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GCN : March 2014
ment systems began taking advantage of the growing presence of smartphones to track traffic by sensing the Bluetooth sig- nals emitted by the devices. "You put an antenna at an intersec- tion or along a freeway, you identify and re-identify these signals on this unique Bluetooth Mac address and from that you can map trips that are being made and get travel times in real time," said Shawn Turner, head of the mobility division of Texas A&M's Transportation Institute. TTI developed just such a system for the Texas Department of Transportation and the city of Houston. Visitors to the Hous- ton TranStar website can view a map dis- playing in near real time current speed on major highways in the region. One problem with Bluetooth monitor- ing systems is that, like the federal Con- nected Vehicle program, they require the deployment of equipment along road- sides. "Road sensors work very well," said Jim Bak, public relations manager at Inrix, a provider of traffic data. "But you are lim- ited to where governments attach funding and the cost to install the sensors. Then the challenge is how do you scale that if you want to cover every road? It just doesn't scale. It's cost prohibitive." Turner agrees. And he thinks the fu- ture of traffic management is to be found in eliminating the roadside sensors. "A whole private industry has developed around crowdsourcing data from smart- phones," he said. "In my opinion that is going to be more prevalent than what we're doing." A number of companies -- including Google, Inrix and Nokia -- think so. They are developing models for "trading" traf- fic information with consumers. In prac- tice, consumers would launch an applica- tion on their smartphones that displays crowdsourced data about traffic flows in the area. In return, the consumer's own location information -- including speed and direction -- would be transmitted to the company for analysis and inclusion in the traffic data set. Companies are also working out similar agreements with public- and private-sec- tor operators of vehicle fleets. The smart- phone and app companies make money by selling the collected data to regional traffic-management systems. It's a deal that works well for everyone, Turner said. "Transportation departments don't have to put out for infrastructure," he not- ed. "And we've been able to rely on these private companies for data because they have the nationwide coverage that isn't there with the Bluetooth reader systems," he added. SOURCING THE SMARTPHONE CROWD "Inrix started with the idea that if you could turn vehicles into sensors, or devic- es that travel with people in those vehicles into sensors, you could get traffic not just where you install physical road sensors, you get traffic everywhere cars go," Bak said. The company built a crowdsourced traffic network by approaching the com- mercial fleet companies who all had both GPS in their vehicles and the ability to do two-way connectivity. The deal was sim- ple: Inrix created license agreements with the fleet companies. "You tell us location, speed and heading of your fleet vehicles, and we will give you traffic information in return that you can use for routing and lo- gistics planning," said Bak. "Basic crowd- sourced traffic was born." Inrix has also made agreements with auto companies -- including Audi, BMW, Ford and Toyota -- that deliver built-in computer connectivity in some models of their cars. While Bak acknowledges the value of adding smartphone apps to the crowd- sourced mix, he cautions that phone ap- plications that aren't integrated with other data sources will have severe limita- tions. With smartphone applications, he said, "you're really only getting data from people when they have your app on and they are using it in the car." As a result, systems that rely only on people who are currently using the ap- plication will have limited real-time data. "Traffic can change at a moment's notice due to the weather, accidents, whatever," he said. "You want to have real-time data, you want to have lots of it and you want to have it refreshed as quickly as possible." Inrix's data sets are comprised of ap- proximately 60 percent fleet data and 40 percent consumer data. Currently, In- rix collects three kinds of data: location, heading and speed. And according to Bak, tests have shown that the company's reports of traffic speeds are within 5 miles an hour of the actual speed 98 percent of the time. TrafficSense, a traffic data service of- fered by the Israel-based Cellint, uses a different strategy. Because the number of smartphones on the road running a par- ticular GPS-based traffic application is going to be relatively small, Cellint looked for a way to tap into the movement of sig- nals from all smartphones, though more accurately than just passively monitoring the pings from cell phone towers. Cellint's strategy, said CEO Ofer Avni, is to send cars on the road to create refer- ence databases for the cell signaling data by matching that data to precisely record- ed GPS locations. "Our cars are going on CONNECTED VEHICLE TECHNOLOGIES 20 GCN MARCH 2014 • GCN.COM due to the weather or accidents. want to have it refreshed as --- JIM BAK, INRIX