Traffic Unjammed

At Siemens, Redesigning the Future of Ready, Set, Go

traffic lights1 flickr
Well engineered traffic- light systems keep traffic moving.
  • Why it matters

    Why it matters

    There’s more to traffic lights than red, yellow and green. An expert explains the complexities of keeping traffic moving around the world.

  • Facts


    • Siemens, which sells about 40,000 traffic lights a year, has the capability to remotely access the traffic control centers of 255 cities worldwide.
    • The traffic system of the future will communicate with vehicles via WiFi. Traffic lights will be able to recognize and avoid conflicts, like developing traffic jams.
    • No matter how sophisticated a traffic system is, it cannot prevent people from jaywalking. Germans, however, are very good at waiting for the light to turn green.
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When the Siemens engineer talks about his work, people often ask about how difficult it can be to switch something from red to yellow to green. But he says plenty of mathematics, algorithms and know-how are required at various levels to optimally guide traffic flows, as well as an understanding of different cultures.

Die Zeit: When was the last time you almost ran a red light?

Wilke Reints: I don’t remember. I always step on the brakes in time when the light turns yellow.

Do you take traffic lights especially seriously because you help develop them?

Yes, it’s a matter of professional honor. I have a running joke with some of my friends. When I’m out with them and they want to jaywalk at night when there’s no traffic, I stand still and say: “C’mon guys, you can’t do that. I’m the one who makes the lights.”

There are parts of the world where traffic lights are viewed as nonbinding recommendations…

I’ve had that experience many a time. I travel to Beijing a lot on business. It’s quite possible to get run over when you walk across the street on green there. We northern Europeans are used to being able to cross the street on green without being hurt. It’s different in other countries, but people there have also learned to deal with it.

So you’re powerless, no matter how sophisticated the technology?

The traffic concept simply has to be good enough to convince people in a given place. In Germany, you could install the most outlandish traffic light circuit and people would obey it. You could bring traffic to a standstill in an entire city with chaotic circuitry. In many other countries, people simply ignore what they feel doesn’t make any sense.

How big is your department?
About 200 developers work in my R&D departments worldwide to optimize the flow of traffic under every imaginable condition. We also run a 24-hour support center for our traffic engineers. Our employees help people solve problems with their traffic light systems by loading the data onto traffic computers. We have eight full-time employees in Munich and Augsburg assigned to our time zone, as well as about 15 employees in the individual sub-regions.

Are they all engineers?

Our developers are almost exclusively engineers specializing in computer science and transportation. Our service employees are definitely people with field experience, and in their case having an engineering degree isn’t absolutely necessary.

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