Driver information needs and ITS

Intelligent Transport Systems (ITS) collect, modify and process huge amounts of information on which different services are based. Usually, the aim of ITS is to improve traffic fluency and safety. This presentation focuses on informative systems. The driver's basic task is to drive the vehicle safely from A to B. It has been suggested that information processing in the driving task should to be studied at three levels. The levels include the strategic, the tactical, and operational control of car driving. The information needed for decision making is different at each of the three levels. Furthermore, for each driver sub-task, there are specific needs not only for information content but also for quality of information and the human-machine interface (HMI). It is axiomatic that at all levels the information provided must meet some quality requirements such as being reliable and consistent. In the following, some potential information needs and information provided by ITS for driver decision making are discussed for the strategic and tactical levels of driver behaviour. On each level the information may be obtained from the driver, the vehicle, the environment and other road users. It seems that information provided by ITS on the strategic level is useful and increases efficiency in driving and systematic use of information. This decreases memorising and uncertainty while driving and at its best de-allocates information processing capacity for the primary driving task. The effective use of information supports safe, efficient and sustainable driver behaviour. The tactical and operational control levels are based on data on the immediate driving environment. Most of the information at tactical level is obtained visually and there is a danger of information overload. Increasing the information processing workload while driving is questionable. Especially when information is provided while driving it should be asked in which way the information supports safe driving, and whether the information provided loads the driver too much or improperly. To summarise, information provision at the strategic decision level is favourable, and there is room for more information and more efficient use of information. At the tactical decision level information provision does entail some risk, and it should be considered very carefully whether new information is really needed. The hierarchy in the model presented by Michon (1985) assumes a dynamic relationship among concurrent activities at the strategic and tactical levels. Consequently, the information provided (before or during the trip) may have more substantial and widespread effects on driver behaviour than expected. The criteria for information provision and also ITS in general should be the welfare of people. In addition to the expressed needs of individuals the welfare of the society has to be assessed. The welfare can be improved in different ways. However, it is obvious that if ITS reduces traffic safety markedly, it will not increase the welfare.