The development of signal technology is outlined. From the 1920s with the initial concepts of isolated junction control, detection by pneumatic strips, and certain cabled linking schemes in Glasgow and London, there was little real development in control systems until the advent of computer technology in the 1960s and microprocessors in the 1970S. Computers permitted the concepts of area traffic control, facilitating the calculation of signal timings and offsets for differing traffic conditions, and monitoring and controlling the performance of the signals centrally. Microprocessors now permit a wider range of functions to be carried out, both in relation to isolated signal operation and to system development. The concept of intelligence as applied to hardware has also led to new approaches in system design, to simplified man/machine interface, and to improved reliability. The paper examines the history of signal development and takes a number of specific examples of hardware and control techniques in order to illustrate the recent developments and facilities now available to the practising engineer. This paper was presented at the National Conference of the Institution of Highways and Transportation on "Transportation in Conurbations" held in London on 1st and 2nd December 1983. (TRRL)

  • Availability:
  • Corporate Authors:


    LONDON,   United Kingdom  WC1H 0DZ
  • Authors:
    • Mowatt, A
  • Publication Date: 1984-4

Media Info

  • Features: Figures; Photos; References;
  • Pagination: 8 p.
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00387603
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, TRIS
  • Created Date: Aug 30 1984 12:00AM