A simulator evaluation of five in-vehicle route guidance systems

Experiments were conducted in a fixed base high fidelity simulator to study the effect of in-vehicle route guidance devices on the attentional demands of driving. Drivers navigated a simulated network using five route guidance systems: paper map, heads-down turn-by-turn display, heads-down electronic route map, heads-up turn-by-turn display, and audio guidance system. Dependent variables included reaction times to a roadside scanning task, number of navigation errors and subjective workload. Results indicated the paper map to be associated with the longest reaction time and the highest workload. The audio system was associated with the shortest reaction time and the lowest workload, followed closely by the heads-down electronic map and the heads-up turn-by-turn display. Subjects reacted faster to the scanning task with heads-up turn-by-turn display compared to the heads-down turn-by-turn display. The heads-down electronic map despite its complexity performed better than the simpler heads-down turn-by-turn display.