A METHOD OF COLLECTING DATA ON SPEEDS AND HEADWAYS ON A MOTORWAY

The collection and analysis process is described for A method of determining speeds and headways on the overhead section of the M4 in west London. Time lapse photography was used for data collection. The types of photographic and film analysis equipment used are specified. In the film analysis mode each photographic frame is projected down onto a screen and any point on that frame can be located by a cursor. The x and y coordinates of that point are given by visual displays and either or both can be punched onto paper tape. The speed of a vehicle is found by measuring the coordinates of its front and rear relative to a reference line and by knowing the distance the vehicle moves between frames. An example is given of typical output from the film analyser. It is concluded that despite the expense of the equipment and the slowness, this method of time lapse photography can be successfully applied in analyses of traffic passing A point on the road. /TRRL/

  • Availability:
  • Corporate Authors:

    Printerhall Limited

    29 Newmart Street
    London W1P 3PE,   England 
  • Authors:
    • Branston, D M
  • Publication Date: 1975-10

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00133691
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS
  • Created Date: Jun 23 1976 12:00AM