U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
The recommendations in Chapter 3 encompass a broad array of initiatives that will individually and collectively have a profound impact on safety in the United States. Some are long term or strategic in their objectives and others are more tactical. As part of its responsibility, the scan team formed a subgroup called the Implementation Team and charged it with establishing an implementation plan for the recommendations in this report. This chapter contains the initial elements of the plan that will advance some of the team's recommendations. Others will follow as these initiatives mature in the future.
There is sufficient evidence to show that speed is a major factor contributing to major-injury and fatality crashes. Driving in excess of the posted speed or regulatory speed limit is an ever-increasing problem in both rural and urban environments. Closely related to speed is the increasing occurrence of red-light running. Both problem areas significantly affect a jurisdiction's ability to achieve its goal of improving motor vehicle safety. Other modes in the transportation corridor, such as bicycling and walking, are similarly impacted.
Most U.S. roads and streets are not designed to be selfexplaining in providing guidance or regulatory information to the driver. Everything from lane markings to guide and regulatory signs to traffic-control devices is provided to help drivers safely navigate streets and highways. While certain traffic control devices are "regulatory," they can be considered "advisory" when drivers choose to disregard them. When these devices are disregarded, the potential for serious crash events-many involving innocent second parties-rises significantly.
The human factor is the major consideration when evaluating these speed-related problems. A number of subconscious factors may contribute to speeding. For example, it is known that the power, suspension, and luxury ride of today's vehicles make it easy to drive at speeds in excess of those posted. The smooth ride, when combined with the safer roadway geometry and crosssection provided by today's modern highways, contributes to a comfort factor for driving faster than the targeted safe speed.
Another factor that contributes to both speed and red-light running is a changing U.S. culture in which many individuals are in a hurry to get from one point to another. Coupled with this trend are greater demands on the law enforcement community to address drug, crime, and homeland security issues within budget limits. With this reduced enforcement presence on roadways, the perceived risk of consequence to drivers who decide to exceed the speed limit is also reduced.
The scan team noted a high priority for speed management in Germany and France, evidenced by the support from top elected officials and decisionmakers as well as the number of routine deployments. While the degree of political and social acceptance affects the deployment level and schedule, the technology appears mature to help U.S. jurisdictions confront the problems and tragedies associated with vehicles driving over the speed limit.
Many examples of ITS technology have proven beneficial in reducing congestion and improving safety for the traveling public. One technology deployed throughout Europe to proactively manage speeding and red-light running is automated enforcement systems using photo detection and photo-radar. This will include data on both enforcement and red-light running.
Robert Bryant, Craig Allred, Robert Bertini, and Martin Knopp
ITS technologies often have evolved and been implemented with the major emphasis on traffic flow (i.e., mobility). Safety may be mentioned as a side benefit, but may not be quantified or emphasized. An example of such a service application is the use of data from inductance loop detectors for automated incident detection. These are used to alert operators in traffic management and operations centers (TMC/TOC) that existing conditions appear to match those typically associated with an incident.
In the United States, these applications have largely been discontinued because of both the high error and false-call rates from the loop data and the increasing use of cellular phone technologies by the general population. Operators simply were distracted (and frustrated) by the false alarms, and benefits of such a system were never realized or appreciated by transportation decisionmakers. Most TMCs/TOCs moved to more reliable technologies and real-time information via closed-circuit television (CCTV) and cell phone calls from travelers or dispatchers about roadway incidents.
Today's systems are less robust for prioritizing the information an operator needs to deploy response teams or advise motorists via dynamic message signs or other means. The challenge remains to manage the effective flow of incident data generated by traffic and the information that public safety operators need during the early minutes of the response where dispatch decisions on people and equipment are critical. Furthermore, for the most part, the causes and effects of such incidents are not shared with State DOT safety engineers who assess highway safety and design mitigation treatments.
The scan team was briefed on and observed a demonstration of an emerging technology developed in France to improve the integration of CCTV networks and operators for both automated incident detection and enhanced video access leading to the occurrence of the incident. Computer systems analyze video images to isolate a potential incident from a number of scenarios. Information from numerous cameras is analyzed and the operator then receives visual indicators that a particular video may include an active incident. The operator can select the video and replay the last few minutes leading up to the incident, then transport the video sequences to other dispatch operators or offline analysts. The system appears to overcome the user-interface limitations of the early systems used in the United States and appears easily configurable by the user. This technology has the potential to link to existing CCTV networks and enhance incident response and post-incident safety assessments.
Lyle Knowlton, Robert Callan, and Martin Knopp
The use of signs to inform motorists of traffic conditions have been deployed around the United States for many years. The typical application is a multiline text sign to advise travelers of an incident or conditions downstream from the sign. The signs also are used to inform motorists of public safety issues and, more recently, child abduction notifications known as AMBER Alerts. Some smaller signs are used at limited locations for lane-control indications that more graphically alert the driver to potential lane changes downstream. U.S. practitioners are making efforts to use these text-based signs more effectively by striving to remediate limitations of sign technology to convey meaningful and relevant information.
The scan team observed technologies in France, Germany, and Japan that appeared to increase the receptiveness of congestion messages in a more effective manner. In some locations, signs were observed that displayed dynamic congestion maps similar to those used on Web sites in the United States. In addition, dynamic signs were used proactively to route travelers to destinations or provide lane assignments, in contrast to the United States where signs typically display the message "USE ALTERNATE ROUTES." The team noted the use of symbols and common formatting of speeds and destinations, and believes that this practice provides a more effective transfer of messages to travelers. Further, some countries have developed protocols for displaying static and dynamic information on overhead signs.
Significant advances have been made in the development of onboard navigational systems technology to provide real-time information to the driver for making operational decisions. Much of the focus by automakers in Europe (as well as in the United States) is on developing onboard video-detection and radardetection devices. These devices detect objects such as hazards, pedestrians, or other vehicles within a prescribed range, process and interpret the nature and proximity of the object, and provide information to the driver. This information is advisory and intended to help the driver make critical decisions.
In Japan, the scan team observed presentations on efforts to link the infrastructure and vehicle. Examples include pedestrian motion detectors at crosswalks that trigger attention-getting messages to vehicles from roadside signs and work zone proximity warnings that notify drivers of changing or migrating hazard locations during the life of a project.
While video- and radar-detection systems are complex and expensive, this approach to capturing data requires less reliance on the infrastructure component for transmitting roadside information to the vehicle. The auto industry assumes that it cannot rely on public agencies to provide this critical component. While this approach could work, it shifts the responsibility to the automobile manufacturers, who depend on public acceptance and market penetration.
Collaborate and partner with the Vehicle-Infrastructure Integration (VII) Steering Committee and U.S. auto industry in designing and implementing a VII project to develop the technology for roadside features. Included would be regulatory signs, advisory signs, and traffic-control devices that could communicate information to a vehicle's onboard device. Enhanced safety for all motorists would be the primary goal.
Robert Bryant and Martin Knopp
ITS technologies increasingly have been deployed to assist in traffic operations and control. Enhanced mobility and safety have been joint products of these advances in ITS. An ever-increasing awareness in the transportation community supports the idea that mobility suffers without an emphasis on safety, resulting in both a costly breakdown of the transportation system and a negative environmental impact.
Incidents and congestion may result in secondary crashes, many of which are more serious than the original incident. Fixed or static speed limits in use since the early deployment of traffic control devices are often disregarded. Drivers traveling over the speed limit usually assume a 5- to 10-mile-per-hour (mi/h) tolerance before a law enforcement official pulls over a driver. Many courts have adopted or accepted these tolerances. The resulting speed differential between vehicles can easily reach 50 mi/h before enforcement on a roadway with a 75-mi/h speed limit unless there is active management. Drivers attempting to push the upper limits often drive aggressively to maintain their speed.
The scan team participated in a Paris, France, briefing by Paul Maarek on the A-7 Motorway variable speed control experiment. This private corporate project developed and funded by the concessionaire ASFA has listed as its dual goal the reduction of congestion and the improvement of service.
Traffic on route A-7 has been increasing by 3 percent each year. This important tollway constitutes the major route to Spain and the Riviera. Rural sections of A-7 routinely carry 75,000 average daily traffic (ADT), peaking to 117,000 ADT during the summer holiday months, making it even more difficult for ASFA to safely manage traffic.
ASFA developed algorithms that anticipate traffic conditions 30 to 45 minutes into the future. The algorithms were used to conduct an evaluation of speed on a 19-km section (one direction) of A-7 from July 31 to September 15, 2004. Using the traffic data for time of day and season, optimal speeds were determined and posted on mainline signs and at tollway entrances. Drivers not following these speed recommendations, while not officially cited, found their license tag numbers displayed on variable message signs. This pilot study is still experimental to evaluate the effectiveness of variable speed enforcement and the public's reaction.
Overhead signs and bridges have license-tag readers in place over each lane. Recommended speeds of 110 km/h had a compliance rate of 80 percent, while recommended speeds of 90 km/h had a compliance rate of 50 percent. The optimal speed was determined to be between 90 and 105 km/h. The results of this pilot are very promising, both in terms of reducing congestion but more importantly in a dynamic increase in safety. The pilot study found that congestion was reduced by 16 percent, and delay from congestion was reduced by 2 hours. The study projected an annual savings of 30,000 hours and US$1.8 million from reduced congestion, and a 48 percent reduction in crashes on the tollway. Public awareness of the speed-control messages was 87 percent, and 98 percent of drivers remember seeing at least five variable message signs. Sixty-one percent of surveyed drivers approved of the project.
Robert Bertini and Craig Allred
Safety was observed to be a core value in the daily life of citizens of the countries the scan team visited. Leaders at the highest levels of government have made a strong commitment to improving road safety and have established national goals for fatality reduction. In France, road safety was a campaign issue in past national elections. In fact, the current president has established roadway safety as a national priority. ITS has played an important role in working toward realization of the goal of improving roadway safety.
Through a top-down leadership commitment, the leaders and governments of these nations followed through with strong, automated enforcement programs showing very positive results. Both the high priority placed on road safety and the belief in safety as a core value of society were clearly evident from the behavior demonstrated by the people the scan team met. Traffic safety laws are very stringent in France, Germany, and Japan. As a result, fatality rates are lower in these countries than in the United States. This personal commitment to safety has had a dramatic impact on the design and operation of transportation facilities as well as on speed enforcement programs.
Carlos Lopez, Robert Callan, Joseph Peters, and John Njord
This scan uncovered many current and proposed applications of ITS technologies aimed at improving safety that rely on an enhanced map database resident in either the vehicle, at some centralized location, or both. In many cases these map databases would be designed to "learn" from data reported by vehicles and to provide information to other vehicles, emergency responders, incident management systems, or transportation authorities. With current navigation systems that contain static maps, the scan revealed a need to develop means of updating map data in real time, perhaps depending on the vehicle's position in real time.
The scan team also observed that some ITS safety applications require detailed speed limit boundaries. The delivery of this information sounds simple initially, but experience in both Germany and France has proven that this is quite difficult from an inventory and location basis for even a small study area. It is possible that systems could be developed using image processing to automatically update and improve speed limit boundary databases in the future, or future speed limit signs could be installed with small chips capable of communicating their location and status to a central system.
In the United States there have been, and continue to be, efforts to include map databases and to make the providers' systems interoperable in terms of location codes, accuracy, etc. All of these examples of future ITS safety applications have highlighted the importance of assessing both the level of need and the feasibility of enhancing electronic map databases used in navigation systems. A first step in this evolution would be to capture and display accurate speed limit information on the various roadway segments. This is anticipated to include acquiring the perspectives of current map data providers, as well as road-mapping specialists involved with the GIS-T software program.
Robert Bertini and Lyle Knowlton
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