by Ryan | 16th November 2007

It’s no secret that the current traffic control light system is severly antiquated. We’ve all sat at a traffic light of an empty intersection and wondered why the light didn’t turn green. Or have been at an extremely congested intersection and scratched our heads in disbelief as only a few cars made it through each cycle. We waste hours sitting in traffic because the current traffic systems and infrastructure simply can’t handle current traffic levels. Or can they?

Most of the existing traffic systems were built in the 1960s and ’70s, when traffic levels were just a small percentage of what they are today. Computers didn’t have enough computing power to calculate complex systems to speed traffic along according to levels at that moment, so they were simply programmed to repeat in cycles. At the time they worked efficiently. With some changes to the current systems, traffic flow could be improved by as much as 95%.

Dr. Helbing, Professor of Sociology at the ETH Zurich Chair of Sociology, has researched a traffic control system that can meet the heavy demands of today’s traffic levels. His team of researchers looked at the results of optimizing specific lights to minimize traffic time. It worked well except in heavy traffic, where backups happened frequently. They also looked at a system that cleared all traffic when a certain threshhold was reached. Again this worked well but in peak traffic travel time was inconsistant. Both of these methods, on their own, turned out to be worse than current traffic systems. However, they found the strategy that worked the best was a combination of both of these methods. By using non-periodic, non-cyclic traffic lights, long queues would be released and travel times became predictable. This self-organized traffic control system would dramatically decrease traffic congestion and travel time.

Source: Science Daily
Photo: Flickr