Are 5 buttons enough

Abstract

Although alternative means of text input in vehicles have already been developed, touchscreen keyboards still pose a standard solution for this input in modern vehicles. Until alternative means of text input will be widely available in vehicles, it is important to further investigate potential improvements in button text input on touch screens. This paper presents a study in which we compared three means of text input for navigation destination entry on a touchscreen in the central console: two keyboards using a QWERTY and an ABC layout, respectively, and a novel 5Button input approach using only 5 buttons to type in city names. The study focused on performance, distraction, and user experience caused by the different keyboards. Results show that the QWERTY and ABC keyboards performed better in terms of perceived workload than the 5Button approach. Performance and perceived usability were best with the QWERTY keyboard, even compared to the ABC keyboard. No significant differences between the systems were found in lane keeping behavior. The main downside of the 5Button approach was the increase of mental workload compared to the other keyboards.