Field evaluation of smart sensor vehicle detectors at railroad grade crossings - volume 4 : performance in adverse weather conditions.

Details

• Creators:
  Medina, Juan C. ; Benekohal, Rahim F.
• Corporate Creators:
  University of Illinois at Urbana-Champaign. Dept. of Civil and Environmental Engineering
• Corporate Contributors:
  Illinois. Dept. of Transportation. Bureau of Materials and Physical Research ; United States. Federal Highway Administration
• Subject/TRT Terms:
  Evaluation And Assessment Field Tests Microwave Detectors Radar Vehicle Detectors Railroad Grade Crossings Sensors Weather Conditions
• Publication/ Report Number:
  FHWA-ICT-15-002 ; ICT-15-002 ; UILU-ENG-2015-2002
• Resource Type:
  Tech Report
• Geographical Coverage:
  Illinois
• Corporate Publisher:
  Illinois Center for Transportation
• Abstract:
  The performance of a microwave radar system for vehicle detection at a railroad grade crossing with quadrant gates was evaluated in
  
  adverse weather conditions: rain (light and torrential), snow (light and heavy), dense fog, and wind. The first part of this report compares
  
  the results of the modified system setup in adverse weather conditions with those from good weather conditions (as presented in
  
  Volume 3 of this study). Then, the results of a re-modified system setup were compared to the results for the modified system setup in
  
  good and adverse weather conditions. The re-modification was in response to increased detection errors in adverse weather conditions.
  
  With the modified setup, system performance was sensitive to the adverse weather conditions. In torrential rain, false calls increased to
  
  24.82%–27.08% (e.g., May 28 and June 1) when there was some traffic on the crossing. However, when there was torrential rain but
  
  only one vehicle (e.g., May 31) or no traffic flow (e.g., June 10), the radar units generated 15 false calls on each of those 2 days. For all
  
  heavy snow datasets combined, missed calls by a single radar unit and by the two radar units working as a combined unit (i.e.,
  
  systemwide) represented 13.51% and 11.66% of the loop calls, respectively. The most severe snow effects were found during freezing
  
  rain/ice. In dense fog, false calls increased to 11.58%, and all false calls were generated when the gates were moving or in the down
  
  position. Wind did not affect system performance, and the errors were similar to those in good weather conditions. With the re-modified
  
  setup, the frequency of errors in heavy rain and heavy snow conditions was reduced and system performance was similar to the good
  
  weather, light rain, and light snow conditions. In heavy rain, false calls in the re-modified setup were reduced to 2.6% compared with
  
  30.5% in the modified setup. This reduction was the result of a significant decrease in the false calls generated without objects in the
  
  crossing. The re-modified setup eliminated the systemwide missed calls in heavy snow. The re-modified setup also reduced the false
  
  calls to less than 1% in good weather, light rain, and light snow conditions and practically had no missed, stuck-on, or dropped calls.
  
  Results indicate that re-modifications improved the performance of detection system.
  
  
• Format:
  PDF
• Funding:
  R27-095
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:1a31e68dc1c039345cc1426e514d66525bf6b7974c73e84f3eb0eb45078cc6db
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/28804/dot_28804_DS1.pdf
• File Type:
  [PDF - 1.04 MB ]