In its continuing efforts to improve the country’s motorway network, Highways England’s (HE) upgrade of the M3 in Surrey and Hampshire was completed with an all-lanes running scheme that uses Wavetronix’s SmartSensor HD radar units to keep traffic flowing smoothly on the smart motorway.
On August 1, motorists on the M3 experienced the latest in HE’s ongoing plan to increase the number of smart motorways by using the latest technology, including SmartSensor HD, to increase safety and efficiency. The £174m (US$225m) project is 13.4 miles (21.5km) long and stretches between the town of Farnborough and the M25 motorway. The smart section of motorway includes an all-lanes running scheme, which turns the hard shoulders into a fourth working lane, with emergency areas placed periodically along the road. To make the roadways smarter, Wavetronix SmartSensors HD radar units are used to measure traffic flow on the motorway. The information is then used to raise or lower the speed limit and to open or close lanes of traffic.
The ability to alter speed limits and lane placements in real time not only helps in cases of emergencies, but also prevents more standard traffic problems, including stop-and-go traffic. Used in conjunction with CCTV cameras, SmartSensor HD provides the input for the system. HE chose the SmartSensor HD units because, unlike inductive loops that are installed in the pavement, HDs are mounted above road, meaning road workers can deploy them safely off the highway. They also require little or no maintenance, saving money and time, as well as helping HE to move toward its ‘Aiming for Zero’ goal, where no road workers are killed or seriously injured on the country’s strategic road network (SRN).
Wavetronix’s SmartSensor HD operates at 245MHz, to produce clearer radar images for greater accuracy. To detect accurate per vehicle speeds, each SmartSensor has two HD radar beams. By timing how long it takes for a vehicle to go from one beam to the next, the unit can replicate a speed trap for every lane on both sides of the highway, replacing at least two loops per lane. It is also able to determine direction of travel, for applications such as reversible lanes and wrong-way detection.
“This project is part of the most extensive maintenance on the M3 since it was first built in 1971,” noted Shaun Pidcock, director of HE’s Smart Motorway Program. “This is a significant upgrade for the M3 and will deliver real benefits for the 130,000 drivers who use it every day.”
