INFRARED DEVICE DETECTS FOG

INFRARED TECHNOLOGY COMBINED WITH AN ELECTRONIC SENSING AND AND CONTROL SYSTEM GIVES MOTORISTS ADVANCE WARNING WHEN FOG CONDITIONS EXIST ON A STRETCH OF INTERSTATE 80 S AT FORT MORGAN, COLORADO. THE WARNING SYSTEM CONSISTS OF A NETWORK OF SIX SENSORS SPACED ALONG A HALF-MILE SECTION OF THE HIGHWAY. LOCATED TEN FEET ABOVE GROUND LEVEL, THE SENSORS EMPLOY MEASUREMENT OF BACKSCATTER AND ATMOSPHERIC ATTENUATION TO SENSE THE REDUCED VISIBILITY CONDITION. AS VISIBILITY IS REDUCED TO LESS THAN 1,000 FEET AT ONE OR MORE OF THE SENSORS, FLASHING WARNING SIGNS ARE ACTIVATED ON EITHER SIDE OF THE AFFECTED AREA. THE SENSOR UNITS EMPLOY TRANSISTOR AND INTEGRATED CIRCUITRY TO MEASURE THE BACKSCATTER AND ADSORPTION OF NEAR INFRARED LIGHT ENERGY. INFRARED EMITTING DIODES ARE USED AS THE MODULATING SOURCE FOR BOTH MEASUREMENTS. SENSOR UNITS ARE MAINTAINED AT A CONSTANT TEMPERATURE TO MINIMIZE EFFECTS OF ICE AND SNOW ON THEIR OPERATION.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/1606878
• Supplemental Notes:
  • 7304
• Publication Date: 0

Media Info

• Pagination: p. 58
• Serial:
  • Public Works
  • Volume: 104
  • Issue Number: 4
  • Publisher: Hanley Wood
  • ISSN: 0033-3840
  • Serial URL: http://www.pwmag.com

Subject/Index Terms

• TRT Terms: Electronic equipment; Fog; Infrared detectors; Traffic signs; Visibility; Warning systems
• Old TRIS Terms: Electronic devices; Flashing sign
• Subject Areas: Highways; Safety and Human Factors;

Filing Info

• Accession Number: 00222311
• Record Type: Publication
• Files: TRIS
• Created Date: Apr 27 1974 12:00AM