Effective Urban Traffic Management and Control - SCOOT Version 4.4
D Bretherton, G Bowen and K Wood, TRL Limited, UK
The SCOOT Urban Traffic Control system is now operating in over 180 cities and towns worldwide. Since the first system was installed there has been a continuous program of research and development to provide new facilities to meet the requirements of the traffic manager. In 1997 SCOOT 4 was released which among other enhancements included logic to provide estimates of vehicle emissions and to allow information from `non-SCOOT' loops placed at or near the stopline to be utilised.
This was followed in 1998 with the release of Version 4.2 which included logic to improve the control of flared approaches and provide better recovery when SCOOT is overridden e.g. when controller hurry call is used to provide priority to an emergency or Light Rapid Transit (LRT). This paper describes the new facilities in the recently released SCOOT Version 4.4 which includes the following new facilities:
* Enhanced gating logic
* Enhanced bus priority logic which will allow differential priority to be given
* Logic to allow emissions to be taken into account by the SCOOT optimisers
* Logic to allow detector information from supplementary loops to be either added to or subtracted from the normal SCOOT loop.
* Provision of daily summary statistics on bus priority operation
* Option of removing nodes from the cycletime optimiser decision at cycle times above their required minimum
* Improved control of filter links in busy conditions
* Improvements to the split optimiser if a demand-dependent stage
Association for European Transport