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Summer Science Exhibition 2011

Traffic control









The Royal Society, London, 6-9 Carlton House Terrace, London, SW1Y 5AG


21st century traffic control: the invisible referee


Much of our road network is monitored by space-age "Control Offices". These are the invisible "referees" that aim to smooth traffic flow, for example, by varying the timings of traffic lights.

The research behind this exhibit is in the mathematical models that are used to predict how traffic jams build up - and how these are used to program Control Office computers in order to keep the traffic flowing freely. At this exhibit visitors can explore the world of such "Intelligent Transport Systems" – and take the controls in a variety of interactive games to discover if you can smooth the traffic better than the scientists!

How does it work?

Intelligent Transport Systems (ITS) is an interdisciplinary research area, which employs cutting edge sensing, computing and communications technology in order to monitor and improve traffic flow. The research is in ITS broadly and the mathematical modelling of road traffic that underpins ITS applications.

This is an inherently complex area in which drivers attempt to optimise their individual journeys - but their interactions with each other and with the network can lead to surprising outcomes: the famous "Braess Paradox" describes how congestion can sometimes get worse following an "improvement" in the road network - and on the motorway, large-scale "phantom" traffic jams can emerge counter intuitively from instability in the short-range interactions of drivers. This exhibit reports on two recent strands of research; how dynamic speed limits stabilise motorway traffic flow and increase capacity, and how artificial intelligence may be used to adapt the settings of traffic lights. A microsite to accompany the exhibit is also available.

See all exhibits from 2011

These videos introduce some of the work to be presented by this exhibit (3 mins)

Traffic control The Royal Society, London 6-9 Carlton House Terrace London SW1Y 5AG UK