Urban Traffic Management and Control UTMC systems : user's view of network management.

Priority (Red) Routes in London have been carefully designed, by the Traffic Director, to optimise use of the existing carriageway space using a variety of traffic management and control strategies. Within this overall objective there are increasing demands for bus priority facilities, for air quality issues to be addressed, including a desire to limit the contribution to pollution from vehicular emissions, to consider the needs of vulnerable road users, such as cyclists, pedestrians and those with mobility impairments. There is also a desire to operate highways in a more flexible manner, to achieve differing objectives, by time of day, according to prevailing conditions, or in response to changing policies. to changing policies. The Traffic Director is also required to monitor the operation of Priority Routes and to maintain the benefits which arise. Suitable tools are urgently required, to allow him to exercise control over the network according to operational objectives or should problems arise (including provision of expert systems to advise). It is also dependent upon the availability of accurate traffic and environmental information, real time and historical. Many traffic control and management systems have been developed with minimal flexibility and cannot easily be manipulated to achieve objectives. New strategies are being developed, but not necessarily with flexibility and compatibility in mind. This paper: (1) examines the objectives of network managers, such as the Traffic Director; (2) identifies the tools required to achieve multiple, often conflicting, requirements; and (3) assesses the opportunities offered by urban traffic management and control (UTMC) systems.