Designing and Evaluating Hand-to-Hand Gestures with Dual Commodity Wrist-Worn Devices

Hand gestures provide a natural and easy-to-use way to input commands. However, few works have studied the design space of bimanual hand gestures or attempted to infer gestures that involve devices on both hands. We explore the design space of hand-to-hand gestures, a group of gestures that are performed by touching one hand with the other hand. Hand-to-hand gestures are easy to perform and provide haptic feedback on both hands. Moreover, hand-to-hand gestures generate simultaneous vibration on two hands that can be sensed by dual off-the-shelf wrist-worn devices. In this work, we derive a hand-to-hand gesture vocabulary with subjective ratings from users and select gesture sets for real-life scenarios. We also take advantage of devices on both wrists to demonstrate their gesture-sensing capability. Our results show that the recognition accuracy for fourteen gestures is 94.6% when the user is stationary, and the accuracy for five gestures is 98.4% or 96.3% when the user is walking or running, respectively. This is significantly more accurate than a single device worn on either wrist. Our further evaluation also validates that users can easily remember hand-to-hand gestures and use our technique to invoke commands in real-life contexts.