Houston is installing systems at intersections that will allow traffic lights and vehicles to communicate with one another in real time. Based on a far-sighted traffic management program being developed by the U.S. Department of Transportation, these steps could set the stage for new services based on oceans of vehicle-generated data that would optimize traffic flows, accelerate emergency response, reduce collisions, and minimize noise and pollution.
Houston, Texas. A major storm is approaching. Vast areas are expected to be flooded. Evacuation measures are in full swing. Yet traffic is streaming out of the city in an evenly-distributed pattern under a menacing gray-green sky. In a haze of red and blue lights, the occasional ambulance or police car flashes by. As if by magic, the traffic lights at intersections turn green each time an emergency vehicle approaches. Everything moves according to plan. No one wants to revisit the 2008 nightmare that was Hurricane Ike.
Can a major metropolitan area be evacuated as smoothly as this scenario suggests? Harris County, a 4,500 square-kilometer (1,700 square miles) area that includes greater Houston and, with over four million residents, is the third most populous county in the U.S., is implementing a pilot plan that may set the stage for a revolutionary way of managing traffic not only during emergencies in southeast Texas, but year round throughout the United States.
The plan makes use of technologies now being developed as part of the United States Department of Transportation’s (DOT) IntelliDrive™ program, a research initiative focused on the creation of safe, interoperable connectivity among all types of vehicles, the traffic management infrastructure, and mobile devices. And Siemens, which is the market leader in traffic management technology in the U.S. and a major supplier to the world automobile industry, is a key player.
During the plan’s first stage, which has already been largely implemented, Siemens Mobility Division’s Intelligent Traffic Solutions (ITS) business in Austin, Texas is equipping approximately 400 intersections throughout Harris County with a simple, inexpensive control system that dynamically alters traffic light timing based on an algorithm that estimates the number of vehicles approaching an intersection at any given moment. To do so, the technology uses a Linux-based computer, an antenna and a wireless radio reader card to tap the anonymous addresses of smartphones in nearby vehicles. “
A study in which our pilot system was installed in the same boxes that house toll tag readers in Houston produced basically identical travel time estimates — without any of the expensive tolling equipment,” says Siemens ITS Innovations Manager David Miller. “It takes only a few cars with smartphones on standby to produce highly accurate estimates of vehicle densities and speeds.”
The data from phones is aggregated using a unique application funded by the USDOT and developed by the Texas Transportation Institute at Texas A&M University that runs on software developed by Siemens Corporate Technology in Princeton, New Jersey. Siemens signal controllers at intersections throughout the county process the resulting information to produce highly-accurate real-time estimates of the number of vehicles on the road and their speeds, all of which is mapped onto a geographical database accessible to drivers via smartphone. During an evacuation, this system would allow each driver to choose a route with the shortest travel time, thus conserving fuel, which can quickly become scarce under emergency conditions, and effectively dispersing traffic instead of concentrating it on congested evacuation routes.
What’s more, Siemens’ traffic signal controllers throughout much of Harris County have been networked via fiber optic cables and connected to Siemens servers and software at Houston’s Transtar emergency management center. “Taken to an extreme, the traffic patterns for the entire city could be optimized with this technology, or tailored to meet the unique needs of an emergency. This is a classic example of what we call collective intelligence — the aggregation of massive amounts of data to produce information that can drive new services,” says Justinian Rosca, who leads the project’s software integration team in Princeton and, together with Miller, has filed a number of related patents.
Priority Treatment for First Responders. What’s next? Assuming it receives funding, Harris County plans to outfit its roughly 2000 public vehicles — everything from ambulances and police cars to fire trucks and buses — with GPS radio devices that communicate with the newly-installed intersection control technology using a standard frequency. “One of the lessons learned from Hurricane Ike was that different districts in Houston had different communications equipment that was not interoperable,” says Miller. “Clearly, with interoperable equipment, comprehensive evacuation coordination would be improved.” Setting the stage for accomplishing this is the recent adoption by the U.S. Federal Communications Commission of a standard in the 5.9 GHz band for high-speed vehicle-to-vehicle and vehicle-to-infrastructure communication as part of the IntelliDrive program.
Known as Dedicated Short Range Communication (DSRC), this development will make it possible to produce standardized onboard equipment for emergency vehicles. “The equipment has a range that exceeds a quarter mile (400 meters). It will send its GPS location via DSRC to an application in an intersection controller indicating that the approaching vehicle should receive priority,” explains Miller. “The application is able to read approach direction and speed, allowing the signal timing to initiate a green light regardless of the speed of the approaching emergency vehicle.” The solution will not only ensure that first responder vehicles have interoperable communications with the fixed infrastructure, but is expected to cut travel time for such vehicles while reducing the risk of collisions at intersections. Siemens is now developing such a device for research purposes for the DOT. If approved, it will enter a DOT “qualified products list” for extensive testing and eventually head for commercialization.
Primed for ITS Technologies. After the destruction caused by Hurricane Ike, it’s easy to understand why Houston would want to do its best to prepare for the next big emergency. But what’s driving the U.S. Department of Transportation to embrace the IntelliDrive concept? “For the last 60 years, our whole philosophy in the U.S. has been ‘build more roads,’” says Christy Peebles, who heads Siemens’ Austin ITS operations. “Now, American cities are out of space and are under pressure to reduce pollution, noise, and, above all, improve safety. So all of the pieces are coming together. The U.S. is therefore primed for ITS technologies.” She explains that car-to-car data links designed to automatically track frontal and rear proximity, for instance, are already helping to avoid accidents in situations where humans cannot respond with sufficient speed. “But the missing piece of the puzzle is vehicle-to-infrastructure communication,” she says. “That holds the potential for radically reducing intersection collisions, optimizing traffic flows, and improving fuel economy. The car manufacturers want it because they expect its safety features to generate demand. And they are pushing for it through the Department of Transportation.”
And Siemens is in an excellent position to provide what’s needed. For instance, in an October, 2009 field trial in Palm Desert, California, Siemens (supported by Corporate Technology teams in Princeton, New Jersey and Vienna, Austria), BMW and the California Department of Transportation demonstrated a fully-functional DSRC system, including roadside traffic signal controller, software, wireless gear in the car, and the message set — in short, all of the vehicle-to-infrastructure technology — from Siemens. The signal controller constantly compared the approach distance between a BMW 7-Series and the traffic signal. “As we approached the intersection,” recalls Miller, “we could see the traffic signal represented on the dashboard in a countdown format: ‘I’m green, but in five, four, three, two, one seconds I’ll be red.’” Because the car and the traffic light timing system were communicating in real time, Miller explains, the car knew it could not go through the light. As a result, it shut off its engine at the optimal moment for saving energy and used regenerative braking to recharge the battery, while the battery was used to keep cockpit systems running. “In addition,” says Miller, “the traffic signal controlled the cabin temperature. It knew how long the wait would be, so it regulated power-hungry systems accordingly. Then, two seconds before the light turned green, it switched on the engine.”
Traffic Lights that Talk to Your Car. Traffic lights that not only talk to your car, but optimize its functions? The technology used in Palm Desert has been verified to result in up to a 15 percent improvement in fuel savings on manual-shift BMW vehicles, which automatically turn off their engines while the clutch is depressed. But the advantages don’t stop there. Thousands of people are killed or seriously injured each year in so-called “T-bone crashes” when a car runs a red light and plows into another vehicle. But if intersection-to-vehicle communication becomes a standard feature, such accidents would practically disappear. “If, for instance, a light is about to turn red and a car is approaching it at high speed, tomorrow’s intelligent intersection will respond in one of two ways,” says Peebles. “It will either force the car to stop, or it can hold the light green — as it would for an emergency vehicle — and allow the violator to go by.”
Sound like Big Brother? Maybe. But as Peebles points out, “It’s great to know that your kids are going to get to school more safely. And red light management is one of the many ways that IntelliDrive and Siemens technology will support that.” By the same token, this technology — when networked throughout an urban area — can ensure that priority vehicles get through in the shortest time and can take the shortest routes. In this case, the vehicle-to-infrastructure system will know which route an ambulance, police car or fire truck, for instance, will be taking, and will clear traffic along the way in advance — something that’s safer for everyone, according to Peebles, “because there are lots of emergency vehicle-related accidents.”
On a more prosaic level, the technology could go a long way toward keeping buses on schedule because the infrastructure will know if a bus is running late and will give it more green lights, if needed, to keep it on schedule. This would, in all probability, help to improve ridership. But one of the biggest selling points of IntelliDrive technology — and a possible significant source of revenue for Siemens — is what it means for the individual motorist. “Let’s say there are no emergency vehicles going by, the busses are on schedule, and you are alone,” says Miller. “If your car is equipped with the right device, the light will turn green just for you!” And of course, the same goes for pedestrians and cyclists carrying an IntelliDrive-equipped device. They will have the added advantage of becoming electronically visible to IntelliDrive-equipped vehicles — yet another major safety advantage.
Where will all of this take us? “I think this is going to happen quickly,” says Miller. “Once the onboard devices become available and the average driver sees that he or she can turn the light green, the technology will take off. It will make driving safer. It will save fuel. And with software upgrades it could lead to attractive new services such as reserving parking based on time-of-day and event-based variable pricing.”
Miller also foresees an effect on traffic group dynamics. “As soon as cars start to have the light-changing feature, they will start to aggregate because many vehicle navigation systems will see at the same time that a specific route is faster than another. And this will become a self-fulfilling prophecy because when a light sees a platoon of vehicles coming its way it will automatically turn green. That could be the first step toward automated driving. In other words, the system tells the cars what route it thinks is best, the cars form up and take the route, and they affect the lights. Eventually, you’ll be able to let go of the wheel!” Long before that happens, however, IntelliDrive technologies will be helping cities like Houston respond in the safest possible way to tomorrow’s storms.