Evaluation of LED vehicular and pedestrian modules.

Details

• Creators:
  Hajbabaie, Ali ; Benekohal, Rahim F ; Medina, Juan C. ; Chitturi, Madhav
• Corporate Creators:
  Illinois Center for Transportation
• Corporate Contributors:
  Illinois. Department of Transportation. Bureau of Materials and Physical Research
• Subject/TRT Terms:
  • Signal lights
  • Signal devices
  • Communication devices
  • Technology assessment
  • Technological innovations Traffic signs and signals
  • Electronic traffic controls
• Publication/ Report Number:
  FHWA-ICT-09-043;ICT-09-043, UILU-ENG-2009-2014
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States
• Corporate Publisher:
  Illinois Center for Transportation
• Abstract:
  This study was conducted to verify the compliance of vehicular and pedestrian LED traffic signal modules with the Institute ; of Transportation Engineers specifications; and to assess drivers’ preferences of the LED modules. Four vehicular modules ; (ACS, Dialight, Leotek, and Lumination) and three pedestrian LED modules (Dialight, Leotek, and Lumination) were used. ; The compliance verification primarily involved reviewing the independent-lab testing reports, visual inspection of the ; modules, and analyzing the manufacturers’ responses to the questionnaires prepared by the research team. The solid LED ; modules provided by ASC had several issues with compliance with the ITE specification; however, the modules from other ; companies either complied or complied with reservation with all the ITE Specifications. No general conclusion were made ; for the arrow modules since at the time of completion of this study, ITE had not adopted a final specification for them. For ; pedestrian modules, all companies submitted independent lab test reports for some of the modules, but not for all. The ; reports showed that all these modules either complied with, or complied with reservation with most of the ITE specifications. ; To assess drivers’ preferences, 120 drivers participated in the evaluation of the modules. For solid modules in daytime, the ; participants’ ratings for the ASC were significantly higher than the other three companies. In nighttime, the ASC red module ; was rated much brighter than the Leotek module. However, for solid yellow and green modules, the brightness was rated ; the same for all companies. For red arrow modules in daytime when looking straight ahead, Dialight was rated similar to ; ASC, but significantly higher than Lumination and Leotek. However, for yellow and green arrows, Dialight was rated higher ; than all other three companies were. For all three colors of the arrow modules in daytime when looking at an angle, Dialight ; and ASC were rated significantly higher than Leotek and Lumination. For the pedestrian modules in daytime, the separate ; 12” Dialight module was rated significantly higher than the Leotek and Lumination modules. For 12” combination modules, ; Leotek and Dialight were rated higher than Lumination. For the 16”*18” combination modules, Lumination was rated ; significantly higher than Dialight. In rating the traffic modules, all of the respondents chose brightness, 93% chose color, ; and 88% selected uniformity as an important factor. The most important factor was brightness for 74%, color for 26%, and ; uniformity for 27% of the participants. In rating of the pedestrian modules, all of the respondents chose brightness, 94% ; chose color, 90% selected uniformity, and 70% selected size as an important factor. The most important factor was ; brightness for 75%, color for 25%, uniformity for 25%, and size for 23% of the participants.
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• Format:
  PDF
• Funding:
  ICT-R43
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/16719/dot_16719_DS1.pdf
• File Type:
  [PDF - 1.77 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:484174fe297fbcabed971ecef9745650d94652174f2ccfa54dae3cb1c7cbe3c431e3085054b348753909dcb362d2fb3315fb06f57cd178cf38765b9145a44ce2