This paper describes the background, objectives, features and current status of implementation for a motorway monitoring and control system, CITRAC 3, for Glasgow. The design and implementation was made more complex a) because it was replacing an existing system - which had to be maintained operational; b) the need to design a fully integrated system which incorporated the features of other systems (e.g. FEDICS); and c) the broader objectives of the Scottish Office to establish a national driver information and control system. (A)
Abstract