PROCEEDINGS of the HUMAN FACTORS AND ERGONOMICS SOCIETY 47th ANNUAL MEETING – 2003 THE EFFECTS OF HEAD-UP DISPLAY CLUTTER AND IN-VEHICLE DISPLAY SEPARATION ON CONCURRENT DRIVING PERFORMANCE

The introduction of new in-vehicle technologies (IVTs) in automobiles may have important implications for driver safety, especially to the extent that these devices interfere with the primary driving task. Two experiments explored the effects of IVTs on vehicle control and hazard awareness: specifically, we were interested in the impact of visual clutter from head-up display (HUD) overlay as well as the impact of dis-play separation. In experiment 1, twenty-five drivers in a wrap-around simulator drove urban and rural routes while performing a phone number read-back task. Visual displays were located either in a HUD overlaid on the horizon, a HUD positioned 7 ° below the horizon, or on a head-down display (HDD) located near the mid-console. Experiment 2 attempted to replicate some of the key findings in Experiment 1 with more challenging driving conditions (i.e., curved roads, varying fog densities). In general, the results sug-gested that drivers protected the vehicle control task, however there were costs in hazard response time and side task performance with the HDD. We suggest that effective hazard detection requires more focal visual resources whereas vehicle control may utilize ambient resources. The practical and theoretical significance of these findings are discussed. The introduction of new in-vehicle technologies into the automobile creates additional tasks that drivers may perfor