Path to safer roads takes positive turn

Nov 1, 2007 12:00 PM, By Lynnette Luna

The I-35W bridge over the Mississippi River in Minneapolis collapsed during rush hour on Aug. 1, plunging dozens of cars and their occupants into the water. The calamity put an ugly spotlight on the U.S. Department of Transportation regarding road safety, and created an urgency to incorporate technology that can help reduce highway fatalities.

One vital technology is bidirectional vehicle communications, which lets vehicles communicate with roadside devices and other vehicles to exchange data as needed. Such a capability not only could have been used to enhance traffic management on the bridge, but it also could help shrink the alarming number of traffic fatalities on U.S. roads. According to the National Highway Traffic Safety Administration, 42,642 people were killed on U.S. highways last year, an average of 3500 per month.

Experts say that taking just 10% of automobiles out of a traffic jam could increase the average speed of the traffic flow by 50%. And even if a small number of automobiles could be warned about potential congestion ahead and be diverted by either direct communications or electronic signs, it could have a substantial impact on traffic congestion. Therefore, the DOT sees bidirectional vehicle communications as having a major benefit for both safety — by pre-emptive action to avoid accidents — and for monitoring fuel efficiency and emissions.

“One of the stated goals of such intelligent vehicle highway systems is to reduce the instances of accidents,” said Dave Alexander, principal analyst for ABI Research. “The other benefit is having a lot of information about where traffic is flowing and even to the level of warning about road conditions.”

Work began on bidirectional vehicle communications in the 1990s with a focus on building systems that would enable vehicles to be operated automatically by following buried lines on the roadway. The cost, however, proved prohibitive.

Wireless technologies then were proposed to pass information between vehicles and to roadside access points. Dedicated short-range communication (DSRC), which establishes Wi-Fi data networks specifically for automotive use, enables any two DSRC-equipped vehicles to exchange data via ad-hoc networks that are created spontaneously between vehicles as the need arises. This information can include transmitting braking signals back over several vehicles, giving drivers early warning that they might soon have to brake.

DSRC spectrum falls in the 5.850-5.925 GHz band that the FCC allocated to enhance the safety and productivity of the transportation system. The American Society for Testing and Materials (ASTM) standardization committee E17.51 is developing a standard. DSRC is designed to complement cellular communications by providing very high data transfer rates in circumstances where minimizing latency in the communication link and isolating relatively small communication zones are important. DaimlerChrysler last year was the first to publicly demonstrate broadband car-to-car communication between a Mercedes-Benz E-Class vehicle and a Dodge Durango.

Last month saw the official dedication of the Connected Vehicle Proving Center (CVPC) in Ann Arbor, Mich. Designed to support the intelligent transportation and vehicle communications global development efforts of the Center for Automotive Research and the Connected Vehicle Trade Association (CVTA), this lab is expected to play a key role in validating future trends for wireless vehicle connectivity. The CVPC was launched with a $3 million grant from Michigan's 21st Century Jobs Fund, a $2 billion, 10-year initiative administered by the Michigan Economic Development Corp.

“Our long-term goal is to virtually link wireless-enabled roads, proving grounds and test tracks, independent bench test laboratories and traffic management centers with a centralized data processing, evaluation and training center through the CVPC,” said Scott McCormick, president of CVTA. Indeed, ABI's Alexander said the CVPC is the first real test of DSRC technology.