Integrated Traffic Management - Dealing with the Dynamics of Large Computer Systems
ROOZEMOND D and JOHANNS R, Delft University of Technology, The Netherlands
Current estimates are that 65 percent of peak-hour travel on highways and urban roads and 10 percent of all daily urban travel is conducted under congested conditions. The inability of the existing road network to cope with increased demand has been ident
Current estimates are that 65 percent of peak-hour travel on highways and urban roads and 10 percent of all daily urban travel is conducted under congested conditions. The inability of the existing road network to cope with increased demand has been identified as one of the most pressing infrastructure issues of the decade. Past custom to counter increased congestion with more and wider roads, is currently giving way to more complex management and control systems and road pricing policies.
Under pressure from still increasing traffic related problems, modem traffic management professionals and policy makers turn to new, better traffic management systems. Most of these systems are designed and build to solve a specific problem particularly well. This research project, which is part of the research program IDEE (Integrated Disciplines Engineering Environment), deals with the pre-requisites of integrated and dynamic traffic management systems. In recent decades traffic problems have become both a social and economical embarrassment: congestion, deteriorating road safety, regression of mobility and environmental effects of traffic are widely considered important issues. A probable cure is to build more and safer infrastructure, but this is considered unacceptable as a long term solution due to limits of available space, limited resources and limits to further environmental strain such as air and noise pollution. Alternatively reduction of traffic or inhibitive costing measures could be considered. As transportation is singularly vital to the survival of cities, and widely accepted as a crucial economic factor, a system of improvements to traffic management arises as the only acceptable form to resolve the social and economic dependencies on transportation in our part of the world. A more efficient use of existing infrastructure may gain time in which to develop alternate modes of transport and/or infrastructure. As with all demand-supply problems, solutions made through traffic management can be viewed as either increasing capacity to meet demand or modifying demand to levels deliverable under certain conditions. Both views rely as much on the actual transport conditions as on the perception of those conditions by the road user. A definite advantage can be gained by making the right kind of information available to the right kind of users. This requires the exchange of information between the road system managers and groups and individuals of the public.
The function of traffic management systems is to efficiently manage existing transportation resources. The goals of traffic management systems are to maximise safety and transport productivity; minimise congestion and damage through incidents; distribute information on traffic-conditions, road-conditions, weather, etc. A TMS should invoke appropriate intervening action when undesirable situations arise. Some constraints apply to the development and invocation of new traffic management systems. The most important one is sustainability. The applicability of traffic management and traffic control systems greatly depends on their capability to react on traffic patterns and mutations. Therefore flexibility and adjustability are important aspects. Economic viability of the system or systems is greatly increased with reuse of existing installations and infrastructure. This partly depends on the use of current technologies and technology independence of design features of the systems. Existing investment can be protected by regarding the current infrastructure as a skeleton system in need of an upgrade. Social acceptability of investments is influenced by funding, largely public, and privacy issues. There should be adequate measures against misuse and the privacy of traffic participants should be protected.
Aim of this project is to develop insights into the applicability of autonomous and distributed artificial intelligence systems in the domain of traffic engineering. In this project the integration of traffic management systems is proposed. Integrating not only the traffic management and control systems, but including active participation of policy makers and traffic participants. This goes beyond the scale planned for the implementations of dynamic traffic management and control systems as IVSI-I and ATT/Drive. To handle the dynamics of the large and complex system several specific subjects will be researched in depth. In this paper we investigate the possibility of using autonomous intelligent management systems to cope with the workloads of traffic managers and control operators, while maintaining high levels of usability. We demonstrate that an integrated dynamic traffic management and control system can adapt and respond to traffic conditions in real-time and maintain its integrity and stability within the total system. Current traffic models do not sufficiently account for the specific problems in urban traffic following from small scale interactions. An example of Urban Traffic Control is included to illustrate the possibilities presented by integrated dynamic traffic management systems.
Association for European Transport