Sign In

Communications of the ACM

ACM News

Computers Guide Traffic Lights to Reduce Congestion For Commuters, Other Drivers

View as: Print Mobile App Share:

There probably are just two times when you think about a traffic light.

When one just turned yellow. ("Can I make it?")

When one has been red for too long. ("Come on, change!")

Traffic lights, on the other hand, are much more thoughtful about you.

They note the hum of your passing tires. They adjust to meet your needs. They sense your mounting frustration. It won't be long before they also know how many people are in your car and just where you're headed.

Traffic systems -- and the stoplights that are their highway sentinels -- are complex networks that must be synchronized with Balanchine precision or rush hour will descend from the normal headache into commuter hell.

Very few Montgomery County drivers even knew that traffic signals talked behind their backs until a communications glitch in November threw the whole system out of whack and caused almost two days of complete chaos on 3,500 miles of roadway.

You may not know that loops of wire under the pavement at many intersections already note the passing of every car. If you knew the sharpness of the nearly ubiquitous intersection cameras, you'd floss more often. When there's a backup, traffic systems know how many cycles it takes you get through the light.

One day not too far off, the computer in your car will deliver more useful information.

No, you're not the first person to raise the privacy issue. It's very much out there. For the moment, however, let's just look at the technology under development.

Right now you may have a Global Positioning System device that communicates with satellites in real time as you drive. Soon your car's own computer will be able to gather GPS information and data of all sorts and share that with all the cars around you and with traffic control signals.

You'll get feedback. It will warn you of dangers -- cars too close or too fast -- and suggest alternate routes when congestion lies ahead, as many GPS systems already do.

And it will give traffic flow experts a wealth of information they've never had before.

From The Washington Post
View Full Article



No entries found

Sign In for Full Access
» Forgot Password? » Create an ACM Web Account