Evaluation of Sensys Wireless Detection System: Year-After Evaluation and Off-Center Sensors

This is the third and final report of the evaluation of the Sensys wireless vehicle detection system at a signalized intersection and a railroad grade crossing. It presents the system performance after one year of its initial installation, and when additional off-center sensors were installed at the stop bar zones of the signalized intersection. Results from the signalized intersection showed no significant changes one year after the system was in use, except for a decrease in the frequency of false calls due to vehicles in adjacent lanes (from a range of 5.6%-7.6%, to a range of 0.8%-2.4%). At the stop bar zones, multiple calls generated by a single vehicle remained similar (between 7% and 10.2%), and no missed, stuck-on, or dropped calls were found. Also, the detection performance at the advance zones did not change. Missed vehicles ranged between 0.6% and 6.1%, most of which were traveling between lanes, and false calls were lower than 2%. At the railroad grade crossing, the performance of the Sensys system after one year did not show significant changes. Stuck-on calls due to trains were rare and occurred at a rate of about one occurrence for every 150 trains. False calls in the left-turn lane due to vehicles in the opposite direction remained high (more than 30%, caused by trucks and smaller vehicles), and missed calls were lower than 1%. The installation of sensors off-center relative to the loop detectors at the stop bar zones of the signalized intersection (close to the leading edge of the loops), resulted in lower number of multiple calls from a single vehicle (from 7%-10.2% down to 2%-3.3%). However, it did not improve on the frequency of false calls due to vehicles in the adjacent lanes.

• Record URL:
  • https://www.ideals.illinois.edu/bitstream/handle/2142/45834/FHWA-ICT-11-083.pdf?sequence=2
• 
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/01979191
• Corporate Authors:

  University of Illinois, Urbana-Champaign

  Department of Civil and Environmental Engineering
  205 North Mathews Avenue
  Urbana, IL  United States  61801-2352

  University of Illinois, Urbana-Champaign

  Illinois Center for Transportation, 1611 Titan Drive
  Rantoul, IL  United States  61866

  Illinois Department of Transportation

  Bureau of Materials and Physical Research
  126 East Ash Street
  Springfield, IL  United States  62704-4766

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Medina, Juan
  • Benekohal, Rahim
  • Hajbabaie, Ali
• Publication Date: 2011-6

Language

• English

Media Info

• Media Type: Web
• Edition: Research Report
• Features: Figures; Tables;
• Pagination: 24p
• Serial:
  • Civil Engineering Studies, Illinois Center for Transportation Series
  • Issue Number: 11-083
  • Publisher: University of Illinois, Urbana-Champaign
  • ISSN: 0197-9191

Subject/Index Terms

• TRT Terms: Detectors; Loop detectors; Magnetometer detectors; Railroad grade crossings; Sensors; Signalized intersections; Wireless communication systems
• Subject Areas: Highways; Operations and Traffic Management; Railroads; I73: Traffic Control;

Filing Info

• Accession Number: 01354156
• Record Type: Publication
• Report/Paper Numbers: FHWA-ICT-11-083, ICT-11-083, UILU-ENG-2011-2009
• Contract Numbers: ICT R27-58
• Files: TRIS, USDOT, STATEDOT
• Created Date: Oct 19 2011 12:53PM