Effect of selected in-vehicle route guidance systems on driver reaction times

Experiments were conducted in a fixed-base, high-fidelity simulator to evaluate selected in-vehicle route guidance systems. Drivers navigated a simulated network using five route guidance systems: paper map, head-down turn-by-turn display, head-down electronic route map, head-up turn-by-turn display, and an audio guidance system. The primary measure of driving performance was the reaction time to a scanning task. Other measures included navigation errors, workload, and perception ratings. Censored regression models were developed to study the effect of route guidance type on reaction times. Results indicated that the drivers responded the fastest while using the audio system and the slowest while using the paper map. The head-up turn-by-turn display was associated with lower reaction times compared with an identically designed head-down turn-by-turn display. The head-down electronic map, despite its complexity, performed better than the head-down turn-by-turn display.