Learning Vibes: Communication Bandwidth of a Single Wrist-Worn Vibrotactile Actuator

Vibrotactile feedback is increasingly common in wearable wristband devices. While much work has explored specific mappings in navigation and guidance tasks and to close the action-confirmation loop during interactions, little has focused on evaluating the communication capacity of the wrist and how it improves everyday interactions and tasks. To study these questions, we used information transfer as a metric to explore the space of signal variations within a single vibrotactile actuator (e.g., frequency, amplitude, and modulation). We ran a user study with the salient haptics cues to determine how well people were able to identify them without training on the dorsal side of the wrist, if they could interpret them better with training, and if that knowledge could be transferred to a secondary, untrained location (volar side of the wrist). Our results suggest that people are able to interpret at least 5 of the 8 cue variations, and are better able to recognize vibrotactile signals with training. We discuss the implications of the results for enabling vibrotactile interactions on the wrist.