Future directions for traffic management systems

An emerging form of traffic control system that is based on the use of microprocessors, interconnected in a local area network (LAN), is described, and its future evolution is examined. These networked systems provide the ability for multiple users to access system databases and to offer an enhanced suite of capabilities including online signal optimization, maintenance management, and traffic management. They are useful for both signal and freeway control applications. Their operation requires more sophisticated local control equipment to provide the backup and local timing features for reliable operation and to take advantage of the central system´s capabilities. The microprocessor is rapidly replacing the minicomputer as a central control processor because of its lower cost, user friendliness, and the availability of numerous off-the-shelf software packages to enhance its operation.<>