http://www.chicagobreakingnews.com/2010/05/bluetooth-technology-to-help-track-ike-travel-times.html
Bluetooth technology to help track Ike travel times Whoever thought that talking on a cell phone while driving would be considered a public service? But that will be the case in one respect starting within the next few weeks on the Eisenhower Expressway, where travel times have soared since a resurfacing project began this spring between Thorndale Avenue in the western suburbs and the Circle Interchange near downtown Chicago. To generate travel-time information on the torn-up highway, the state has hired a Wisconsin company to monitor signals sent from motorists using Bluetooth-enabled personal electronic devices such as hands-free headsets for cell phones, wireless headphones and computer peripherals. Each device has a unique identification marker that will be tracked anonymously at various points on the Eisenhower to determine travel times and pinpoint areas of congestion, according to the Illinois Department of Transportation. It's a temporary solution until new sensors are placed in fresh pavement on the Eisenhower later this year when the resurfacing project is completed, officials said. The old sensors embedded in the pavement to help create estimated travel times for drivers have been deactivated on much of the inbound Eisenhower (Interstate Highway 290), and the loop-shaped sensors will be removed soon on outbound I-290 as well, IDOT officials said. The sensors detect speeds as vehicles pass over them at numerous locations. The speeds are then fed into formulas yielding travel times that are posted on electronic signs along the highway, on traffic Web sites and broadcast on television and radio traffic reports. IDOT has contracted with TrafficCast of Madison, Wis., to capture the Bluetooth signals. Installation of the Bluetooth Travel-time Origination And Destination, or BlueTOAD, is scheduled to begin Wednesday, and the system will start operating in late May or early June, IDOT spokeswoman Marisa Kollias said. To minimize inaccuracies in collecting travel-time information, computers will filter out erroneous data, "such as a CTA train with 50 Bluetooth devices going 60 mph, and statistically provide only the highway travel time," Kollias said. The new method of tracking travel times is badly needed on the Ike because the accuracy of traffic reports has been reduced because of the loss of sensors during construction, Kollias said. There are still some sensors in the untouched lanes of the Eisenhower between downtown and Cicero Avenue, and from Interstate Highway 294 to Church Street, in both directions, Kollias said. In addition, IDOT's traffic control center is estimating travel times from downtown to Wolf Road by bridging the data on either side of the missing loops, she said. "But the reality is that there are still too many gaps west of Hillside and on the entire eastbound Eisenhower," Kollias said. "Travel times now are less accurate than before." All of the sensor data will be lost when traffic is shifted to the left lanes, she said. Traffic reporters are relying increasingly on helicopters or volunteer "spotters" who drive the Eisenhower and report back on the duration of their trips, she said. IDOT officials say motorists using Bluetooth devices need not worry about being watched by the government. The address information on each Bluetooth device is erased after a short time, and only the travel time is recorded, officials said. "We can assure the motoring public that this technology is used primarily for travel times. We are not using this to look for any specific drivers or any personal information," Kollias said. On Illinois toll roads, travel data are randomly collected from I-PASS transponders, also on an anonymous basis, to track traffic flow. During the reconstruction of the Dan Ryan Expressway four years ago, when pavement sensors also were temporarily removed, IDOT used a microwave radar system to gauge travel times. The microwave system worked like a motion detector, bouncing radio waves off passing vehicles to measure their speed. -- Jon Hilkevitch