System for automated determination of retroreflectivity of road signs and other reflective objects
AssigneeFacet Technology Corp.
InventorsJames E. Retterath, Robert A. Laumeyer
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Abstract
A system for the automated determination of retroreflectivity values for reflective surfaces disposed along a roadway repeatedly illuminates an area along the roadway that includes at least one reflective surface using a strobing light source. Multiple light intensity values are measured over a field of view which includes at least a portion of the area illuminated by the light source. A computer processing system is used to identifying a portion of the light intensity values associated with a reflective surface and analyze the portion of the light intensity values to determine at least one retroreflectivity value for that reflective surface.
Claims1
A method of automated determination of retroreflectivity values for reflective surfaces comprising:
- strobing a light source to illuminate an area that includes at least one reflective surface without targeting the light source on a particular reflective surface;
- collecting a plurality of light intensity measurements with at least one intensity sensor directed to cover a field of view which includes at least a portion of the area illuminated by the light source;
- and
- using a computer processing system to:
- identify a portion of at least one light intensity measurement associated with one of the at least one reflective surfaces;
- and
- analyze the portion of the at least one light intensity measurement to determine at least one retroreflectivity value for that reflective surface.
Dependencies are inferred from the claim text.