If your car is paying attention, his signal might tell you to speed up a bit so you'll make it through the next six lights without stopping.
Comstock is Chattanooga's traffic signal systems engineer, and he's one of the key people trying to figure out how to move city traffic forward until the time driverless vehicles completely change the way our world works.
Last week, Chattanooga joined 76 other cities in applying for a $40 million federal Smart Cities grant not just to design a futuristic system, but actually start putting it into place. Chattanooga's application team included the city, the Electric Power Board, the University of Tennessee at Chattanooga and the Oak Ridge National Laboratory.
Comstock believes Chattanooga has a fair chance of winning, largely because it already has much of the infrastructure in place.
"The city of Chattanooga is uniquely positioned because we have the Gig fiber network, and we have an [integrated traffic] system already, we have a good transit system," he said. "Even the Innovation District — all of this stuff ties together."
Ken Hays, president of the city-backed Enterprise Center, said he believes the grant application is a chance for the city to show what it can do with its fastest-in-the-nation Internet service.
"Chattanooga is a test-bed community, a very scalable community, where applications like this can be tested," Hays said, "both in starting to play with sensors and integrated traffic lights, and potentially autonomous [driverless] vehicles, because of our infrastructure."
Of the city's approximately 300 intersections, 200 already have been upgraded with Internet connections not much different than what connects computers in a typical office. Already, the city can run software programs that adjust traffic signals depending on the time of day and previous traffic patterns.
A next step, which already is underway, will add cameras to some of the intersections near the Highway 27 construction downtown. While the quality of the video won't allow anyone to identify the cars specifically, it will allow traffic engineers to count the number of cars and adjust the signals accordingly.
Beyond that, Comstock believes some pretty impressive feats are not that far out of reach.
"Thirty percent of all traffic downtown is looking for a parking space," he said. "If we could just tell [the cars] where a parking place is, you would eliminate that."
When there is a wreck on Interstate 24 or Interstate 75, traffic on adjoining streets such as Lee Highway or Brainerd Road comes to a standstill as drivers look for alternative routes. But an interconnected system would allow engineers to view congestion in real time and change the traffic signals over a wide area to reduce backups.
If the city wins the grant competition, a key concept Comstock wants to explore is how your vehicle and traffic signals might communicate.
If the traffic signal could determine vehicles' speeds and how far they are from the intersection, it could adjust the lights to maximize traffic flow, perhaps telling you to speed up to make the light. Or the traffic light might sense that a lot of traffic is leaving a church or high school after an event and adjust itself until the situation returns to normal.
Pedestrians would see similar benefits.
"Persons with disabilities don't always have the ability to push a button to cross the street," Comstock said. "But if they had a device on them such as a smartphone, it could be programmed such that when they got close, the signal would know that they are there and change the light."
Late-model vehicles are beginning to employ sensors that detect objects in the road and brake automatically, or tell the driver that another vehicle is in the car's blind spot. The federal Department of Transportation and major auto manufacturers already are working together to develop vehicles that can communicate with the infrastructure, Comstock said, so his future traffic control system may not be that far away.
Comstock believes the city's downtown electric bus shuttles might be a good place to start because they run a fairly simple fixed route. The driverless function would be phased in over time.
"It wouldn't be wholesale, where we would take all of the electrics off the street," Comstock said. "We would still have a driver there to ensure that it is all operating, and then wean ourselves off at some point."
All of this is a middle way along the road to fully driverless cars. Whether such vehicles will prove to be a boon or burden to society won't be known for many years, experts say.
Some see a world where parking lots could be moved to the perimeter of a city, or pushed to the backs of strip malls, and cars summoned via smartphone valet-style when the driver finishes his or her business and is ready to leave. If motorists no longer needed to drive, they could spend their commuting hours in more useful or enjoyable pursuits, while the elderly or disabled would have access to many more facilities.
Critics warn that making commuting less painful might also encourage motorists to endure longer commutes, boosting urban sprawl. Others warn that getting rid of truck and bus drivers could dump hundreds of thousands of people out of work who often have only high school diplomas.
UTC professor Greg Heath, who worked on the grant application, is optimistic.
"Urban transport systems and nonmotorized transport put us in touch more with each other and our environments," he said, "and social capital is more likely to be enhanced than with our current suburban one person/vehicle lifestyle."
We won't know who is right for many years, Comstock believes.
"Realistically, at some point, everybody is going to have an autonomous vehicle, and all of this will be taken over, like in those sci-fi movies where they have a car train of six to seven cars all traveling 60 mph, bumper-to-bumper," he said. "But that's a lot harder to pull off than they indicate there."
For Hays, what is important is that Chattanooga is starting to try to figure out how such a future would work.
"It's going to be the gigabit cities of the future that are going to answer these questions in a big way," Hays said. "With the Internet of Things and mobile devices, smart cars, smart buses — you're going to have to be a very advanced communications city, not only in the short but in the long term."
©2016 the Chattanooga Times/Free Press (Chattanooga, Tenn.) Distributed by Tribune Content Agency, LLC.
