Are safety and performance affected by navigation system display size, environmental illumination, and gender when...

Driving with the aid of a navigation system could distract drivers. A high level of distraction influences driver performance and safety, leading to a possible increase in road crashes. The illumination level and size of the GPS display may influence the duration and frequency of a driver's glances, which in turn may affect driver distraction. In a simulated driving experiment requiring the use of a GPS, the GPS's display size and illumination level were examined, in light of the driver's experience and gender, to understand their effects on the performance and safety of young drivers on roads in urban and rural areas. Twenty young subjects, male and female between the ages of 18 and 29 years, participated in this experiment. Driving safety was evaluated by lateral control (number of pavement and lane line crossings), number of crashes, number of near misses, and the total time out of the lane. Driving performance was evaluated by the number of navigational errors, the total time making navigational errors, number of times the speed limit was exceeded and total amount of time speeding. These measures were analyzed using a repeated measures analysis of variance (ANOVA) model. Furthermore, the effects of the GPS display, considering the driving experience, were investigated with a simple linear regression. Findings suggest that driving with a small GPS display in an urban area leads to more navigational errors than driving with a large GPS display. Furthermore, more speed limit violations tend to occur in rural areas in the daytime than at night. Moreover, in urban areas, male drivers tend to have the highest number of crashes during the daytime. Furthermore, in rural areas, males tend to violate the speed limit more often and for longer periods of time during the daytime than at night and more than females do. Additionally, when navigating with a GPS system, young experienced drivers drive safer than inexperience drivers. The findings are of interest to designers and transportation researchers concerned with improving GPSs to enhance driving safety and performance.