A methodology has been developed to isolate all the independent variables affecting night driving visibility such as sources, reflective surfaces, transmission media and observer. It is shown that correlation was achieved between the results obtained from field experiments for the unopposed roadway obstacle detection task and corresponding calculations based on accurate field illumination engineering data and observer laboratory visual performance data. Using the luminance difference method developed during the visual performance studies, the report demonstrates how the illuminance characteristics of the source interacting with the scene luminance factors can affect the luminance difference signal available for detection with respect to the luminance difference signal required by the observer. Examples of the application of this type of approach are also given to analyze the unopposed case and the interaction with other sources of illuminance such as moonlight, dusk skylight and opposing headlights. By means of these examples the sensitivity of visibility to the field, source and task parameters is also shown. Extension of the methodology to statistical population performance evaluations is outlined and current research in progress for obtaining a statistical measure of the parameters affecting headlamp population behavior is briefly outlined. /Author/SRIS/

  • Supplemental Notes:
    • An expanded version of a paper presented at the International Automotive Engineering Congress and Exposition, Detroit, Michigan, February 28-March 4, 1977.
  • Corporate Authors:

    National Aeronautical Establishment, Canada

    Montreal Road
    Ottawagton, ONo K1A ORG,   Canada 
  • Authors:
    • Pinkney, H F
    • Ayad, A A
    • HUCULAK, P
    • Harrison, A L
  • Publication Date: 1977-8

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 69 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00172475
  • Record Type: Publication
  • Source Agency: National Safety Council Safety Research Info Serv
  • Report/Paper Numbers: NRC 16322,MS-140
  • Files: TRIS
  • Created Date: Jun 14 1978 12:00AM