On the Road
By David Pescovitz, Thu May 20 17:30:00 GMT 2004

From Los Angeles and Seattle to Berlin and Tokyo, city planners and researchers are deploying a slew of wireless sensors, smart street signs, and real-time data services for mobile devices to help manage traffic flow and inform drivers about what they'll face on the road ahead.


Each year, Los Angeles drivers spend a combined total of 9,000 years stuck in traffic. Cell phones make it much easier to suffer through the brutal traffic jams that are the bane of city life around the world. Fortunately, wireless technology can also shorten the waiting game of freeway commuting.

The more we know about what lies between here and there, the wiser we'll likely be about our route. In these systems, sensors collect data on how many vehicles pass a given point and how fast they're moving. That data is then transmitted to a central computer server at a traffic management center. There, the raw numbers are crunched and combined with other sources of traffic conditions--police reports, for example. Finally, the real-time traffic news and suggested paths are provided to motorists via mobile data services of Web sites.

In the United States, TrafficGauge is the critic's darling of traffic information systems. Every few minutes or so, the subscription service broadcasts traffic reports from the Washington State Department of Transportation to a palm-sized proprietary device. The WSDOT data streams in from loop detectors, hexagon-shaped wire sensors in the pavement that count cars and measure average speed.

Researchers at the UC Berkeley-based Center for Information Technology Research in the Interest of Society (CITRIS) are also leveraging loop detector data for their Freeway Performance Measurement System (PeMS). They've demonstrated a traveler information system for Los Angeles that enables online users to click on two map points and instantly be told travel time then or anytime in the future based on historical precedence. In October, a PeMS study revealed the dramatic impact of a transit strike on commute times.

Meanwhile Georgia Institute of Technology researchers believe that the best way to monitor traffic may be to get stuck in the middle of it. As I previously mentioned on TheFeature, professor Randall Guensler and his team outfitted five-hundred cars with GPS-enabled monitoring devices that track vehicle speed and position. That data is then wirelessly transmitted over a cellular network to a remote server. According to Guensler, the eventual goal is to provide traffic managers with real-time data for better control of ramp metering lights and signal timing. Guensler and his colleagues are also examining WiFi as a way to bounce the data packets from car to car bucket brigade-style until they reach a cellular base station or other roadside receiver.

While these systems are certainly not lemons, the US seems to be miles behind Europe and Asia in terms of commercial deployments. For years, Tokyo's Vehicle Information and Communication System was the crown jewel of wireless traffic navigation aids. Free to anyone who buys a car navigation system with VICS capability, the service delivers various levels of traffic and parking information to the in-dash display over short-range radio transmissions, infrared beacons, and FM broadcasts.

Berlin's Traffic Management Center, or Verkehrs Management Zentrale (VMZ) may soon be neck and neck with VICS in terms of functionality. In operation for less than a year, the VMZ is a EUR 16 million joint effort between the city of Berlin and DaimlerChrysler and Siemens.

"It all started with the fall of the Iron Curtain," says VMZ director Bernd Leitsch. "The city of Berlin realized that there was not enough space or money to build new roads but they needed a way to make the traffic more fluid."

Now, the city's major roads are monitored around the clock by more than one hundred infrared sensors, several dozen Web cams, and hundreds of traditional loop detectors. If a sensor notes a dramatic change in traffic flow, it pings the VMZ's data center with an SMS. Computer algorithms then translate into forecasted travel times and alternate route suggestions that flow onto the VMZ Web site. Specific advisories are also displayed on giant LED information panels strategically located throughout the city.

"Strict measures like road closings are under the jurisdiction of the police," Leitsch says. "But we can inform travelers that it may be better to go left instead of right."

While the Berlin VMZ was under construction, another traffic management system was being put through its paces in Frankfurt. With EUR 4 million from the European Union, a consortium of companies including the Fraunhofer Institute, Volkswagen subsidiary gedas, Geotpos, and others have spent the last few years preparing their City-FCD (Floating Car Data) for prime time during the the Olympic Games in Athens this August. "Floating car" refers to a fleet of thousands of official vehicles such as city buses equipped with GPS systems and cellular links. The vehicles will navigate the jam-packed city acting as "mobile sensors," similar to the instrumented cars used in the Georgia Institute of Technology research. If they get suck in gridlock, the vehicles will send an SMS to a traffic management center. A helicopter armed with a high-resolution wireless camera can then be dispatched for further reconnaissance. SMS will also be used to provide drivers with traffic reports.

“The driver doesn’t just want to know whether or not he will be caught in a traffic jam during his journey from A to B," says gedas product manager Ralf Wilenbrock. "He wants to know how long the entire trip will take, including congestion and alternative routes."

Or, in kidspeak, how much further?