VISUAL REQUIREMENTS IN NIGHT DRIVING

FOUR STUDIES WERE MADE TO ASSESS THE KIND AND INTENSITY OF VISUAL DATA PRESENTED TO THE DRIVER DURING NIGHTTIME DRIVING. A STUDY OF HIGHWAY LUMINANCE AND VEHICLE CONTROL SHOWED THAT A DRIVER CAN PERFORM REMARKABLY WELL WITH ONLY ONE PERCENT OF NORMAL NIGHTTIME LUMINANCE. IN THE SECOND STUDY, VISIBILITY WAS MORE SEVERELY DEGRADED, THE DRIVER BEING ALLOWED ONLY A SMALL AREA OF THE ROAD BY WHICH TO DRIVE. VELOCITY SELECTION WAS FOUND TO BE A FUNCTION OF DISTANCE TO AVAILABLE IMFORMATION AND VELOCITY MAINTENANCE OF THE ANGLE OF INFORMATION. LAMPS LOCATED ABOUT 75 FEET AWAY PRODUCED THE LOWEST VARIABILITY IN VELOCITY AND STEERING-WHEEL MOVEMENTS AND THE HIGHEST AVERAGE VELOCITY. WHEREAS LANE MARKERS WERE USED FOR TRACKING BECAUSE OF THEIR HIGH CONTRAST, THERE WAS NO TENDENCY TOWARD TRACKING ON UNLINED ROADS REGARDLESS OF LAMP PLACEMENT. THE THIRD STUDY WAS LARGELY THE SAME AS THE SECOND BUT PARTITIONED THE FIELD OF VISION. AGAIN, SUBJECTS PREFERRED INFORMATION 75--100 FEET AWAY FOR VELOCITY SELECTION, AND DRIVER ALLOWANCE FOR TIME WAS NEARLY LINEAR WITH RESPECT TO PREVIEW DISTANCE AND VELOCITY. THE FINAL STUDY WAS DIRECTED TOWARD EYE MOVEMENTS IN DAYTIME AND NIGHTTIME DRIVING. DRIVERS TENDED TO DRIVE AT NIGHT WITH THEIR FOCUS CLOSER IN FRONT OF THE VEHICLE THAN IN DAYTIME.

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  • Supplemental Notes:
    • Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved. 38 PP, 36 FIG, 13 TAB, 20 REF, 1 APP
  • Authors:
    • Rockwell, T H
    • Ernst, R L
    • Rulon, M J
  • Publication Date: 1970

Media Info

  • Media Type: Digital/other
  • Serial:
    • NCHRP Report
    • Issue Number: 99
    • Publisher: Transportation Research Board
    • ISSN: 0077-5614
  • Publication flags:

    Open Access (libre)

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Filing Info

  • Accession Number: 00221133
  • Record Type: Publication
  • Files: TRIS, ATRI
  • Created Date: Dec 28 1970 12:00AM