Like a washing machine; Most traffic signals run through their cycles with little sophistication

When Greg Pieper goes to traffic signal industry seminars, hewaves a device about the size of a pack of cigarettes at hisaudiences and boasts about its power and sophistication.

That device, he says, outperforms the contents of refrigerator-sized cabinets that control thousands of the country's 300,000traffic signals. Despite his efforts, "There's no market for mystuff because I can't get it specified." Most traffic engineers, hesaid, "are specifying things that worked 30 years ago."

Pieper is vice president of sales for SmarTek Systems, anAnnapolis, Md., company that makes vehicle detection systems. Hisview parallels that of other suppliers who are frustrated with theslow pace of adoption of new technology.

Thus, signals are cruder than many motorists might imagine, goingthrough their repeated cycles like so many sets of washing machines.

The timing of those signals is preprogrammed on a signal-by-signal basis by technicians who plug in historical information. Thatusually requires a visit to each signal, an expensive and time-consuming process.

Only recently has it been possible for the city of Vancouver toremotely switch the programming of some of its signals. That's whydowntown signals have been changed to flashing four-way reds late atnight.

Those signals lack the pavement-embedded loop detectors thatallow more modern equipment to sense the presence of vehicles andquickly provide a green light. Normally, those loop detectors areactivated only when traffic is light.

In a busy corridor such as Mill Plain Boulevard, signals may besynchronized, their timing calibrated so that a vehicle traveling,say, 24 mph, will encounter a series of lights that turn green asthe driver approaches. But those signals don't know that a car iscoming. The signals have been told, through their programming, thatcars should be coming.

The problems start when something disrupts the traffic-flowpatterns to which the signals are timed to respond. An accident, badweather or a mass of cars leaving a large event can all ruin theflow of traffic. Meanwhile, the synchronized signals obedientlyfollow their electronic orders, marching at the same coordinatedpace, even if traffic is not.

Signals get messed up in another way: when emergency vehicles pre-empt lights to turn them to green. Every pre-emption scramblessignal coordination for as long as 10 minutes. Even more disturbingto traffic managers is motorists who illegally use signal pre-emptors, bought on the Internet, to speed their own commutes. "Wehave had signals pre-empted as many as 18 times in one hour whenthere was no record of use by an emergency vehicle," said AliEghtedari, city of Vancouver's traffic engineering manager.