile actuators for playback of human physical contact

We present four wearable tactile actuators capable of recreating physical sensations commonly experienced in human interactions, including tapping on, dragging across, squeezing, and twisting an individual's wrist. In seeking to create tactile signals that feel natural and are easy to understand, we developed movement control interfaces to play back each of these forms of actual human physical contact. Through iterative design, prototyping, programming, and testing, each of these servo-motor-based mechanisms produces a signal that is gradable in magnitude, can be played in a variety of temporal patterns, is localizable to a small area of skin, and, for three of the four actuators, has an associated direction. Additionally, we have tried to design toward many of the characteristics that have made high frequency vibration the most common form of wearable tactile feedback, including low cost, light weight, comfort, and small size. Bolstered by largely positive comments from naive users during an informal testing session, we plan to continue improving these devices for future use in tactile motion guidance.