METHODS, APPARATUS AND SYSTEMS FOR SURFACE TYPE DETECTION IN CONNECTION WITH LOCATE AND MARKING OPERATIONS

• US 20120065924A1
• Filed: 08/15/2011
• Published: 03/15/2012
• Est. Priority Date: 08/13/2010
• Status: Active Grant

• Current Assignee: Certusview Technologies LLC (Dycom Industries Incorporated)
• Original Assignee: Certusview Technologies LLC (Dycom Industries Incorporated)
• Inventors: Nielsen, Steven, Chambers, Curtis, Farr, Jeffrey, Vice, Jack M.
• Granted Patent: US 9,046,413 B2
• Time in Patent Office: Days
• US Class Current: 702/135
• CPC Class Codes: G01C 15/02 Means for marking measuring points
• CPC Class Codes: G01J 3/0264 Electrical interface; User interface
• CPC Class Codes: G01J 3/463 Colour matching
• CPC Class Codes: G06V 20/13 Satellite images

Abstract

Systems, methods, and apparatus for performing surface type detection in connection with locate and marking operations. In some embodiments, one or more sensors (e.g., radiation sensors, acoustic sensors, color sensors, light sensors, etc.) may be employed to collect information regarding a surface, such as a ground surface on which marking material is to be dispensed to mark the presence or absence of an underground facility. The collected sensor data may be analyzed to provide an estimate of a type of the surface that is being sensed. For example, a still-image or video camera may be used as a sensor that detects visible light reflecting from a surface. One or more images of the surface captured by the camera may be analyzed using some suitable image analysis software to identify one or more characteristics (e.g., color, intensity, randomness, presence/absence of lines, etc.) that may be indicative of a surface type. As another example, one or more radiation sensors may be employed to measure an amount of electromagnetic radiation reflected by the sensed surface one or more selected wavelengths or ranges of wavelengths to identify a spectral signature that may also be indicative of a surface type.

Claims

1. An apparatus for determining a surface type of a surface on which marking material is to be dispensed by a marking device to mark a presence or an absence of at least one underground facility within a dig area, wherein at least a portion of the dig area is planned to be excavated or disturbed during excavation activities, the apparatus comprising:

at least one communication interface;

at least one memory to store processor-executable instructions; and

at least one processor communicatively coupled to the at least one memory and the at least one communication interface, wherein, upon execution of the processor-executable instructions, the at least one processor;

A) obtains sensor data relating to the surface to be marked, the sensor data being collected by one or more sensors attached to the marking device;

B) retrieves reference data associated with a plurality of surface types; and

C) generates surface type information based at least in part on the sensor data and the reference data.

2. The apparatus of claim 1, wherein in C), the at least one processor:

C1) identifies, based at least in part on the sensor data and the reference data, at least one of the plurality of surface types as a candidate surface type for the surface to be marked.

3. The apparatus of claim 2, wherein the reference data comprises a plurality of reference signatures, each reference signature being associated with at least one corresponding surface type of the plurality of surface types, and wherein in C1), the at least one processor:

C2) determines, based at least in part on the sensor data, a surface signature associated with the surface to be marked; and

C3) identifies at least one reference signature as being a closest match with the surface signature, wherein the at least one surface type corresponding to the at least one reference signature is identified as the candidate surface type in C1).

4. The apparatus of claim 1, wherein in C), the at least one processor:

C1) identifies, based at least in part on the sensor data and the reference data, each of the plurality of surface types as being unlikely to match the surface to be marked.

5. The apparatus of claim 1, wherein the reference data comprises a plurality of reference signatures, each reference signature being associated with at least one corresponding surface type of the plurality of surface types, and wherein in C), the at least one processor:

C1) determines, based at least in part on the sensor data, at least one surface signature associated with the surface to be marked; and

C2) associates at least one confidence score with each one of the plurality of surface types, based at least in part on an extent to which the at least one surface signature matches at least one reference signature associated with the one of the plurality of surface types.

6. The apparatus of claim 5, wherein in C), the at least one processor:

C3) identifies at least one of the plurality of surface types as being unlikely to match the surface to be marked, based at least in part on at least one confidence score associated with the at least one of the plurality of surface types.

7. The apparatus of claim 5, wherein the at least one surface signature comprises first and second surface signatures, and where in C), the at least one processor:

C3) identifies, based at least in part on the first surface signature and the reference data, a first surface type of the plurality of surface types as possibly matching the surface to be marked, the first surface type being associated with a first confidence score;

C4) identifies, based at least in part on the second surface signature and the reference data, a second surface type of the plurality of surface types as possibly matching the surface to be marked, the second surface type being associated with a second confidence score; and

C5) identifies one of the first and second surface types as a candidate surface type for the surface to be marked, based at least in part on the first and second confidence scores.

8. The apparatus of claim 7, wherein the sensor data comprises first sensor data collected by at least a first sensor and second sensor data collected by at least a second sensor, and wherein the first surface signature is determined based at least in part on the first sensor data and the second surface signature is determined based at least in part on the second sensor data.

9. The apparatus of claim 2, wherein the one or more sensors comprise at least one camera and the sensor data comprises image data representing at least one image of the surface to be marked captured by the camera.

10. The apparatus of claim 9, wherein in C1), the at least one processor:

C2) determines a surface signature associated with the surface to be marked, based at least in part on a luminance distribution associated with the image data; and

C3) compares the surface signature with a plurality of reference signatures in the reference data to identify the candidate surface type, wherein each reference signature is indicative of a characteristic luminance distribution for at least one corresponding surface type in the plurality of surface types.

11. The apparatus of claim 9, wherein in C1), the at least one processor:

C2) determines a surface signature associated with the surface to be marked, based at least in part on color information associated with the image data; and

C3) compares the surface signature with a plurality of reference signatures in the reference data to identify the candidate surface type, wherein each reference signature is indicative of a color characteristic for at least one corresponding surface type in the plurality of surface types.

12. The apparatus of claim 11, wherein the color information associated with the image data comprises a spatial distribution of color in the at least one image.

13. The apparatus of claim 11, wherein the color information associated with the image data comprises a most prevalent color in the at least one image.

14. The apparatus of claim 11, wherein the color information associated with the image data comprises an average color in the at least one image.

15. The apparatus of claim 9, wherein in C1), the at least one processor:

C2) determines a surface signature associated with the surface to be marked, based at least in part on an entropy value derived based on the image data; and

C3) compares the surface signature with a plurality of reference signatures in the reference data to identify the candidate surface type, wherein each reference signature is indicative of a characteristic entropy value for at least one corresponding surface type in the plurality of surface types.

16. The apparatus of claim 15, wherein the entropy value is derived based at least in part on intensity information in the image data.

17. The apparatus of claim 15, wherein the entropy value is derived based at least in part on color information in the image data.

18. The apparatus of claim 9, wherein in C1), the at least one processor:

C2) determines a surface signature associated with the surface to be marked, based at least in part on a frequency at which edges are detected in the at least one image; and

C3) compares the surface signature with a plurality of reference signatures in the reference data to identify the candidate surface type, wherein each reference signature is indicative of a characteristic frequency of edges for at least one corresponding surface type in the plurality of surface types.

19. The apparatus of claim 9, wherein in C1), the at least one processor:

C2) determines a surface signature associated with the surface to be marked, based at least in part on a presence or absence of one or more line patterns in the at least one image; and

C3) compares the surface signature with a plurality of reference signatures in the reference data to identify the candidate surface type, wherein each reference signature is indicative of one or more characteristic line patterns for at least one corresponding surface type in the plurality of surface types.

20. The apparatus of claim 9, wherein in C1), the at least one processor:

C2) determines a first surface signature associated with the surface to be marked, based at least in part on a first portion of the at least one image;

C3) compares the first surface signature with a first plurality of reference signatures in the reference data to identify a first surface type as possibly matching the first portion of the at least one image;

C4) determines a second surface signature associated with the surface to be marked, based at least in part on a second portion of the at least one image;

C5) compares the second surface signature with a second plurality of reference signatures in the reference data to identify a second surface type as possibly matching the second portion of the at least one image; and

C6) determines whether the first surface type is different from the second surface type.

21. The apparatus of claim 9, wherein in C1), the at least one processor:

C2) determines a surface compression ratio associated with the surface to be marked, at least in part by performing a compression operation on at least a portion of the image data; and

C3) compares the surface compression ratio with a plurality of reference compression ratios in the reference data to identify the candidate surface type, wherein each reference compression ratio is associated with at least one corresponding surface type in the plurality of surface types.

22. The apparatus of claim 2, wherein the one or more sensors comprise an IR sensor and the sensor data comprises at least one temperature measurement of the surface to be marked taken by the IR sensor, and wherein in C1), the at least one processor:

C2) compares the at least one temperature measurement with a plurality of reference temperatures in the reference data to identify the candidate surface type, wherein each reference temperature is associated with at least one corresponding surface type in the plurality of surface types.

23. The apparatus of claim 22, wherein the one or more sensors further comprise an ambient temperature sensor and an ambient light sensor, and the sensor data further comprises an ambient temperature level and an ambient light level measured respectively by the temperature sensor and an ambient light sensor, and wherein the plurality of reference temperatures are selected based at least in part on the ambient temperature level and the ambient light level.

24. The apparatus of claim 2, wherein the one or more sensors comprises at least one radiation sensor capable of detecting electromagnetic radiation in at least one frequency band, and wherein in C1), the at least one processor:

C2) determines, based at least in part on the sensor data, a surface spectral signature associated with the surface to be marked; and

C3) compares the surface spectral signature with a plurality of reference spectral signatures in the reference data to identify the candidate surface type, wherein each reference spectral signature is associated with at least one corresponding surface type in the plurality of surface types.

25. In a system comprising at least one communication interface, at least one memory to store processor-executable instructions, and at least one processor communicatively coupled to the at least one memory and the at least one communication interface, a method for determining a surface type of a surface on which marking material is to be dispensed by a marking device to mark a presence or an absence of at least one underground facility within a dig area, wherein at least a portion of the dig area is planned to be excavated or disturbed during excavation activities, the method comprising acts of:

A) obtaining sensor data relating to the surface to be marked, the sensor data being collected by one or more sensors attached to the marking device;

B) retrieving, from the at least one memory, reference data associated with a plurality of surface types; and

C) using the at least one processor to generate surface type information based at least in part on the sensor data and the reference data.

26. At least one non-transitory computer-readable storage medium encoded with at least one program including processor-executable instructions that, when executed by at least one processor, perform a method for determining a surface type of a surface on which marking material is to be dispensed by a marking device to mark a presence or an absence of at least one underground facility within a dig area, wherein at least a portion of the dig area is planned to be excavated or disturbed during excavation activities, the method comprising acts of:

A) obtaining sensor data relating to the surface to be marked, the sensor data being collected by one or more sensors attached to the marking device;

B) retrieving, from at least one memory, reference data associated with a plurality of surface types; and

C) generating surface type information based at least in part on the sensor data and the reference data.

27. A marking apparatus for performing a marking operation to mark on a surface a presence or an absence of at least one underground facility, the marking apparatus comprising:

at least one actuator to dispense a marking material so as to form at least one locate mark on the surface to mark the presence or the absence of the at least one underground facility;

at least one sensor for sensing the surface to be marked;

at least one user interface including at least one display device;

at least one communication interface;

at least one memory to store processor-executable instructions; and

at least one processor communicatively coupled to the at least one memory, the at least one communication interface, the at least one user interface, and the at least one actuator, wherein upon execution of the processor-executable instructions, the at least one processor;

A) obtains sensor data relating to the surface to be marked, the sensor data being collected by the at least one sensor;

B) retrieves, from the at least one memory, reference data associated with a plurality of surface types; and

C) generates surface type information based at least in part on the sensor data and the reference data.