This report is concerned with the description and analysis of a series of unopposed automobile headlighting experiments. The study emphasizes the phenomena involved in the detection of dark obstacle targets simulating the hazardous objects encountered during night driving. In the detection experiment, the visibility levels are established for the observer-driver by retracting the visual targets at predetermined distances from the test vehicle. This luminance difference signal at or near the threshold of detection defines the visual task. Laboratory work measured observer visual potential in luminance difference discrimination in order to supplement the field studies. The influences of atmospheric luminance, dynamic vehicle pitch, target shadow enhancement, foreground luminance and fixation duration are included in the analysis of the field detection trials. Several different measures of target visibility are employed. It is shown that a centroidal value of target luminance difference can be used as an index of the detection of dark hazard-like objects of concern in night driving. One-to-one correspondence was established between laboratory measurements of visual potential and roadway detection trials showing that a comprehensive treatment of the detection processes associated with night driving is possible. /Author/

  • Corporate Authors:

    National Aeronautical Establishment, Canada

    Montreal Road
    Ottawagton, ONo K1A ORG,   Canada 
  • Authors:
    • HUCULAK, P
  • Publication Date: 1978-5

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 44 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00184571
  • Record Type: Publication
  • Source Agency: National Safety Council Safety Research Info Serv
  • Report/Paper Numbers: MS-141; NRC 16780
  • Files: ITRD, TRIS
  • Created Date: Feb 3 1979 12:00AM