SCHEDULING OF TRAFFIC LIGHTS - A NEW APPROACH

THE DETERMINATION OF TRAFFIC LIGHT PHASES AND PHASE SEQUENCES AS PART OF THE SCHEDULING PROBLEM IS CONSIDERED. ALL POSSIBLE PHASES ARE SYSTEMATICALLY DETERMINED FROM THE PAIRWISE INCOMPATIBILITIES (INTOLERABLE CONFLICTS) OF TRAFFIC STREAMS IN THE INTERSECTION. FOR THE PHASE SEQUENCES IT IS ASSUMED THAT EACH LIGHT MAY BE GREEN IN AN ARBITRARY NUMBER OF SUCCESSIVE PHASES. HOWEVER, IT IS STIPULATED THAT THERE MUST BE EXACTLY ONE GREEN INTERVAL PER CYCLE FOR EACH LIGHT. FOR GIVEN-PHASE SEQUENCES OPTIMIZATION OF A SCHEDULE WITH RESPECT TO AN ARBITRARY NUMBER OF COORDINATION REQUIREMENTS IS CONSIDERED. THE DETERMINATION OF PHASE DURATIONS AND OFFSET IS FORMULATED AS A LINEAR PROGRAM WITH A SPECIAL STRUCTURE. THE FEASIBILITY OF THIS PROGRAM DEPENDS ON THE CYCLE TIME, THE REQUIRED MINIMAL GREEN TIMES AND THE PAIRWISE INCOMPATIBILITIES. A SIMPLE FEASIBILITY TEST IN TERMS OF "BLOCKING GROUPS" IS GIVEN, AND A CONSTRUCTION FOR AN INITIAL BASIC SOLUTION IS DERIVED FROM IT. A SPECIAL ALGORITHM FOR THE OPTIMIZATION IS PRESENTED. THE PERIODIC REPETITION OF THE SCHEDULE AT THE INTERSECTION IS ACCOUNTED FOR IN THE ALGORITHM. /RRL/A/

• Supplemental Notes:
  • Vol 2, No3, PP 199-234, 27 FIG, 23 REF
• Authors:
  • Stoffers, K E
• Publication Date: 1967

Media Info

• Serial:
  • Transportation Research /UK/
  • Volume: 2
  • Issue Number: 3
  • Publisher: Pergamon Press, Incorporated

Subject/Index Terms

• TRT Terms: Algorithms; Green interval (Traffic signal cycle); Intersections; Scheduling; Traffic flow; Traffic signal control systems; Traffic signal cycle; Traffic signal timing; Traffic signals
• Old TRIS Terms: Phase
• Subject Areas: Highways; Operations and Traffic Management;

Filing Info

• Accession Number: 00227152
• Record Type: Publication
• Source Agency: Road Research Laboratory /UK
• Files: TRIS
• Created Date: Apr 27 1970 12:00AM