The MOVA (Microprocessor Optimised Vehicle Actuation) signal control method has been applied to a wide range of independently operated signal-controlled junctions. It was designed by the Transport Research Laboratory (TRL), and its microprocessor analyses sensor data from traffic lanes, and controls signal timings to optimise delays and stops. If any approach becomes oversaturated, capacity is optimised. This paper presents the results of tests by the TRL to incorporate in MOVA features that cater for emergency and/or priority vehicles, such as buses. The facilities were tested at two bus-priority sites in London and one at Winchester. The operation of MOVA's priority-stage demand feature is subject to user-selectable and/or traffic-related constraints. A priority demand can lead to: (1) a stage truncation, ending the current stage as soon as is feasible; and (2) stage skipping, by omitting all stages between the current stage and the priority stage. Some of the constraints on priority demands depend on the previous history of truncations and skips by earlier emergency or priority changes. The MOVA version incorporating bus priority was installed successfully at the three test sites, giving varying degrees of improvement. It has been found possible to provide active bus priority within MOVA.
Samenvatting