In-vehicle technologies (IVT), such as telematics, entertainment devices, and cell phones, create additional tasks for the driver, possibly also creating safety concerns. This article reports on a study undertaken to examine the effects of display clutter from overlay, display separation, and modality on driving and IVT task performance. Using a fixed-base simulator, the study had 22 drivers driving different routes and responding to infrequent, unexpected road hazards while engaging in a phone number task. The study used visual displays (on a head-up) or head-down display (HDD), or digits were presented auditorily. The results showed no general differences in performance for the adjacent and overlay displays; however, there were costs associated with the HDD and auditory display for some measures (in particular, responses to hazard events were slowed when drivers used the HDD). The authors conclude with a brief discussion of the implications of this research for the placing of displays in the vehicle.
Abstract