A MINI-COMPUTER TRAFFIC SIGNAL CONTROLLER

IN MARCH 1971 THE CALIFORNIA DIVISION OF HIGHWAYS PUT INTO OPERATION ON U.S. 50 NEAR SACRAMENTO A SIGNALIZED INTERSECTION CONTROLLED BY A PROGRAMMABLE, GENERAL-PURPOSE MINICOMPUTER THAT HAS THE FLEXIBILITY OF ADDING PHASES OR EXTRA LOGIC FEATURES TO AN INTERSECTION WITH ONLY MINOR PROGRAM CHANGES AND/OR ADDITIONAL PLUG-IN MEMORY. THE INTERSECTION OPERATION IS FULL TRAFFIC-ACTUATED, WITH FIVE VEHICLE AND THREE PEDESTRIAN PHASES. TRAIN MOVEMENTS ON ADJACENT RAILROAD TRACKS CAUSE PREEMPTION OF THE SIGNAL SEQUENCING. THE DIVISION IS NOW PREPARING PLANS FOR A PROTOTYPE CABINET THAT WILL ENCOMPASS ALL FEATURES FOR AN EIGHT-PHASE SIGNAL WITH PEDESTRIAN PHASES, RAILROAD PREEMPTION, AND FIRE EQUIPMENT PREEMPTION.

• Supplemental Notes:
  • Vol 50, No 4, P 8, 1 PHOT
• Authors:
  • Estep, A C
• Publication Date: 1971-10

Media Info

• Serial:
  • American Highways
  • Publisher: American Highway Users Alliance

Subject/Index Terms

• TRT Terms: Information processing; Intersections; Minicomputers; Signalized intersections; Traffic actuated controllers; Traffic signals
• Subject Areas: Highways; Operations and Traffic Management;

Filing Info

• Accession Number: 00226153
• Record Type: Publication
• Files: TRIS
• Created Date: Apr 2 1972 12:00AM