Evaluation of an Eyes-Free Cursorless Numeric Entry System for Wearable Computers

We report on the results of a user study to investigate the utility of passive haptics for eyes-free numeric entry. This work targets cursorless user interfaces designed for use with a watch-sized wrist-worn computer. Our study compared three approaches for selecting one of a set of eight numeric parameters and entering its value, both with and without visual feedback. The three selection methods utilized physical buttons alone, buttons with a touch-sensor utilizing passive haptics, and the touch sensor with passive haptics alone. The results show that passive haptics allowed users to perform parameter selection and number entry tasks, with statistically insignificant differences in accuracy and speed when used with and without visual feedback. Furthermore, there was no statistically significant difference in accuracy and speed between the button-based methods and the purely touch-sensor-based approaches.