Traffic sensors to ease jams

A scheme to open the hard shoulder to motorists and cut rush-hour congestion on one of the country’s busiest stretches of motorway is being driven by a significant IT investment.

The Highways Agency (HA) is using sophisticated traffic monitoring equipment, data collection and communication technology to assess the trial on the M42 in the Midlands.

Denise Plumpton, director of information at the Highways Agency, says if the scheme proves successful, the Active Traffic Management system will be extended to other motorways.

‘The M42 has sensor loops embedded into the road surface, which gauge the speed of traffic, and have been upgraded to determine when traffic speed drops below a certain point, such as 40 miles an hour,’ she said.

The sensors are placed at 100-metre intervals and transmit to the regional traffic control centre. Its bespoke Motorway Traffic Viewer (MTV) software then graphically represents traffic flow and analyses congestion.

Information is processed automatically using bespoke algorithms, and new speed limits are automatically sent to variable messaging signs. If congestion continues to build, the system sends an alert to HA staff so they can implement further action.

‘All traffic flow information is also stored in a database to allow a profile of when roads are at their busiest and where we need to invest,’ said Plumpton.

If the trial is successful, she says the HA will identify other congested parts of the road network that could benefit from the same technology.

‘A lot of the roads already have sensors built into them, but not on the hard shoulder, so we would have to install more sensors as well as next-generation CCTV cameras and variable messaging signs,’ said Plumpton.

‘The digital signs on the M42 have been upgraded to display pictograms, which could also be used to provide picture information for international visitors.’

Ruth Bridger, head of intelligent transport systems at the AA Motoring Trust, says technology will play a key role in easing congestion by making the most of existing resources.

‘The technology is certainly innovative, but I still believe there is more that could be done,’ she said. ‘The agency wanted to display alternative route information on digital signs, but decided it was too complicated, so it has not taken the technology as far as it could go.’

Forrester Research analyst Henry Harteveldt says technology will increasingly be used to manage congestion, such as by automatically varying tolls as congestion builds.

‘Technology has not exactly been neglected on highways, but agencies have been forced to invest in different ways because of the challenge of installing technology when a road is constantly in use,’ he said.

‘It is difficult to install sensors to reduce congestion when you have to take capacity out of the highway to install them.’

The Highways Agency IT in 30 seconds…

The Highways Agency has launched a £160m National Traffic Control Centre in Birmingham.

It collects real-time information from 3,750 road sensors, 700 CCTV cameras, 350 electronic roadside message signs and 1400 safety signs.

The HA also announced £490m, 10-year project to develop a national high-speed communications network. It will upgrade 28 existing networks, providing a single IP-based system linking 14,000 electronic road signs, CCTV cameras and traffic monitoring systems to its control centres.

The organisation has started the procurement process to overhaul its IT systems when two key contracts come up for renewal next year. It will replace desktops, mobile devices and servers, as well as its service desk and network.

The HA is putting IT at the heart of its strategy to ensure drivers are better informed of road conditions. In coming years, it could integrate with in-car satellite navigation devices and mobile phones and provide a web site with real time traffic graphs.

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Further reading

Road body mulls IT overhaul

GPS test may ease congestion

Highways Agency announces roads IT plan