This study makes a first estimate of the possible positive and negative safety effects of navigation systems in cars, and also the safety demands that can be made for these systems. The study consists of a brief review of literature, among which a recent test of several navigation systems. Furthermore, a number of simple calculations of the (safety) effects were performed, and a small-scale survey was held among car drivers (n=130) with navigation systems. They participated by completing the survey form on the SWOV website. The literature, the test, and the survey showed that, as far as the interaction between human and machine is concerned, improvements can be made. The way of programming is not always very logical and user-friendly. The systems show little uniformity and there is no (complete) harmony with the conventional route information of signposting and radio information. The screen on which the route information is given is usually not integrated in the instrument panel, but is situated on the middle console, or even at the bottom. Most systems allow manual programming by the driver while driving, only few systems have the possibility of verbal programming. Among other things, the survey also showed that almost all drivers use the system when the route to the destination is unknown. However, the routes advised are not always judged as `optimal'. The calculations are based on an optimal scenario, in which all passenger cars are equipped with a perfectly designed navigation system. An important result of navigation systems is that less detour (i.e. unnecessary) kilometres are driven.
Abstract