Japan tests congestion causes

Right: Maintaining a safe distance can help to ease traffic congestion, claim Japanese researchers

Researchers in Japan are investigating the theory that maintaining an adequate distance between cars can help to prevent traffic congestion.

The Japanese researchers led by Katsuhiro Nishinari, an associate professor at Tokyo University, began testing the theory on the Central Expressway in Tokyo and Kanagawa Prefecture earlier this month during the Japanese Ullambana festival.

The researchers took six vehicles on the road and always maintained a 40m distance between each vehicle.

Professor Katsuhiro says that maintaining a safe distance can help to ease traffic congestion, because driver’s tend to over react when traveling too close to the vehicle in front. If the car in front brakes a little, drivers in following vehicles are likely to hit the brakes with increasing force, until the traffic stops, causing congestion.

Professor Katsuhiro says that uphill starting points and tunnel entrances are particularly vulnerable to traffic jams created in this way.

After the testing, the researchers will analyze the data collected from GPS and video to study the role and connection between the vehicle distances and traffic jams.

21 August 2008