With autonomous driving, traffic lights could become needless

Scientists are working on intelligent control systems for self-driving vehicles, in order to improve the traffic flow at crossings.

Autonomous driving: In the future, scientists intend to regulate the flow of traffic without any traffic lights. Photo: Johannes Roller

Who hasn’t already experienced this situation: You are in front of a red traffic light, although there is other car visible that could get in your way. This leads to unnecessary delays, backlogs and traffic jams. Since some time, there are control systems that work with sensors and cameras intended to avoid these situations – but it still happens far too often. First, traffic lights switch to red for all other lines when one line has green light. This means a few seconds of total deadlock. Second, there are some experts, e.g. from the MIT Senseable City Labs (Massachusetts Institute of Technology) who think that the traffic flow cannot be controlled optimally by traffic lights.

Passing the crossroads as one column
Together with some colleagues of the Instutio di Informatica e Telematica in Pisa and the Eidgenössische Technische Hochschule Zürich (ETH Zürich) the experts work on algorithms for autonomous driving that optimize the traffic flow at crossroads and should dispense with signaling installations. They already completed some models of control systems. On seems to be particularly promising: In the Batch model, when self-driving cars approach a crossing, they would be lowered or accelerated in their speed accordingly to the traffic flow via data transfer. This would lead to small columns that could pass the crossing at a stretch. The longer the column would be, the higher would become the capacity of the crossing – up to two times higher than with a normal traffic-light system. Additionally, an autonomous regulation of traffic would very effective because the individual driving style of humans would be eliminated, one of the obstructions of smooth traffic flow.

That’s all still up in the air. But the scientists point out that the traffic infrastructure installed today, will be valid for the upcoming decades. Therefore it would be reasonable to think about future ways of traffic control. As long as there are non-autonomous cars on the streets, traffic lights will survive.