THE ANALYSIS AND DESIGN OF FREEWAY ENTRANCE RAMP CONTROL SYSTEMS

SOME OF THE RESULTS ARE DESCRIBED WHICH WERE OBTAINED FROM AN ANALYTIC STUDY UNDERTAKEN AS PART OF THE GULF FREEWAY SURVEILLANCE AND CONTROL PROJECT IN WHICH THE ON-LINE, DYNAMIC CONTROL OF INDIVIDUAL ENTRANCE RAMPS IS INVESTIGATED. FOR THIS STUDY 2 ALTERNATE CONTROL PHILOSOPHIES ARE CONSIDERED. THE FIRST PHILOSOPHY CONCERNS THE CONTROL OF RAMPS ON WHICH A STRING OF ONE OR MORE VEHICLES IS RELEASED WHEN A SUITABLE MERGE OPPORTUNITY ARISES AND WHEN ALL PREVIOUSLY RELEASED VEHICLES HAVE SUCCESSFULLY MERGED INTO THE FREEWAY STREAM. THE SECOND CONTROL PHILOSOPHY CONERNS RAMPS ON WHICH THE REQUIREMENT THAT THE RAMP BE CLEARED OF ALL PREVIOUSLY RELEASED VEHICLES IS RELAXED TO INCREASE THE MERGE CAPACITY OF THAT RAMP. IN THIS SECOND CASE, THE CONTROLLER MAY RELEASE AN ADDITIONAL VEHICLE WHENEVER THE EXPECTED DELAY ASSOCIATED WITH ATTEMPTING A MERGE INTO A DETECTED GAP IS LESS THAN THE EXPECTED DELAY ASSOCIATED WITH WAITING FOR THE RAMP TO SPECIAL CASES OF THE CONTROL SYSTEM ANALYSIS PRESENTED. /AUTHOR/

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/hrr/1970/303/303-005.pdf
• Supplemental Notes:
  • Paper sponsored by Committee on Freeway Operations and presented at the 49th Annual Meeting. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
• Authors:
  • Yagoda, H Nathan
  • Pignataro, Louis J
• Publication Date: 1970

Media Info

• Media Type: Print
• Features: Figures; References;
• Pagination: pp 56-73
• Monograph Title: Freeway operations, surveillance and communications
• Serial:
  • Highway Research Record
  • Issue Number: 303
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Actuated traffic signal controllers; Control; Freeway operations; Interchange ramps; Merging traffic; On ramps; Pretimed traffic signal controllers; Traffic actuated controllers; Traffic control; Traffic delays; Traffic surveillance
• Old TRIS Terms: Fixed time controller; Freeway entrances and exits; Metering; Traffic control systems
• Subject Areas: Highways; Operations and Traffic Management;

Filing Info

• Accession Number: 00225796
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Sep 21 1970 12:00AM