Supporting the Development Process of Multimodal and Natural Automotive User Interfaces

Nowadays, driving a car places multi-faceted demands on the driver that go beyond maneuvering a vehicle through road traffic. The number of additional functions for entertainment, infotainment and comfort increased rapidly in the last years. Each new function in the car is designed to make driving as pleasant as possible but also increases the risk that the driver will be distracted from the primary driving task. One of the most important goals for designers of new and innovative automotive user interfaces is therefore to keep driver distraction to a minimum while providing an appropriate support to the driver. This goal can be achieved by providing tools and methods that support a human-centred development process. In this dissertation, a design space will be presented that helps to analyze the use of context, to generate new ideas for automotive user interfaces and to document them. Furthermore, new opportunities for rapid prototyping will be introduced. To be able to evaluate new automotive user interfaces and interaction concepts regarding their effect on driving performance, a driving simulation software was developed within the scope of this dissertation. In addition, research results in the field of multimodal, implicit and eye-based interaction in the car are presented. The different case studies mentioned illustrate the systematic and comprehensive research on the opportunities of these kinds of interaction, as well as their effects on driving performance. We developed a prototype of a vibration steering wheel that communicates navigation instructions. Another prototype of a steering wheel has a display integrated in the middle and enables handwriting input. A further case study explores a visual placeholder concept to assist drivers when using in-car displays while driving. When a driver looks at a display and then at the street, the last gaze position on the display is highlighted to assist the driver when he switches his attention back to the display. This speeds up the process of resuming an interrupted task. In another case study, we compared gaze-based interaction with touch and speech input. In the last case study, a driver-passenger video link system is introduced that enables the driver to have eye contact with the passenger without turning his head. On the whole, this dissertation shows that by using a new human-centred development process, modern interaction concepts can be developed in a meaningful way.