USA Banner

Official US Government Icon

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure Site Icon

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Public Roads - July/August 1997

Demo '97: Proving Ahs Works

pr97p30This article is adapted from information provided by the National Automated Highway System Consortium.

Highways of the future may feature relaxed drivers talking on the phone, faxing documents, or reading a novel while an automated highway system controls the vehicle's steering, braking, and throttling and allows for "hands-off, feet-off" driving. Beginning in August 1997, the National Automated Highway System Consortium (NAHSC) will illustrate that the vision of an automated highway system (AHS) that improves traffic safety and highway efficiency can be made a reality.

As required in 1997 by the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA), NAHSC will conduct a proof-of-technical-feasibility demonstration project north of San Diego to show that AHS is a viable and practical option for meeting travel demands and enhancing mobility without building new highways. The demonstration on August 7 through 10, 1997, will be a full-scale, live, multivehicle demonstration of AHS technologies that will provide stakeholders, elected officials, the media, and the general public with a glimpse of the potential safety, environmental, and efficiency benefits in a real-world, real-time setting. The demonstration also will show that the technologies needed to create an automated highway already exist or can be developed shortly.

NAHSC Core Participants
California Department of Transportation (Caltrans)
Carnegie-Mellon University
Delco Electronics
General Motors
Lockheed Martin
Parsons Brinckerhoff
University of California Partners for Advanced Transit and Highways (PATH) Program
Federal Highway Administration

NAHSC Demo Associate Participants
Eaton Vorad
Houston Metro
Thc Ohio State University/Transportation Research Center

An operational AHS will reduce congestion by using existing highways more effectively. A specially equipped AHS lane can double or triple the flow rate (in vehicles per hour) of a manual lane, even in adverse weather conditions. The increased flow rate is possible because AHS promises to: provide uniform driving performance by eliminating the accordion effect of acceleration, deceleration, and weaving typical on today's highways; eliminate traffic flow variances caused by human distractions; safely increase traffic density in the lane because of the tighter operating tolerances possible with fully automated control; and manage entries and exits so that AHS lanes maintain optimum speed and spacing in heavy traffic.

pr97p31Buick's XP2000 concept car includes a conceptual guidance system that would allow the car to travel at high speed locked on sensors buried in the road.

A 12-kilometer, high-occupancy-vehicle (HOV) segment of Interstate 15 located 16 kilometers north of downtown San Diego will be the site of the demonstration. This is a real highway - not a test track - and the demonstration "runs," using contemporary cars, buses, and light trucks, will take place between the morning and afternoon rush hours. Each day, continuous demonstrations will run for about five hours in various sequences to test the AHS system in seven areas ranging from cruise control to obstacle detection. Members of Congress, congressional staff, state and local transportation decision-makers, and private-sector executives will be invited to experience the automation technology by riding in the demonstration vehicles. Viewing stands at strategic locations will accommodate 200 spectators.

Demonstration systems will control spacing between vehicles and keep the vehicles within the lane boundaries. Almost 93,000 guidance magnets have been installed on I-15 for the demonstration. The vehicles will be equipped with sensors, computers, and communications devices to able to sense and maneuver around obstacles in time to avoid them and to communicate and exchange information with other intelligent transportation services.

Why is an automated highway system needed?

With almost 6.5 million kilometers of streets, roads, and highways and with 190 million vehicles, the United States enjoys one of the finest transportation systems in the world. However, our unparalleled mobility is threatened by rapidly increasing congestion. Concurrently, building addition infrastructure is becoming a less viable solution, due largely to environmental, community, and cost-related concerns.

Still more worrisome is the fact that our long-term trend of reducing highway fatalities has apparently ended and is now going in the wrong direction. More than 40,000 lives are lost each year on our nation's highways. The annual cost to the nation is estimated at more than $137 billion. Human error is a leading factor in 90 percent of crashes. AHS promises to boost safety by reducing and/or eliminating the element of driver error. Realizing the capacity of AHS to enhance safety can go far in saving lives, eliminating injuries, and reducing attendant human suffering and cost. This is particularly important as the related concerns of safety and congestion are expected to be exacerbated in the coming years because the total vehicle-miles traveled will nearly double by the year 2020 and our population will increase by 50 percent by the middle of the 21st century.

Information technology - "smart" highways and vehicles - offers the best solution. Automated highways will increase the safety, convenience, and overall quality of travel on U.S. highways. Anticipated results of automated highways include: significant reduction of traffic accidents, reduced traffic congestion, more predicable travel times for individuals and for the delivery of goods, better use of existing roadways, conservation of energy resources, and reduced emissions.

Although the demonstration may not directly represent the final automated highway system prototype to be completed in 2002, it will contain applications of technologies, systems, and subsystems that will be building blocks leading to a full AHS prototype. The demonstration will focus on existing technologies that can be integrated quickly to provide a solid proof of technical feasibility. Nearer term partial automation capabilities, which would facilitate a gradual implementation approach, will be a key component of the demonstration.

"Demo '97 provides a unique opportunity to witness the great variety of cutting edge technologies that are being brought to bear on the feasibility aspect of AHS. Automated lane keeping, for example, will be demonstrated in a variety of ways: one scenario follows magnets imbedded in the roadway, another tracks a radar reflective stripe, several others use a variety of vision-based systems. And the list goes on and on: laser-based systems, radar applications in obstacle detection and lateral control, advanced communications concepts, new technology advancements in infrastructure maintenance, and so forth. Our challenge is to combine all of these related efforts into a cohesive presentation for Demo '97," says Pat McKenzie of Lockheed Martin Corporation, who leads the Demonstration Systems Integration Team.

What can AHS offer in the near term?

While fully automated highway systems may be several years away, many applications are already road-ready or near ready. These include:

  • Adaptive Cruise Control that senses vehicles ahead/behind and alters speed accordingly.
  • Obstacle/Collision Avoidance that detects obstacles/other vehicles in the road and safely adjusts course.
  • Lane Keeping with sensors that track markers in/on the highway, ensuring that the lanes are followed precisely.

These technologies are already proven in concept and will be on display at Demo '97, proving their near-term utility. What's more, Demo '97 will show that these advances are adaptable to the unique transportation needs of virtually every region and community.

"Of course, the technical content has to be there, but educating our stakeholders is also a big part of the success of the demo," says Terry Quinlan, NAHSC test and demonstration manager. "Once highway users understand the true benefits of AHS, they're likely to become excited about its potential and look forward to deployment of near-term AHS technologies such as intelligent cruse control, collision warning systems, and lane departure detection."

Therefore, supporting Demo '97's exciting array of activities is a broad-based, public education program designed to activate AHS stakeholders in this effort, maximize demonstration attendance, build support for continuing the AHS Program, and promote the vision and potential benefits of AHS deployment to likely system users' operators and implementers.

Demonstration Scenarios

The NAHSC participants are working together to show the world what the future of highway travel might be. These scenarios are not a prototype for a final AHS, but they are a look at the capabilities and potential benefits of AHS to solve mounting traffic problems, such as decreasing safety and rapidly increasing congestion.

Free-Agent, Multiplatform Scenario
Carnegie-Mellon University has teamed up with the Metropolitan Transit Authority of Harris County, Texas, (Houston Metro) to show vehicle-based AHS technologies used across different vehicle platforms and to demonstrate the potential of automated vehicles operating in non-automated traffic. Using two buses, one Oldsmobile Silhouette minivan, and one Pontiac Bonneville, the scenario will showcase full automation, obstacle avoidance, and collision warning and will demonstrate an automated lane change and an operator/driver interface.

Platooning Scenario
The University of California PATH Program will present this scenario using eight specially equipped 1997 Buick LeSabres to prove the feasibility of a transportation system designed to significantly improve the throughput on U.S. highways. The vehicles were extensively modified by Delco Electronics, General Motors, Hughes, and the University of California PATH. The cars will travel in a single-file formation guided by magnets embedded in the roadway. As a group, they will accelerate, decelerate, and perform a coordinated stop (to avoid an obstacle). The platoon will split to allow other vehicles to enter and then rejoin as one platoon. Drivers will receive vital information such as vehicle speed, current maneuver, and distance to destination via a head-up display designed by Delco Electronics.

Maintenance Scenario
Caltrans will demonstrate AHS maintenance operations using the Infrastructure Diagnostic Vehicle (IDV) and the Debris Removal Vehicle (DRV). IDV, developed by Caltrans, Lockheed Martin, and the University of California at Davis, will be equipped with autonomous lateral control equipment and conventional cruise control for automated driving. IDV will also be equipped with diagnostic equipment to conduct monitoring, physical inspection, and preventative care to preserve the integrity of the AHS infrastructure. These maintenance operations will be performed while traveling under automated control at highway speeds. The DRV, developed by Pick-AII Inc., will demonstrate the automatic removal of debris from the AHS lanes.

Control Transition Scenario
In this scenario, Honda R&D will showcase two approaches to automated highway systems - an infrastructure-supported approach and an independent vehicle approach. Honda's two prototype "AHS Accords" will transition between these two approaches (infrastructure-to-vehicle communications and vehicle-to-vehicle communications) as they demonstrate platooning, automated lane changes, automated start and stop, and obstacle detection and avoidance. The use of multiple sensor systems will demonstrate the concept of back-up technology for better performance and reliability.

Alternative Technology Scenario The Ohio State University will use one manually driven car and two automated cars to show an automated vehicle pass a manually driven car in this scenario, which highlights an additional technology for lateral control. About 6.5 kilometers of the HOV lanes are equipped with radar-reflective tape produced by 3M. This tape (versus the magnets used in other scenarios) and a single camera-based vision system will be used for lateral control. An Eaton Vorad low-powered radar will be used for side vehicle detection and a laser system will be used for longitudinal control.

Evolutionary Scenario
This scenario will showcase the evolution of vehicle automation. Toyota, in conjunction with the Toyota Technical Center, IMRA, and AISIN, will use existing highway infrastructure, two concept automated vehicles - based on the Toyota Avalon - and two non-automated Toyota Camrys to consecutively demonstrate lane-departure warning, obstacle-detection warning, blind spot warning, longitudinal control using Intelligent Cruise Control, automated lateral control using vision system, obstacle avoidance using laser detection, and automated lane-change maneuvers.

ln the adjacent AHS Exposition Center at Miramar College, attendees will learn more about AHS, the consortium's work, and associated stakeholder industries and organizations through a series of exhibits, presentations, stand-alone demonstrations, component displays, and simulations designed to enlighten and entertain.

The demonstration results will help the intelligent transportation community select the most promising AHS technologies and conceptual approach, which ultimately will lead to an AHS operational test with public participation. With the summer demonstration, the NAHSC program plan will have achieved its the first major milestone and will have set the stage for an AHS prototype.

Houston Metro Seeks to Lead the Way

The Metropolitan Transit Authority of Harris County, Texas, (Houston Metro) is the only transit authority participating in Demo '97. Houston Metro is providing two New Flyer, 12.2-meter (40-foot) low-floor buses to participate in the demonstration runs. The buses will be outfitted at Carnegie-Mellon University with the hardware and software necessary to be full automated.

Houston Metro has identified automated highway technology as having potential for future application to the Houston HOV lane network as a cost-effective means of increasing vehicle throughput, and AHS will specifically be considered in Metro's long-range transportation plan. Houston Metro is seeking to be among the international leaders in the use of advanced technology to improve transportation.

"We're set to show how transit operations can be improved through AHS. It's the first major step toward adopting these new AHS technologies to help [Metro] continue to improve mobility in the Houston area, and it holds the promise to do the same for transit operations throughout the United States," said Robert MacLennan, general manager of Houston Metro.