T9+HUD: Physical Keypad and HUD can Improve Driving Performance while Typing and Driving

We introduce T9+HUD, a text entry method designed to decrease visual distraction while driving and typing. T9+HUD combines a physical 3x4 keypad on the steering wheel with a head-up-display (HUD) for projecting output on the windshield. Previous work suggests this may be a visually less demanding way to type while driving than the popular case which requires shifts of visual attention away from the road. We present a prototype design and report first results from a controlled evaluation in a driving simulator. While driving, the T9+HUD text entry rate was equal compared to a dashboard-mounted touchscreen device, but it reduced lane deviations by 70%. Furthermore, there was no significant difference between T9+HUD and baseline driving in lane-keeping performance. T9+HUD decreased glance time off road by 64% in comparison to the touchscreen QWERTY. We conclude that the data are favorable and warrant more research on attention-reducing text input methods for driving.