National Automated Highway System Research Program: A Review A Review -- Special Report 253 (1998) / Chapter Skim
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National Automated Ilig hway System Research Program A Rffiew I IDAEO TRANSPORTATION DEPARTMENT RESEARCH LIBRARY TRANSPORTATION RESEARCH BOARD NATIONAL RESEARCH COUNCIL
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TRANSPORTATION RSARCH BOARD 1998 £XE(UTIVE COMMITTEE cHAIRwoMAN: SHARON D BANKS, General Manager, AC Transit, Oakland, California VICE CHAIRMAN: WAYNE SHACKELFORD, Commissioner, Georgia Department of Transportation, Atlanta EXECUTIVE DIRECr0R: ROBERT E
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National Automated Highway SYStem Research Program A Review Committee for a Review of the National Automated Highway System Consortium Research Program TRANSPORTATION RESEARCH BOARD NATIONAL RESEARCH COUNCIL National Academy Press Washington, D.C.
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Transportation Research Board Special Report 253 Subscriber Categories IA planning and administration hA highway and facility design IVA highway operations, capacity, and traffic control IVB safety and human performance Transportation Research Board publications are available by ordering individual publications directly from the TRB Business Office, through the Internet at http://www.nas.edu/trb/index.html, or by annual subscription through organizational or individual affiliation with TRB. Affiliates and library subscribers are eligible for substantial discounts.
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Committee for a Review of the National Automated Highway System Consortium Research Program AIWEN L BEMENT, JR., Chairman, Purdue University, West Lafayette, Indiana HERBERT H
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PR[fAc[ The Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) significantly expanded the role of the U.S.
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vi PREFACE instance, believe that automated highway systems would have only marginal impact on overall highway safety, especially if these systems were deployed mainly on urban freeways and major commuter routes (which account for a relatively small share of the most serious motor vehicle crashes)
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PREFACE vii within the National Highway Traffic Safety Administration, the Federal Transit Administration, and the Federal Highway Administration. STUDY CHARGE AND ORGANIZATION OF REPORT As these changes were being debated, DOT's ITS Joint Program Office asked the National Research Council -- under the auspices of the Transportation Research Board and with assistance from the Computer Science and Telecommunications Board -- to convene a study committee to assess the appropriateness of the original vision and mission of the National Automated Highway System Research Program, the consortium's results and the effectiveness of the approach taken by NAHSC in carrying out its charge, and the role of the consortium in future research on intelligent vehicles.
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viii PREFACE ing to the questions DOT posed. At the outset of the study, the committee debated the study scope and whether it should go beyond the specific questions asked by DOT.
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PREFACE ix ACKNOWLEDGMENTS Thomas R Menzies, Jr., managed the study and drafted this report, with direction and guidance from the study committee and under the supervision of Stephen R
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CONT[NIS EXECUTIVE SUMMARY . 1 1 RESPONSES AND RECOMMENDATIONS ............3 Committee Responses .......................
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APPENDIXES A Speech by Federal Highway Administrator Rodney E Slater Announcing National Automated Highway System Consortium Research Program, October 21, 1993 .
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[xcuivt SUMARY The National Automated Highway System Research Program was begun in 1992 in response to a legislative mandate for the development of an automated highway system prototype and test track by 1997. To assist it in carrying out this mandate, the U.S.
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2 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM The task given to NAHSC of developing, evaluating, and selecting a preferred specification for a fully automated highway system in only 7 years was unlikely to be achieved because daunting technical, social, and institutional issues must be addressed and resolved. NAHSC was given dual, but conflicting, responsibilities: to promote a shared vision of automated highways and to objectively evaluate the prospects of addressing and overcoming the many complicated challenges arising in attempting to realize this vision.
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RESPONSES AND R[coM[NDArIoNs The U.S. transportation sector faces important challenges.
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4 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM The notion of fully automated driving is not new; it stems from visions of hands-off, feet-off driving that extend back more than 50 years. As demands for safety and mobility have grown and technological possibilities have multiplied, however, interest in automation has been rekindled.
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RESPONSES AND RECOMMENDATIONS ics, and communications fields -- as critical to enriching the program's expertise and resources. In the diverse and decentralized transportation sector, such cooperation and leadership also were deemed essential to garnering the extensive industry and government support and enthusiasm needed to reach early agreement on the kind of system that would influence the design, development, and deployment of automation capabilities for many decades.
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6 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM spective critique of the National Automated Highway System Research Program and NAHSC will prove valuable. Public and private partnerships will continue to command national attention, and they have vital roles in ongoing ITS development and deployment.
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RESPONSES AND RECOMMENDATIONS could happen only over time because of the technological changes that would ensue and the many societal, institutional, and economic issues that would have to be recognized, debated, and decided through public policy and political processes. The highway transportation system has become integral to the daily lives of Americans and the national economy.
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8 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM in light of not only the analytical work undertaken by the consortium but the complex challenge it encountered in trying to assess and build support for fully automated highways in the far-reaching transportation sector, the original vision of fully automated systems emerging in a preplanned, accelerated manner seems less plausible than it did 3 years ago. In the study committee's view, it would be unwise to continue efforts aimed at early specification of a preferred fully automated highway system.
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RESPONSES AND RECOMMENDA TIONS 9 riers to implementation and the safety, reliability, and cost of the technologies must be actively investigated to inform public policy. in subsequent research programs, such issues should not be neglected or repeatedly deferred because of their complexity and controversy -- nor should they be underestimated as quickly resolvable.
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10 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM In representing a new approach for conducting research and development, has NAHSC been effective and efficient? DOT's decision to establish NAHSC was bold and innovative, as was the decision of the nine public, private, and academic organizations to participate.
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RESPONSES AND RECOMMENDATIONS 11 organizational structure, its internal and external funding arrangements, and its relationship with DOT -- should be examined in light of the experiences of other collaborative efforts. Such an evaluation was not possible within the time frame and scope of this review.
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12 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM The tenor of this review should not be construed as critical of further efforts to undertake research on vehicle and highway automation with a longrange and systems perspective. Information and communications technologies undoubtedly will play an increasingly important role in meeting the nation's transportation safety and mobility needs.
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RESPONSES AND RECOMMENDA TIONS 13 and conclusions, including other findings and conclusions that can be drawn from this effort. The results should be documented and made accessible to the ITS community to help build a foundation for future work in this area.
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2 BACK6ROUND A review of the history of interest in fully automated vehicles and highways is important in helping to explain why the U.S. Department of Transportation (DOT)
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BACKGROUND 15 University -- motivated by the emerging network of modern freeways and advances in transistors and other radio and communications technologies -- investigated vehicle and roadside communications devices that would assist motorists in performing some driving tasks and provide real-time traffic and navigation information.' Fully automated highway systems were increasingly being regarded as a way to increase throughput on increasingly congested urban and intercity highways. During the late 1970s, GM received DOT funding to examine fully automated highway system concepts and identify an optimal system configuration that could be developed and deployed before the end of this century (DOT 1980; DOT 1981)
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16 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM ITS research, development, and implementation. There was a strong rationale for expanded funding.
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BACKGROUND 17 systems that take control of certain driving tasks, such as braking in an emergency or adjusting vehicle speed according to the driver's desire for distance following other vehicles ("adaptive cruise control")
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18 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM driving systems could emerge. ITS America's 1992 strategic plan, for instance, describes AVCS concepts that support automatic control as "longterm" while noting, "The goal is to have the first fully automated roadway or test track in operation by 1997" (ITS America 1992, 1-12)
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BACKGROUND 19 BOX 2-1: FHWA PLANS FOR FY 1993 HIGH-PRIORITY RESEARCH ON ADVANCED VEHICLE CONTROL SYSTEMS (FHWA 1992, 28) The following quotation from FHWA describes the agency's initial plans for an automated highway system (AHS)
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20 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM guidelines have been developed for the design of crash-warning devices and in-vehicle displays. NHTSA anticipates that the National Advanced Driving Simulator, scheduled for completion in 1999, will aid human factors research in this area (NHTSA 1997)
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BACKGROUND 21 use of automated highway technology" (DOT 1993, 4)
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22 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM A public demonstration of several automation technologies was held in San Diego, California, in August 1997, fulfilling the mandate in ISTEA. Next Steps in DOT's Program The 1997 demonstration originally was planned as the precursor to achieving the next major step in the consortium's work plan: specifying a preferred automated highway system for prototype development, testing, and demonstration.
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BACKGROUND 23 The next major milestone in the consortium's original agenda was to select a preferred automated highway system configuration, leading to the development of a final system for prototype design and testing by 2002. When presented with DOT's new plans, NAHSC sought to modify its work plan to better align it with the new emphasis.
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24 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM Shiadover, S
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NEEDS, CONCEPTS, AND ISSuES Reviewed in this chapter are the nation's major highway safety and capacity needs that underlie efforts to develop and deploy fully automated highway systems. A general description of several automation concepts, ranging from partially to fully automated systems, follows.
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26 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM the vehicle fleet rose more than 75 percent during that period (NHTSA 1996, Table 2; NHTSA 1997a, 23-28)
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NEEDS, CONCEPTS, AND ISSUES 27 example, through deflective guide rails, breakaway supports for lights and signs, crash cushions, wider medians, and tree-clear zones beside freeways. FI-IWA has fostered these improvements through its own research programs and by working with state and local authorities to encourage and mandate the use of safer roadway designs and equipment.
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28 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM simulator. It also has evaluated crash data to better understand collision problem areas and their causal factors.
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NEEDS, CONCEPTS, AND ISSUES 29 driver pooi beginning in the mid-1960s. A decade earlier, the United States had embarked on the Interstate Highway System, a public works program that has added more than 72 000 km (45,000 mi)
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30 NATIONAL AUTOMATED HIGHWAY SYSTEM REsEARCH PROGRAM enabled some jurisdictions to defer large road-building projects or avoid more stringent actions to curb driving demand. Interest in new ways to increase road capacity and influence demand for motorvehicle travel has sharpened as traffic congestion has worsened and continued to spread.
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NEEDS, CONCEPTS, AND ISSUES 31 some state and local governments are counting on ITS to improve traffic operations and overall system efficiency and capacity. Intelligent transportation systems already are being deployed and tested throughout the United States.
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32 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM Adaptive cruise control systems, which include radar braking, maybe introduced abroad within the next few years.' The following section presents an overview of several inteilgent and automated vehicle features and systems. Some are concepts; others are being developed and, in some cases, offered commercially.
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NEEDS, CONCEPTS, AND ISSUES 33 the driver when the distance equals a predefined limit for the travel speed. The system would judge the rate at which the distance in front is decreasing and give increasingly urgent warnings about the possibility of collision.
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34 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM greater than normal resistance, encouraging a reduction in vehicle speed. If a crash were imminent, the system could slow the vehicle as it approached the curve.
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NEEDS, CONCEPTS, AND ISSUES 35 fully automated driving could be achieved in alternative ways that rely to varying degrees on vehicle and infrastructure cooperation. Independent Vehicles Operating Automatically The first scenario assumes that fully automated vehicles operate along with manually driven vehicles, often traveling in the same lanes.
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36 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM operations. The roadway would have an important, possibly active, role in the control of vehicle movements and overall traffic flows.
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NEEDS, CONCEPTS, AND ISSUES 37 As Box 3-1 shows, the specification of a fully automated highway system raises complex safety, environmental, and institutional issues. These and other issues have been the subject of investigation by DOT and the NAHSC program.
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38 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM BOX 3-1 (continued) Political and Institutional Issues Many practical issues arise in considering the role of state and local governments in building and operating automated highways.
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NEEDS, CONCEPTS, AND ISSUES 39 JTS America.
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he key developments leading up to the creation of the National Automated Highway System Consortium (NAHSC) , as well as its organization and its major accomplishments since its inception in late 1994, are discussed in this chapter.
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NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM 41 tion Systems (ITS) program.
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42 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM icated lanes would serve fully automated traffic, where transition lanes would be located, whether vehicles and roadways would communicate with one another, and how much roadways would be instrumented to control vehicle speed, maneuvering, and spacing. Although the RSCs were not developed with reference to a specific application, it was generally assumed that they would permit fully automated driving on Interstate highways and other highvolume freeways.
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NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM 43 simulations, literature reviews, and multidisciplinary brainstorming sessions. The main purpose of these studies was to provide an early assessment of important issues and problems that might arise in developing and implementing fully automated highway system concepts (see Box 4-2 for examples of key findings)
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44 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM BOX 4-2 (continued) Saturation of roads near automated facilities may require geometric design and signalization changes.
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NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM 45 BOX 4-2 (continued) fail.
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46 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM In retrospect, it is now evident that too little attention was given at the analysis stage to examining the ultimate goal of the program -- to specify a preferred system in less than a decade -- as well as the way this next phase of the research program would be implemented (through a predetermined public-private consortium)
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NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM 47 Identify and describe multiple feasible system concepts, including factors that should be used to evaluate them (such factors should include institutional and legal issues assessments, technology analyses, and system costs and benefits)
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48 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM BOX 4-3: CORE MEMBERS OF NAHSC AND THEIR SPECIALTIES Bechtel Corporation -- infrastructure and environment California Department of Transportation (Caltrans) -- infrastructure development and highway operations Carnegie Mellon University -- vehicle robotics Delco Electronics -- vehicle development General Motors -- vehicle development Hughes Electronics -- communications and systems engineering Lockheed Martin -- system integration Parsons Brinckerhoff, Inc. -- traffic engineering University of California Partners for Advanced Transit in Highways (PATH/UC Berkeley)
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NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM 49 expectations, and corporate cultures. Based on guidance provided by DOT, the consortium organized its management into a three-tiered system (Figure 4-2)
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50 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM Building a consensus often involved an iterative process that required frequent meetings and communications among program managers (Bishop and Lay 1997)
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NATIONAL AUTOMA TED HIGHWAY SYSTEM RESEARCH PROGRAM 51 BOX 4-4 (continued) in markers embedded in the center of the lanes.
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52 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM accounted for approximately 15 percent of the consortium's total expenditures over the three full years of the program, it was a particularly significant expense item in view of shortfalls in federal funding. Figure 4-4 shows the original budget for federal funds, including the funding shortfalls that occurred in two of the three years following program inception.
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NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM 53 40 30 $ Million 20 10 Federal Shortfall 1995 1996 1997 1998 1999 2000 2001 2002 Fiscal Year FIGURE 4-4 NAHSC original program budget, federal share (data provided by NAHSC)
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54 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM BOX 4-5: WORKSHOPS SPONSORED BY NAHSC, 1995-1997 Opportunities for Participation Workshop, Sterling Heights, Michigan, March 1995 This public workshop sought to identify people and organizations interested in the research program and provided information about opportunities to participate. The consortium organization and process were explained.
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NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM 55 BOX 4-5 (continued) AHS and Land Use Conference, Pittsburgh, Pennsylvania, August 1996 Several commissioned papers were presented.
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56 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM vary from 2,300 to 11,000 vehicles per hour per lane (vphpl) (the highest values were for larger platoons)
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NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM 57 (HOV) lanes.
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58 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM tems "would have minimal impact on land use since it will be a relatively small part of a well-established surface transportation system" (NAHSC 1997b, 6)
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NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM 59 mated highway system. Moreover, although DOT program managers were active in the day-to-day operation of NAHSC, they may have lacked the distance needed to reflect on the consortium's early findings and experiences.
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60 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM port for the deliberate advent of a fully automated highway system. Moreover, the consortium was engrossed in planning for a demonstration of fully automated vehicle and highway technologies, as originally instructed by DOT in response to the congressional mandate.
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NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM 61 BOX 4-6 (continued) Truck Convoy with Driver in Leading Truck This possible precursor to platooning systems would involve a lead truck driver, with assistance from automation technologies, controlling the driving of several trucks in a convoy.
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62 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM BOX 4-6 (continued) Intertenninal Passenger Shuttle Several airports have driverless (rubber-tire)
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5 KfY DiscussioN POINTS AND fINDIN6S Synthesized in this chapter are the key discussion points and findings in this report, which underpin the study committee's responses to the questions in Chapter 1. These findings are organized according to the chapters from which they are drawn.
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64 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM To pursue these goals, DOT established the National Automated Highway System Consortium (NAHSC)
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KEY DISCUSSION POINTS AND FINDINGS 65 Even less certain is the overall safety effect of fully automated driving, which would depend on how and where these systems were deployed as well as assurance of their safe operation. The safety potential and reliability of fully automated systems and associated human factors issues have not received significant research attention.
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66 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM tional and decision-making processes combined to present a very difficult challenge. The effort required to undertake the congressionally mandated demonstration and shortfalls in federal funding made this challenge even more imposing.
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APPENDIX A SPEECH BY fEDERAL HIGHWAY ADMINISTRATOR RODNEY [. SLATER ANNOUNCING NATIONAL AUTOMATED HIGHWAY SYSTEM CoNSoRTIuM RESEARCH PROGRAM, OCTOBER 21, 1993 would also like to extend a warm welcome to each of you for coming to what I believe to be a historic meeting -- historic in our efforts to improve safety and mobility of the vehicle highway system and another step forward to this new era for the system.
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68 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM Our current highway transportation system, as effective and as elegant as it is, is at a critical crossroads in its evolution and has started to plateau in its ability to provide significant new operating performance in its present form. The deployment of IVHS technologies will offer substantial performance improvements in this and in coming decades.
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SPEECH By RODNEY F SLA TER 69 First, our highest priority is to get our economy moving and to create jobs through strategic transportation investment.
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70 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM national consensus-building, we can, we will -- we will -- develop an Automated Highway System which will revolutionize our approach to safety and mobility. We encourage your participation in this great endeavor, knowing that your creating energies and determined efforts will assure that the United States transportation system -- both the roads and the vehicles which operate on them -- will be safer, more effective, and responsive to the challenges of the 21st century.
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APPENDIX B PR[S[NnRS AND PARTICIPANTS During the course of the study, the following individuals participated in meetings or made presentations to the study committee: David Barry, Director, IVHS and Research Programs, National Private Truck Council Richard Bishop, former Program Manager, Automated Highway System Research, Federal Highway Administration Stephen Carlton, Acting Program Manager, National Automated Highway System Consortium Henry E Dittmar, Executive Director, Surface Transportation Policy Project Anthony Hitchcock, Consultant Ralph Hitchcock, Honda Motor Company of North America Christine M
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STUDY CoMMITTEE BIOGRAPHICAL INfORMATION ARDEN L BEMENT, JR., Chairman, is Basil S
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STUDY COMMITTEE BIOGRAPHICAL INFORMATION 73 tions, and Acting General Manager.
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74 NATIONAL AUTOMATED HIGHWAY SYSTEM RESEARCH PROGRAM NANCY G LEVESON is Hunsaker Visiting Professor of Aeronautical Information Engineering at the Massachusetts Institute of Technology and Boeing Professor of Computer Science at the University of Washington.
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STUDY COMMITTEE BIOGRAPHICAL INFORMATION 75 Fellow of the Society of Automotive Engineers and the Institute of Electrical and Electronic Engineers.
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The Transportation Research Board is a unit of the National Research Council, which serves the National Academy of Sciences and the National Academy of Engineering. The Board's mission is to promote innovation and progress in transportation by stimulating and conducting research, facilitating the dissemination of information, and encouraging the implementation of research results.
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