Monday, July 6, 1992 - Page updated at 12:00 AM

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Buses In Bremerton Get The Green Light -- New System Changes Signals, Speeds Transit On Way

BREMERTON - Every impatient driver's dream must be to find a way to turn red lights green.

That technology exists now.

There's a catch, though - it's just for buses and emergency vehicles. And it promises to almost revolutionize bus travel.

Known as Opticom, the system is being installed on 40 buses and 42 traffic signals here in a yearlong test that begins tomorrow.

While many emergency vehicles have had the capacity for years, Kitsap Transit is the first mass-transit agency in the country to install a full-fledged system for buses.

A major advantage, its backers say, is that it has the potential to dramatically cut transit times at a fraction of the cost of building separate high-occupancy-vehicle lanes, which can amount to $5 million a mile.

It also extends such rapid service to city streets, where the addition of HOV lanes often is impossible.

In one test, an Opticom-equipped bus made what's normally a 40-minute run through rush-hour Bremerton traffic in 25 minutes, said John Clauson, service-development manager for Kitsap Transit who helped originate the program.

For a demonstration, Mark Anderson, operations supervisor for Kitsap Transit, drove a bus on 11th Street toward Kitsap Way.

About three blocks ahead, a red traffic light loomed above an intersection.

No problem - Anderson just flipped a switch above his head and several things happened:

-- Far ahead, a white light on top of one of the signal crossarms started blinking.

-- Then, seemingly magically, the red light turned green.

-- The bus zipped merrily through the intersection.

-- And then the same thing happened again. And again. And again.

All over town, the bus found nothing but green lights as Anderson left the system on.

"This is absolutely every driver's dream," said Clauson.

"It works so well for us, I'm impressed," he said, explaining that Opticom uses infrared waves to make the changes.

The only visible evidence of the system is an aluminum-colored strobe light on the top of the bus. About 6 inches square, the light looks somewhat like a camera flash gun or a stereo speaker.

To turn on the strobe, the driver flips a switch and the strobe flashes.

People can see that, but it's the invisible infrared beams that do the work.

Receivers on light poles pick up the beams as the bus approaches an intersection and activate the flashing white light on the signal crossarms - an indication to the driver that the system is functioning.

When the signal turns green, the flashing white light turns to a constant white. When the bus clears the intersection, the signals revert to normal within a few seconds.

Kitsap Transit started work on the installation about two years ago, with the total cost running about $250,000. Inevitably, such a system raises some what-if questions:

-- What if two buses simultaneously approach the intersection at crossing angles?

Answer: The system automatically gives a green light to the one it detected first.

-- What if a bus and an ambulance approach at the same time?

Answer: The system gives right of way to the ambulance.

-- How can it tell which one is the ambulance?

Answer: Aside from the lights and infrared beams, a computer makes the system work. The computer is programmed to tell the difference between buses and emergency vehicles.

-- Wouldn't this system really mess up synchronized traffic-light systems?

Answer: Initial tests showed that could happen - that it could take as long as nine minutes for the lights to recycle properly after a bus went through. But "we rewrote the software and now we've virtually eliminated the impact on synchronization," Clauson said.

-- Wouldn't turning the lights green for buses really tie up car traffic more by only letting two or three cars through an intersection?

Answer: It's partly to answer such questions that the test is being done, but demonstrations haven't found anything like that. One reason is that in Bremerton, the sheer numbers of buses are so small, compared with cars, that there's little immpact.

Opticom was developed by Minnesota's 3M and is sold by Safety Signal Systems of Lynnwood. The cost is being split by Kitsap Transit and the city of Bremerton.

If results of the yearlong test are favorable, it's expected the Legislature will be asked to change state laws to make the system applicable to transit systems throughout the state.

Opticom has been tried in other cities, including Los Angeles, on a limited basis with mixed results. Clauson says that's because the whole system wasn't considered.

In the Los Angeles test on Ventura Boulevard, for example, Opticom did cut bus times, but schedules weren't changed to reflect the new efficiency.

Clauson says Kitsap Transit won't make similar mistakes - tomorrow, new schedules also go into effect.

In Seattle, a limited signal-control system is used where buses exit the bus tunnel in downtown Seattle. But so far Metro has no plans to adopt a similar system in King County, partly because of costs and complications. While Bremerton has 42 signals, Seattle has about 1,000 and hundreds more are used by other municipalities in Metro's service area.

Bob White, Metro member of the regional transit project, says such systems are believed to work best where there's significant congestion with fairly low actual traffic volumes. That describes Kitsap County, population 185,000, and Bremerton, which has 35,000 residents.

Copyright (c) 1992 Seattle Times Company, All Rights Reserved.


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