In 2009, an estimated 33,403 emergency vehicles were involved in accidents, 126 of which were fatal, according to the National Highway Traffic Safety Administration. Systems are being developed to let emergency vehicles and passenger cars interact with traffic signals and other transportation infrastructure in ways that get emergency crews on-site quickly while safeguarding other motorists. One such project, for example, seeks to make intersections safer, while another will alert motorists when an emergency vehicle is approaching.
“The bigger goal from a public agency perspective is to improve the safety drastically as well as improve the mobility,” said Faisal Saleem, intelligent transportation systems branch manager for the Maricopa County, Ariz., Department of Transportation.
Pre-empting Traffic Signals
Maricopa County is using dedicated short-range communications to improve safety at intersections. As part of a research project through the U.S. Department of Transportation’s IntelliDrive program (formerly the Vehicle Infrastructure Integration initiative), the county is equipping six intersections and numerous emergency vehicles with technology that allows them to exchange information.Emergency vehicles currently use infrared light to pre-empt traffic signals, which Saleem said is basically like a remote control. A flashing light above the traffic signal indicates that the request has been received. But there’s an issue when more than one emergency vehicle tries to pass through the intersection. “It is on a per vehicle basis,” Saleem said, “so if there are two vehicles approaching the intersection from two different directions, there have been cases of collisions because each one is expecting that they will get the pre-empt.”
Maricopa County’s project — which began three years ago and involves numerous agencies, including the Arizona Department of Transportation, the University of Arizona, Arizona State University and private partners — seeks to create a system that will handle multiple pre-emption requests and serve them based on priority.
Dedicated short-range communications run on a frequency the FCC has allotted to transportation operations, Saleem said, and intersections and vehicles involved in the project will be equipped with short-range radios. “It gives the ability to communicate between vehicles and infrastructure at a very low latency,” he said. “In about a second, you can have about 20 messages exchanged between the vehicles, as well as between the vehicle and the infrastructure.”
Messages will request service and tell the traffic signal what type of vehicle is approaching, said Larry Head, associate professor at the University of Arizona’s College of Engineering. The university’s research has focused on how to take the vehicles’ requests and determine the best way to time the traffic signal to serve them.
“We have an algorithm that bases it on priority, arrival time, current state of the signal controller and its ability to respond to the request,” Head said. This ensures that no request will violate the minimum time that green lights are required to stay activated.
The real-world testing will take place at six intersections and was scheduled to begin in July or soon after. Saleem said the Transportation Department will examine how far from the signal the notification is received, and the processes of changing the traffic light and providing pre-emption. “Any response vehicle that is out on the roads, we are trying to see if they could respond more safely as well as reduce their response times,” he said.
The outfitted intersections also will be used as test beds for other projects, like transit priority for school buses and government vehicles.
Alerting the Public
Another transportation system being developed by two retired firefighters will interface with smartphones and GPS systems to alert drivers when an emergency vehicle is approaching. Drivers today are less aware of approaching first responders due to better insulation in vehicles and enhanced audio systems, said Juan Gutierrez, a retired Denver firefighter and president of B&C Electronic Engineering.“Emergency vehicles show up out of nowhere and all of a sudden people get scared to death and try to do the best they can,” Gutierrez said. “But by the public not getting out of the way, we’re increasing our response times. It’s causing a lot of accidents across the United States, many of them fatal.”
Gutierrez and Vice President of Engineering Carl Johnson are creating 911 Emergency and Traffic Alerts (911ETA), which use automatic vehicle locators already installed in many emergency vehicles and tie that information to personal navigation devices and smartphones. “We know your location and we know the location of that responding vehicle, and we sort of combine the two,” said Johnson, who retired from the fire department in July.
911ETA interfaces with a department’s computer-aided dispatch system, and will be a downloadable application people can install on their GPS or smartphone. The app, which isn’t publicly available yet, maintains a 1,000-foot bubble around the person’s vehicle. If an emergency vehicle enters that bubble, an audible alert tells the driver what direction responders are approaching from.
Gutierrez and Johnson want to make sure this technology benefits everyone. “After meeting with and speaking to people in the deaf community, it became very clear that this is the only — and first — device to really get them ample notification of emergency vehicles,” Gutierrez said. In addition to an audible message, smartphone alerts will have a distinct vibration pattern so the user can distinguish the alarm from a phone call.
The West Metro Fire Protection District in Colorado has beta tested 911ETA since September 2010. The district’s chief, Doug McBee, said it has tested well on a number of smartphones and hasn’t been intrusive on the computer-aided dispatch system.
The company, Gutierrez said, is preparing to offer the app to the public in the West Metro District’s area, and B&C is working with vehicle manufacturers, and cell phone makers and carriers to automatically include the technology in in-car GPS systems and smartphones.
“If the public knows where we are and they know how we’re responding, hopefully they will take appropriate action,” McBee said, “and it won’t be right when we’re on top of them that they finally realize they have a fire truck directly behind them.”
Like-Minded Thinking
These two systems have at least one similar tool in mind for the future: A real-time map that will show first responders the location of other emergency response vehicles, Gutierrez said, so they can see whether they’re convening at the same intersection.Head, from the University of Arizona, said research must be done on human factors, like how to make drivers aware of the information. But it would be possible to display the information to increase safety. “The driver of a fire truck is a very busy individual, and their vigilance is looking out for traffic and doing the task of driving,” he said. “Looking over at a computer display or something may not be part of their job; we may have to have somebody else on the vehicle helping them. We’re not sure about all that yet.”
These two projects provide insight into the future of public safety for government and the public. Adding technology to transportation systems and taking advantage of existing technology can provide efficiencies and new ways of thinking for emergency vehicles.
