ROLE OF COMPUTERS IN WIDE-ARE CONTROL OF ROAD TRAFFIC, PART 1

The author describes the various forms of traffic control to date (except computer control) in the first of a four-part series on the application of computers to traffic control. Automatically-operated signals replaced manual ones in 1926, and vehicle-actuated signals were introduced in 1932. A contact-strip vehicle detector under 1 rubber pad was set into the road surface. Groups of controlled intersections are often linked by fixed-time sequences. A 'master' controller allows for discrepancies in traffic-flow volumes. Fixed-time cycles are suitable for heavy traffic flows. Pneumatic detectors replaced contact-strip detectors, and electronic timing circuits superseded neon-type timing circuits. Fixed time and vehicle-actuated modes of traffic control do not respond quickly enough to the multitude of traffic situations experienced within cities. When two or more linked controls require to use the same controller at the same instant, indecisions are created in the controller. See also IRRD abstracts nos. 211596-211598. /TRRL/

• Supplemental Notes:
  • See also HRIS 096739, 096740 and 096741.
• Corporate Authors:

  IPC Building and Control Journals, Limited

  Dorset House, Stanford Street
  London SE1 9LU,   England 
• Authors:
  • Honey, D W
• Publication Date: 1974-8-16

Language

• English

Media Info

• Pagination: p. 10-11
• Serial:
  • Surveyor - Public Authority Technology
  • Volume: 144
  • Issue Number: 4288
  • Publisher: IPC Building and Contract Journals Limited

Subject/Index Terms

• TRT Terms: Actuated traffic signal controllers; Area traffic signal control; Automatic control; Automation; Digital computers; Equipment; Highway traffic control; Intersections; Pretimed traffic signal controllers; Sensors; State of the art studies; Traffic actuated controllers; Traffic control devices; Traffic signals; Video imaging detectors
• Old TRIS Terms: Wide area traffic control
• ITRD Terms: 669: Area traffic control; 3882: Automatic; 8673: Digital computer; 3674: Equipment; 455: Junction; 6120: Sensor; 565: Traffic signal; 557: Vehicle actuated
• Subject Areas: Highways; Operations and Traffic Management; I73: Traffic Control;

Filing Info

• Accession Number: 00096738
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Files: ITRD, TRIS
• Created Date: Sep 30 1975 12:00AM