Zipper Merge Traffic Management

An innovative detection system uses SmartSensor HD’s true high definition radar to combat traffic bottlenecks caused by vehicles forced to merge due to lane closures.

Project Team

Far Data, Ltd., GLP of Poland; and the Transport Research Centre, a company that operates as part of the Czech Republic’s Ministry of Transportation.

Project Scope

Far Data and the Transport Research Centre joined forces to create a system to prevent traffic bottlenecks at locations where road construction or unplanned incidents, such as accidents and stalled vehicles, cause lane closures that require traffic to merge. The system, known as CONGMAN, uses SmartSensor HD’s true high definition radar to monitor vehicle volumes and speeds and lets drivers know the best place to merge in order to keep traffic flowing.

Problems and Challenges

Departments of transportation often rely on zipper or late merging to manage lane closures. Zipper merging requires drivers to stay in their lane until it ends, but this can cause bottlenecks, especially if traffic is heavy. Bottlenecks lead to inefficient traffic flow and dangerous driving conditions.

Knowing the best location for vehicles to merge requires accurate speed, volume and lane occupancy data, and drivers need to be informed immediately when and where to merge. A reliable system needs accurate vehicle detection that is portable and easy to configure; and an effective way to inform drivers.

Solution

The CONGMAN system utilizes two SmartSensor HD units on portable trailers: the first sensor is located at the merge point to measure flow rate and vehicle speeds; the second sensor is installed along with an LED display sign at a spot approximately 1,000 meters ahead of the merge point. Based on the data collected by the HD units, drivers are informed of the ideal location to merge via the LED display.

The system responds to a minimal speed of 50 kph (31.1 mph) and updates its data inputs every 30 seconds. The system can be controlled remotely and can operate in either automatic or manual modes depending on conditions. Communication between the devices is performed wirelessly and IP cameras and weather stations provide additional information about road conditions.

“The system uses real time traffic flow and vehicle speed data to inform drivers. Drivers know if they should remain in the ending lane, or if they should proceed to merge fluently without reducing speeds and interfering with drivers in the continuous lane.”–HUBERT NAGORNY, MANAGER OF FAR DATA’S SALES OFFICE IN WROCLAW, POLAND

Benefits

The CONGMAN system has been used with great success in the Czech Republic and in Poland. According to Hubert Nagorny, manager of Far Data’s sales office in Wroclaw, Poland, the system is able to control traffic flow without queues longer than one kilometer for up to 2,000 vehicles per hour.

“So far we have been very pleased with the system,” Nagorny says.

Nagorny says the non-intrusive SmartSensor HD is easy to set up and is more reliable than video cameras in difficult weather and lighting conditions.

“It’s worth pointing out, too, that the sensors can measure 10 lanes of traffic simultaneously,” says Nagorny, “and they provide accurate traffic parameter measurements including classification of vehicles and vehicle speeds.”