System and assessment of reflective objects along a roadway

• US 8,860,944 B2
• Filed: 09/12/2013
• Issued: 10/14/2014
• Est. Priority Date: 08/12/2000
• Status: Expired due to Fees

• Current Assignee: Mandli Communications, Inc.
• Original Assignee: Facet Technology Corp.
• Inventors: Retterath, Jamie E., Laumeyer, Robert A.
• Primary Examiner(s): STAFIRA, MICHAEL PATRICK
• Application Number:
  US14/025,614
• Publication Number:
  US 20140036269A1
• Time in Patent Office: 397 Days
• US Class Current: 356/445
• CPC Class Codes: G01N 21/251 Colorimeters; Construction thereof
• CPC Class Codes: G01N 21/55 Specular reflectivity
• CPC Class Codes: G01N 21/84 Systems specially adapted for particular applications
• CPC Class Codes: G01N 2201/06113 Coherent sources; lasers
• CPC Class Codes: G01N 2201/102 Video camera
• CPC Class Codes: G01N 2201/12 Circuits of general importance; Signal processing
• CPC Class Codes: G01S 17/06 Systems determining position data of a target
• CPC Class Codes: G06V 20/56 exterior to a vehicle by using sensors mounted on the vehicle
• CPC Class Codes: G06V 20/582 of traffic signs
• CPC Class Codes: G08G 1/096758 where no selection takes place on the transmitted or the received information
• CPC Class Codes: G08G 1/096783 where the origin of the information is a roadside individual element

Abstract

A system for the assessment of reflective surfaces disposed along a roadway repeatedly illuminates an area along the roadway that includes at least one reflective surface using a 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 assessment for that reflective surface. In one embodiment, a virtual nighttime drive through along a roadway is simulated using a plurality of intensity values to simulate reflections from each reflective surface disposed along the roadway during the virtual drive through.

Claims

1. A method of assessing reflective surfaces disposed along a roadway comprising:

activating a light source as the light source is traversed along the roadway to illuminate an area that includes at least one reflective surface on a sign, the sign having a sheeting characteristic;

determining a plurality of light intensity values 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 value associated with one of the at least one reflective surface; and

analyze the portion of the at least one light intensity value to determine an assessment for the sheeting characteristic.

2. The method of claim 1, wherein the intensity sensor is a camera.

3. The method of claim 2, wherein the at least one light intensity value corresponds to the value of a pixel within a frame of an image captured by the camera of the area illuminated by the light source.

4. The method of claim 2, wherein the camera utilizes RGB color values.

5. The method of claim 2, wherein the camera is a black and white camera.

6. The method of claim 1, wherein the assessment is determined by an entry in a look-up-table.

7. A method assessing a sheeting characteristic for each of a plurality of signs disposed along a roadway, the method comprising:

activating a light source as the light source is traversed along the roadway to illuminate an area that includes at least one sign to generate at least one light intensity value, the at least one sign having a reflective surface and a sheeting characteristic;

determining a plurality of light intensity values with at least one intensity sensor without targeting a particular reflective surface; and

using a computer processing system to analyze the plurality of light intensity values associated with one of the at least one reflective surfaces to determine an assessment of the sheeting characteristic of the at least one sign.

8. The method of claim 7, wherein the intensity sensor is a camera.

9. The method of claim 8, wherein the at least one light intensity value corresponds to the value of a pixel within a frame of an image captured by the camera of the area.

10. The method of claim 8, wherein the camera utilizes RGB color value.

11. The method of claim 8, wherein the camera is a black and white camera.

12. The method of claim 7, wherein the assessment is determined by an entry in a look-up-table.

13. A system for acquiring information to assess reflective surfaces disposed along a roadway comprising:

a vehicle having;

at least one light source;

at least one light sensor; and

a control system operably connected to the light source and light sensor such that the light sensor records information associated with an area that includes at least one sign, the sign comprising a reflective surface with a sheeting characteristic, as the vehicle traverses along the roadway in response to repeated illumination of the area by the light source, wherein the information includes at least one light intensity value; and

a computer processing system that utilizes the recorded information to determine an assessment of the sheeting characteristic of the at least one sign.

14. The method of claim 13, wherein the intensity sensor is a camera.

15. The method of claim 14, wherein the at least one light intensity value corresponds to the value of a pixel within a frame of an image captured by the camera of the area.

16. The method of claim 14, wherein the camera utilizes RGB color values.

17. The method of claim 14, wherein the camera is a black and white camera.

18. The method of claim 13, wherein the assessment is determined by an entry in a look-up-table.