“Houston TranStar’s monitoring system on I-45 between Houston and Dallas allows us to provide travel information during both evacuations and for day-to-day use at a fraction of the cost of other technologies,” said John R. Whaley, Director of Houston TranStar. “Because of the incredible cost savings involved, this technology is a game-changer in travel monitoring — whether for emergency management or daily commuting.”

The plan to monitor travel conditions on I-45 came after Hurricane Rita threatened to devastate Southeast Texas in 2005. When millions of Gulf Coast residents evacuated their homes and created a 30-mile traffic jam from downtown Houston along I-45 North, officials recognized the need for a more extensive traffic monitoring system.

The Texas Department of Transportation (TxDOT) (one of Houston TranStar’s four member agencies) and the Texas Transportation Institute (TTI) began to investigate more cost-effective solutions to capture real-time travel times and traffic speed data on rural highways. TTI, a state agency within the Texas A&M University System, found that Bluetooth®-enabled devices could be used to determine accurate travel times, and could do so in a cost-effective, non-intrusive way that protects privacy and is easy to install and maintain.

The same technology is also being used to monitor traffic conditions along the I-35 corridor during a major construction project to widen that roadway.

“The Bluetooth-based Anonymous Wireless Address Matching system, or AWAM, can typically be deployed at less than 10% of the cost of traditional toll-tag based travel monitoring systems,” said Stuart Corder, Director of Transportation Operations, TxDOT’s Houston District. “The AWAM system saved taxpayers $1.5 million and let us accelerate implementation of new technology on a major Interstate.”

Travel time information is not only available during evacuations, but is accessible 24 hours a day/7 days a week to provide current travel conditions on I-45 between Houston and Dallas. The sensors collect anonymized data that is not tied to a particular individual.  In addition, all data are encrypted upon receipt before being processed and sent back to TranStar. Travel times obtained from the AWAM system can be viewed on Houston TranStar’s website at www.houstontranstar.org. More information about the system and protection of travelers’ privacy can be found at http://traffic.houstontranstar.org/bluetooth/transtar_bluetooth.html.

The Center for Digital Government is a national research and advisory institute on information technology policies and best practices in state and local government. Houston TranStar was recognized by the Center at the state level in 2006 and again in 2011. This is Houston TranStar’s first national-level award from the Center.   TTI Research Engineer Tony Voigt added, “TTI is very proud of this award presented to TxDOT and TranStar from the Center for Digital Government.  We are grateful for the support from our TxDOT Houston District sponsors and Houston TranStar partners, and we are excited to see the system move from research to implementation.”

Texas Transportation Researcher article on the use of Bluetooth technology to gather travel time information.

A bird's-eye view of a typical rural travel-time monitoring installation mounted on a luminaire pole.

In August and September 2005, Hurricanes Katrina and Rita created many disturbing realities for Gulf Coast states, including the need for safely evacuating large numbers of coastal residents. Five years later, planning and implementation of improved hurricane evacuation information systems using Bluetooth® technology are emerging in Texas.

After these storms highlighted areas for improvement in evacuation plans and procedures, researchers at the Texas Transportation Institute (TTI) began working with Texas Department of Transportation (TxDOT) personnel on improving all transportation aspects of the evacuation process. TTI researchers Michael Vickich and Darryl Puckett have developed a Bluetooth travel-time monitoring system for supporting evacuation monitoring. By providing important data about traffic flow on evacuation routes in rural areas, the system will enable transportation officials to make better decisions during evacuation scenarios.

“Prior to this system, decision makers were put in a very difficult situation when having to choose whether to deploy contraflow or not during evacuations,” explains Tony Voigt, a TTI research engineer. “The new system will give state officials very good information about real-time traffic conditions in the rural areas on evacuation routes, including at what rate traffic is flowing, which will enable them to make more informed choices than in the past.”

Currently this system is being implemented along I-45 from Houston to Dallas, Texas. This stretch of highway is over 225 miles long and will have Bluetooth device readers placed between 5- and 20-mile intervals, but typically between five and 8 miles apart. This system will work by reading the unique identifier (called a media access control [MAC] address) that each Bluetooth device transmits within a short range as it passes by the antennas.

As vehicles equipped with enabled Bluetooth devices pass by successive device readers, the system matches the MAC addresses and then determines average travel time and speed between the points on the roadway. In an evacuation scenario, this technology will be instrumental in providing an accurate representation of what travel times and average speeds are in rural areas along the highway. With this information, decision makers can make informed decisions, such as whether or not to deploy contraflow or how to respond to incidents.

“The information this system provides for rural areas during evacuation scenarios is tremendous, but its capabilities do not end there,” says Darrell Borchardt, senior research engineer with TTI. “Travel-time information will be available 365 days a year on roadways equipped with the system, which will provide motorists current information about how incidents or other weather-related conditions are impacting travel times.”

This photo shows a close-up of the prototype monitoring equipment.

Other important benefits of this technology include a low-cost, low-maintenance way to anonymously collect travel time and speed data. MAC addresses do not contain any personal information and are not directly associated with a specific user.

“TTI‘s expertise helped us prove that Bluetooth technology can efficiently and accurately provide segment speeds and travel time data,” says David Fink, TxDOT transportation operations engineer with Houston TranStar. “The traffic information we can now gather in rural areas will better prepare us for countless scenarios — just one of which is hurricane evacuations.”

This Issue

TTI’s Research Umbrella: Safer Transportation in the Storm

Volume 46, Number 2
June 2010
Issue Overview

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• For More Information

For more information:

Tony Voigt
(713) 686-2971
t-voigt@tamu.edu

For more information on Houston TranStar, please visit http://traffic.
houstontranstar.org.

]]> http://tti.tamu.edu/2010/06/01/using-bluetooth-technology-to-aid-in-hurricane-evacuation/feed/ 0 http://tti.tamu.edu/2010/03/01/now-taking-it-to-the-streets-collecting-travel-time-data-speed-with-bluetooth-technology/ http://tti.tamu.edu/2010/03/01/now-taking-it-to-the-streets-collecting-travel-time-data-speed-with-bluetooth-technology/#comments Mon, 01 Mar 2010 18:36:29 +0000 Chris Sasser http://tti.tamu.edu/?p=1494

A screen shot of the Houston TranStar website.

You might be familiar with the name Bluetooth® as a way of wirelessly talking on your cell phone. More generally, it’s a personal area network that connects devices wirelessly over short distances.

Researchers at the Texas Transportation Institute (TTI) are using Bluetooth technology for a host of applications involving traveler information, traffic management and planning systems. Currently these data are collected using toll tags, GPS, license plate recognition and cellular phone networks, which can be expensive and inefficient. Data collection by Bluetooth presents a viable alternative.

How the Technology Works

Each Bluetooth device has a unique identifier called a Media Access Control (MAC) address, which the device transmits within a short range.

“A motorist with a Bluetooth-enabled device drives by a road sensor, and the sensor reads the MAC address,” says Darryl Puckett, a TTI research scientist investigating uses of Bluetooth technology. “Further down the road, another sensor reads the MAC address again, and the system matches it to the first reading.” Software then determines how long it took to travel from one reader to the other and calculates the average speed.

Privacy is an important concern. MAC addresses are not directly associated with a specific user and do not contain any personal information. Users can also disable the Bluetooth function of their device to prevent it from being read.

The benefits of this anonymous wireless address matching (AWAM) system are many. A large percentage of the population has Bluetooth devices, so the technology is easy and nonintrusive for motorists. The roadside readers are low cost and low maintenance, using standards-based, non-proprietary equipment and protocols.

Applying the Technology

Funding from the University Transportation Center for Mobility (UTCM) assisted TTI researchers in developing a full, end-to-end solution for AWAM, with the following features:

• roadside hardware and software for reading and forwarding MAC addresses,
• host software for calculating real-time and historical travel time and speed data, and
• analysis and graphics capability to view current and historical data graphically.

Border Crossings

The ability to accurately estimate wait times at international border crossings is one of the goals of Bluetooth technology applications.

Millions of motorists cross the U.S.-Mexico border every day, often with long delays. Current methods of determining delay — usually by visual estimates or motorist survey — are unreliable.

“Deployment of Bluetooth technology at the border is geared toward obtaining crossing times of passenger vehicles, which can then be used to accurately estimate wait times,” says Rajat Rajbhandari, TTI associate research engineer. “This project was the first of its kind to use Bluetooth technology to gather traffic information in Texas.”

Researchers collected data at three ports of entry in the El Paso, Texas, region: the Bridge of the Americas, Ysleta and Paso Del Norte. The study confirmed that Bluetooth technology could be used to measure U.S.-Mexico border crossing times. A follow-up project will deploy Bluetooth sensors at the Ysleta port of entry in El Paso and compute the crossing time in near real time.

“We’re also working on deployment of RFID [radio frequency identification] technology at border crossings in El Paso, Laredo, Pharr and Arizona to get crossing times of commercial vehicles,” says Rajbhandari. “Crossing time information for both passenger and commercial vehicles is crucial to understand the operational and planning aspects of international border crossings.”

Urban Areas

Travel time data can help commuters choose when and what route to travel and help planners identify congested segments for operational or infrastructure improvements. TTI has worked on several projects in Texas:

• Houston commuters can check the TransStar website to see how long it will take to get to work. The partnership between Houston TranStar and TTI is investigating whether AWAM can expand this coverage to arterials.
• AWAM proof-of-concept demonstrations with the City of Houston, the Texas Department of Transportation (TxDOT) and Harris County on urban arterials showed that Bluetooth device penetration is sufficient to collect high-quality travel time data.
• In a project for TxDOT, TTI collected travel times and speeds on identical roadway segments using a toll tag reader system and the AWAM system, with comparable results.
• TTI has deployed the AWAM system at several west Houston intersections to monitor travel time for a network of urban arterials.
• TTI demonstrated the AWAM system on parallel routes to U.S. 75 North Central Expressway between Dallas and Richardson.

“I see this technology as an exciting, innovative way to obtain traffic information in places where we would not otherwise be able to gather data because of the cost,” says David Fink, a TxDOT transportation operations engineer with Houston TranStar. “Other technologies can be up to eight times more expensive than using Bluetooth technology. In some cases this is just cost-prohibitive.”

The anonymous wireless address matching (AWAM) concept for travel time data collection.

This Issue

Improving Our Transportation Operations

Volume 46, Number 1
March 2010
Issue Overview