Towards optimized instrument panels

Today, automobiles are becoming more and more technologically complex, with more and more built-in driver information systems. This increases the amount and range of information the driver needs to be aware of while driving. For a safe traffic environment, drivers must have their eyes on the road and hands on the wheel rather than on in-vehicle displays and controls. However, many of these in-vehicle systems are safety systems designed to prevent accidents why there is a constant trade-off between monitoring interior systems and exterior road view for possible upcoming hazards. Therefore, in-vehicle information displays must be designed to be conspicuous enough to be noticed and discrete enough not to distract the driver. In this thesis a user-centred approach is used with the aim to optimize driver information presentation by testing display design guidelines, evaluation methods, and display configurations in order to increase the drivers' performance regarding noticing, reading, and understanding in-vehicle information displays while driving safely. In Paper I a literature review of design guidelines regarding optimal presentation in in-vehicle information displays was undertaken. The reviewed guidelines appeared to be coherent and valid for today's automobiles and can, hence, lay the foundation for the design of an optimized display. In Paper II an experimental driving simulator study where 19 participants evaluated two display configuration designs regarding their effect on distraction, noticeability, driver stress, and driving performance during driving while an easy secondary detection task was conducted. The reviewed guidelines from Paper I ensured that results were only effected by the differences between the display configurations. One of the compared display configurations resemble a layout found in automobiles of today, and the other a layout, which according to the literature would improve noticeability, but perhaps be somewhat more distracting. The results showed that the latter display configuration improved driving performance without causing any unnecessary distraction. Papers I and II were mainly focusing on performance based usability, but since image and impression are also part of usability, the aim of Paper III was to study eyetracking based methods' appropriateness for evaluating vehicle information clusters, and to connect perceptions of vehicle information clusters with quantifiable measures. Twenty-three subjects participated in the study where a triangulation of eye-tracking, semantic environmental description, and interviews was made. The results indicated that gaze behaviour data adds no additional value compared to if the other assessment methods were used on their own. All together, this thesis brings up important aspects that have implications for the design of in-vehicle information and systems, and gives guidance on how to optimize instrument panels to achieve a safer traffic environment.OPTIVe - Optimised system integration for safe interaction in vehicle