TRIAL IMPLEMENTATION OF A PHOTOELECTRIC SENSOR SYSTEM TO CLASSIFY VEHICLES

The development and field testing of an automatic vehicle classification (AVC) system in 1990 and 1991 are described. The system employs an inductance loop detector and a pair of photoelectric sensors emitting modulated infrared-spectrum light beams, which are reflected off raised pavement markers. The presence of a vehicle activates the loop detector, prompting the system to classify the passing vehicle. The pattern of the infrared light beam interruptions enables the system to infer the vehicle's speed, number of axles, and number of tires. The number of axles and tires defines the vehicle's class for assessing the proper toll. Signals from the activation go through a special microprocessor into a personal computer for interpretation, display, and recording. The system was tested initially at a high-speed (50 to 65 mph) Oklahoma Turnpike Authority site. Evaluation of the computer records and written field notes obtained during a 5-wk study indicated that the first-generation AVC system correctly classified about 95% of the 1,736 vehicles observed. After a review of the data and the number and type of errors found therein, it was concluded that the system software could be modified to correctly classify about 97% of the vehicles. The AVC system was subsequently modified and installed in four automatic vehicle identification toll-gate lanes on the Turner and Will Rogers turnpikes in Oklahoma, where vehicles with a special device on board are allowed to debit their toll account as they pass through without stopping. Evaluation of the AVC system operating in this environment is continuing.

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/trr/1992/1364/1364-021.pdf
• Record URL:
  https://scholar.google.com/scholar_lookup?title=TRIAL+IMPLEMENTATION+OF+A+PHOTOELECTRIC+SENSOR+SYSTEM+TO+CLASSIFY+VEHICLES&author=J.+Gattis&author=C.+Lee&publication_year=1992
• Availability:
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• Supplemental Notes:
  • This paper appears in Transportation Research Record No. 1364, Transportation Planning, Programming, Land Use, and Applications of Geographic Information Systems. 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:
  • Gattis, J L
  • Lee, Clyde E
• Publication Date: 1992

Language

• English

Media Info

• Features: Figures; Photos; References;
• Pagination: p. 179-185
• Monograph Title: Transportation planning, programming, land use, and applications of geographic information systems
• Serial:
  • Transportation Research Record
  • Issue Number: 1364
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Accuracy; Automatic vehicle identification; Infrared detectors; Loop detectors; Microprocessors; Personal computers; Software; Toll roads; Vehicle classification
• Old TRIS Terms: Photoelectric sensors
• Subject Areas: Highways; Operations and Traffic Management; Planning and Forecasting; I21: Planning of Transport Infrastructure;

Filing Info

• Accession Number: 00626935
• Record Type: Publication
• ISBN: 0309054036
• Files: TRIS, TRB
• Created Date: Feb 24 1993 12:00AM