Graphical Traffic Information on Dynamic Information Boards
TSAVACHIDIS M and KELLER H, Technical University of Munich, SCHCINFELD G, BMW Group and REISCHL A, TRANSVEK, Germany
Since the introduction of variable display technologies in traffic, a large variety of different types of dynamic systems have emerged. These include re-routing with pictograms or text, or purely descriptive textual information of qualitative or quantitat
Since the introduction of variable display technologies in traffic, a large variety of different types of dynamic systems have emerged. These include re-routing with pictograms or text, or purely descriptive textual information of qualitative or quantitative type. As contents and form of information or advice vary, so does the effect on route choice and system performance.
In Germany and other Western European countries collective systems to in- fluence drivers' route choice have been primarily of mandatory or advisory nature. Information has been given mainly to explain variable speed limits or re-routing advice information and thereby increase the system's acceptance. The information given e.g. in German speed control and re-routing systems is limited to the qualitative traffic state and immediate safety risks, e.g. due to bad weather or road conditions.
Although such systems have proven to be very comprehensible, driver's ac- ceptance of re-routing advice is not always as high as desired. This can partly be attributed to the roughness of the information given. There is evidence in various studies (e.g., Khattak etal., 1993; Wardman et.aL, 1996) that addi- tionally informing drivers e.g. on the exact location, length or cause of con- gestion can substantially effect route decisions.
In contrast to other European countries like Great Britain, the Netherlands, Italy or France, text type VMS are still sparse in Germany, where route guid- ance is exclusively done through non-textual variable direction signs. With new technologies like the internet, Digital Audio Broadcasting or in car navigation, already a new era of traffic information has opened up, using graphical network representation next to text and symbols.
The new collective traffic information system that is being developed and im- plemented within the MOBINET project uses dynamic graphical traffic infor- mation and is in its form unprecedented in Germany but also in the whole of Europe.
Japan pioneered in using collective type graphical information displays (Ta- keda et al., 1999) al. The results cannot be directly transferred to the Euro- pean environment, though. Due to completely different nature of script, peo- ple's perceptive capabilities in reading graphical information must be assumed to differ largely between Asia and Europe. The use of graphical networks on collective information boards is therefore still mostly unknown territory in the western world and detailed knowledge on recognition and understanding of graphical traffic information is sparse or non-existent.
To gain knowledge on important cognitive aspects, various techniques of laboratory research including questionnaire surveys and driving simulation were used in MOBINET.
Association for European Transport