This study was designed to investigate driver acceptance of traffic sign information provided by an in-vehicle terminal (IVT). Specifically, four message conditions were compared in an on-road field study: (a) visual sign (b) visual sign and auditory message, (c) visual sign and auditory feedback based on driver behavior and (d) visual sign and complete instruction provided for all subjects after the driver passed a test sign. The main results showed that the subjects accepted the integration of traffic sign information. For example, the subjects assessed that many aspects of the system were useful; they would like to include these aspects in the IVT if purchased; and the IVT information was reported to increase the effect of traffic signs and to improve traffic safety. The most preferred message condition was the visual sign. However, many subjects reported driving problems while using the IVT. The most frequently reported problems included unintentional speed decreases and late detection of another road user, vehicle or obstacle on the road. The main implication of this study is that integration of traffic sign information is a promising approach. Further research is needed to investigate the various effects of this kind of systems on driver behavior.
Abstract