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Enhanced Rear Lighting and Signaling Systems

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Enhanced Rear Lighting and Signaling Systems DOT HS 809 425 March 2002 Enhanced Rear Lighting and Signaling Systems: Literature Review and Analyses of Alternative System Concepts This publication is distributed by the U.S. Department of Transportation, National Highway Traffic Safety Administration, in the interest of information exchange. The opinions, findings and conclusions expressed in this publication are those of the author(s) and not necessarily those of the Department of Transportation or the National Highway Traffic Safety Administration. The United States Government assumes no liability for its content or use thereof. If trade or manufacturers names or products are mentioned, it is because they are considered essential to the object of the publication and should not be construed as an endorsement. The United States Government does not endorse products or manufacturers. Technical Report Documentation Page 1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. DOT HS 809 425 4. Title and Subtitle 5. Report Date Enhanced Rear Lighting And Signaling Systems: March, 2002 Literature Review and Analyses of Alternative System Concepts 6. Performing Organization Code `7. Author(s) 8. Performing Organization Report No. Suzanne E. Lee, Walter W. Wierwille, and Sheila G. Klauer 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) Virginia Tech Transportation Institute 3500 Transportation Research Plaza (0536) 11. Contract or Grant No. Blacksburg, VA 24061 DTNH 22-99-C-07235 12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered National Highway Traffic Safety Administration NHTSA, NRD-13 Task 1 Final Report 400 7th St SW Washington, DC 20590 14. Sponsoring Agency Code 15. Supplementary Notes Michael Perel was the NHTSA COTR for this project. 16. Abstract Rear-end crashes are the most frequently occurring type of collision, accounting for approximately 29% of all crashes and resulting in a substantial number of injuries and fatalities each year. Rear-end collisions in which the lead vehicle is stopped or moving very slowly prior to the crash account for the majority of these accidents. Over the years several initiatives have addressed the problem of rear-end crashes, with limited success. The most public of these ventures was the center high-mounted stop lamp (CHMSL), which was required to be present on automobiles beginning with model year 1986. The long-term effectiveness of the CHMSL has leveled off at about a 4% effectiveness in preventing rear-end crashes, which means there is still much room for improvement. The goal of this research effort is to develop and test a small number of enhanced rear-lighting concepts that have the potential to reduce the number of rear-end collisions. These are to include problems with stopped vehicles. This report encompasses the first task of the research effort. Task 1 involved investigating all previous efforts to develop enhanced rear-lighting systems, determining the causes of rear-end crashes, and developing a short list of rear-lighting alternatives to be tested in future research efforts under this project. The literature review revealed that numerous rear-lighting systems have been proposed over the past 30 years. Focus groups conducted with law enforcement officers found that the most common cause of rear-end crashes is driver inattention and distraction, with following too closely as the next most common cause. A review of several crash database analyses revealed similar results, as did a study in which drivers of striking vehicles were interviewed. The final subtask was to conduct a trade study to suggest two to three rear-lighting concepts for further study. An expert panel consisting of twelve rear-lighting experts was assembled. The trade study was conducted electronically (email) via a series of three questionnaires. This process resulted in the recommendation of three rear-lighting configurations for further refinement. Algorithms for the activation and deactivation of these systems were also developed during Task 1. 17. Key Words 18. Distribution Statement rear lighting, brake lights, rear-end crashes, rear signaling, focus groups, subject matter experts, trade study 19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price Unclassified Unclassified 139 Form DOT F 1700.7 (8-72) Reproduction of completed page authorized i ii TABLE OF CONTENTS LIST OF TABLES......................................................................................................................................................V LIST OF FIGURES.................................................................................................................................................VII EXECUTIVE SUMMARY ................................................................................................................................... VIII ACKNOWLEDGEMENTS ..................................................................................................................................... XI LIST OF ABBREVIATIONS…………………………………………………………………………….…….…XII INTRODUCTION .......................................................................................................................................................1 LITERATURE REVIEW ...........................................................................................................................................5 GOALS OF THE LITERATURE REVIEW.........................................................................................................................5 DATABASE AND STATISTICAL ASSESSMENT ..............................................................................................................6 Problem Size of Rear-End Collisions...................................................................................................................6 Statistics Analyzed by Age and Gender................................................................................................................9 Common Scenarios for Rear-End Collisions .......................................................................................................9 Possible Contributing Factors for Rear-End Collisions....................................................................................12 Avoidance Maneuvers ........................................................................................................................................16 Vehicle Types .....................................................................................................................................................16 DEVELOPMENT AND EVALUATION OF REAR-SIGNALING SYSTEMS .........................................................................16 Standardization/Regulations of Rear-Signaling Systems ...................................................................................17 Development and Evaluation of Rear-Signaling Systems ..................................................................................17 Rear-signaling Efforts for Commercial Trucks and Transit Buses ....................................................................24 Design Guidelines..............................................................................................................................................24 Long-term Effectiveness of the Center High-Mounted Stop Lamp.....................................................................27 NHTSA Statement of Policy for New Signaling Ideas........................................................................................28 REAR-LIGHTING CONFIGURATIONS AND CHARACTERISTICS....................................................................................30 Rear-Lighting Configurations............................................................................................................................30 Lighting Characteristics.....................................................................................................................................33 Driver Characteristics .......................................................................................................................................37 Visual Factors in Warning Lights ......................................................................................................................39 PATENTS AND UNPUBLISHED LITERATURE ORGANIZED BY TYPE OF INFORMATION PRESENTED ............................40 Information Presented: Brakes Have Been Applied...........................................................................................40 Information Presented: Deceleration.................................................................................................................45 Information Presented: Stopped Vehicle............................................................................................................50 Information Presented: Safe Following Distance.............................................................................................51 Information Presented: Release of Accelerator .................................................................................................51 Information Presented: Blind Spot Identification .............................................................................................53 System Type: Closed-loop Systems ...................................................................................................................53 System Type: Programmable Turn Signal.........................................................................................................54
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