Enhancing interactions for in-car voice user interface with gestural input on the steering wheel

Abstract

Voice user interfaces (VUI) are becoming indispensable in car for offering drivers the opportunity to make distraction-free inputs and conduct complex tasks. However, the usability and control efficiency of today's VUI remain to be enhanced due to its sequential nature. In this work, we explored gestural input on the steering wheel to improve the interaction efficiency of VUI. Based on limitations in VUI, we designed novel gestural commands on the steering wheel to augment them. We also elicited corresponding user-defined gestures by exploring drivers' touch behavior. Then, we implemented a prototype attached to the steering wheel for recognizing gestures. Finally, we evaluated our system's usability regarding driving performance, interaction efficiency, cognitive workload and user feedback. Results revealed that our system improved the control efficiency of VUI and reduced workload without a significant reduction in driving distraction than just using VUI.