Method and apparatus for detecting, mapping and locating underground utilities

• US 20020130806A1
• Filed: 03/12/2002
• Published: 09/19/2002
• Est. Priority Date: 03/12/2001
• Status: Active Grant

• Current Assignee: ENSCO, Incorporated (Teris LLC)
• Original Assignee: ENSCO, Incorporated (Teris LLC)
• Inventors: McBride, William H.A., Bell, Alan G.R., Taylor, David W.A. Jr., Roland, John S., Fields, George R.A., Faulkner, William T., McGarvey, Matthew W., Rosenberg, Yuri
• Granted Patent: US 6,999,021 B2
• Time in Patent Office: Days
• US Class Current: 342/22
• CPC Class Codes: G01S 13/885 for ground probing prospecting or detecting using electromagnetic waves G01V3/12
• CPC Class Codes: G01S 13/89 for mapping or imaging
• CPC Class Codes: G01V 3/15 specially adapted for use during transport, e.g. by a person, vehicle or boat

Abstract

The method and device for locating underground utilities within an area includes traversing the area with a plurality of underground utility sensors and obtaining area location data to locate the area traversed. The sensor data and area location data are used to map the location of one or more utilities within the area traversed.

Claims

1. A method for locating underground utilities within an area of interest which includes:

traversing back and forth across said area of interest with a plurality of underground utility sensors to cover the area of interest,

obtaining sensor data from each of said plurality of underground utility sensors while traversing said area of interest,

obtaining area location data from a position locating system while traversing said area of interest to obtain area location data indicative of the location of the area of interest traversed, and

using said sensor data and area location data to map the location of one or more underground utilities within said area of interest.

2. The method of claim 1 which includes using the sensor data from each of said plurality of underground utility sensors with said area location data to create a separate map.

3. The method of claim 2 which includes obtaining sensor data from each of a plurality of different underground utility sensors having different modes of operation.

4. The method of claim 1 which includes using a plurality of wideband electromagnetic field sensors to obtain sensor data having multiple frequencies from said wideband electromagnetic field sensors.

5. The method of claim 4 which includes separating the frequencies in the sensor data having multiple frequencies for each wideband electromagnetic field sensor into separate frequency related sensor data outputs.

6. The method of claim 1 which includes:

beamforming the sensor data to a suite of angles which cover all possible orientations of the underground utility to determine which orientation contains sensor data which indicates the presence of a linear feature; and

integrating the location data with the data that corresponds to the linear feature to determine the location of the underground utility.

7. The method of claim 6 which includes locating peaks in the sensor data which represent anomalies and beamforming the peaks to a suite of angles and determining which orientation includes the highest number of peaks as an indication of a linear feature.

8. The method of claim 7 which includes comparing said located peaks with a predetermined threshold value and selecting the peaks which exceed said predetermined threshold value for beamforming to said suite of angles.

9. The method of claim 8 which includes rank ordering all sensor data in a data set by value;

removing from the data set a predefined percentage of the largest and smallest values of the ranked sensor data in the data set; and

computing the mean and standard deviation of the remaining values in the ranked sensor data in the data set before comparing the peaks with said predetermined threshold value.

10. The method of claim 9 wherein said predetermined threshold value is equal to a constant * standard deviation+mean.

11. The method of claim 10 wherein said constant is 1.0 to 3.0 in value.

13. The method of claim 12 which includes locating peaks in the sensor data which represent anomalies and beamforming the peaks to a suite of angles and determining which orientation includes the highest number of peaks as an indication of a linear feature.

14. The method of claim 13 which includes comparing said located peaks with a predetermined threshold value and selecting the peaks which exceed said predetermined threshold value for beamforming to said suite of angles.

15. The method of claim 12 which includes traversing said area of interest with said position locating system and said underground utility sensors and obtaining a plurality of sequential data sets, each of which includes location data and sensor data,

beamforming the sensor data from each data set to said suite of angles to determine which orientation contains sensor data which indicates the presence of a linear feature;

and

integrating the location data for each data set with data for said data set that corresponds to the linear feature to determine the location of the portion of the underground utility within the area from which said data set was obtained.

16. The method of claim 15 which includes locating peaks in the sensor data for each data set which represent anomalies and beamforming the peaks located in each data set to a suite of angles;

and

determining which orientation includes the highest number of peaks as an indication of a linear feature.

17. The method of claim 16 which includes comparing said located peaks with a predetermined threshold value and selecting the peaks which exceed said predetermined threshold value for beamforming to said suite of angles.

18. The method of claim 17 which includes rank ordering all sensor data in a data set by value;

removing from the data set a predefined percentage of the largest and smallest values of the ranked sensor data in the data set; and

computing the mean and standard deviation of the remaining values in the ranked sensor data in the data set before comparing the peaks with said predetermined threshold value.

19. The method of claim 18 wherein said predetermined threshold value is equal to a constant*standard deviation+mean.

20. The method of claim 19 wherein said constant is 1.0 to 3.0 in value.

12. A method for detecting underground utilities within an area of interest which includes:

obtaining area location data from a position locating system to identify the location of said area of interest,

obtaining sensor data from said area of interest using a plurality of different underground utility sensors;

beamforming the sensor data to a suite of angles which cover all possible orientation of a sensed underground utility to determine which orientation contains sensor data which indicates the presence of a linear feature; and

mapping the sensor data indicative of the presence of a linear feature.

21. A device for locating underground utilities within an area of interest comprising:

a movable multisensor unit for detecting underground utilities within the area of interest, said movable multisensor unit including a base, at least two different underground utility sensing units having different modes of operation mounted on said base to provide separate data outputs when said sensing units sense underground utilities during movement of said base over said area of interest, and a position locating receiver mounted on said base for receiving positional data relating to the position of the area of interest over which said base is moved, and

a mapping unit to receive positional data from said position locating receiver and the data outputs from said underground utility sensing units, said mapping unit operating in response to said positional data to map said area of interest and in response the data outputs from said underground utility sensing units to map data signals indicative of the location of underground utilities within said area of interest.

22. The device of claim 21 wherein said movable multisensor unit includes a cable locator with three or more wideband electromagnetic field sensors with at least one sensor oriented vertically, one sensor oriented horizontally and one sensor oriented orthogonal to said vertically and horizontally oriented sensors, each sensor operating to receive multiple frequencies from an underground utility and to provide a data output which includes one or more of said multiple frequencies.

23. The device of claim 22 wherein said cable locator includes frequency separator means operative to receive the multiple frequencies in the data output from each of said wideband electromagnetic field sensors and to separate each frequency into a single frequency output.

24. The device of claim 21 wherein said movable multisensor unit includes a cable locator with two or more magnetic coil sensors, each sensor operating to receive multiple frequencies from an underground utility and to provide a data output which includes one or more of said multiple frequencies.

25. The device of claim 24 wherein said cable locator includes frequency separator means operative to receive the multiple frequencies in the data output from each of said magnetic coil sensors and to separate each frequency into a single frequency output.

27. The device of claim 26 which includes a plurality of narrowband RF transmitters located in said area of interest, each of said RF transmitters transmitting a different narrowband frequency.

29. The device of claim 28 which includes a plurality of narrowband RF transmitters located in said area of interest, each of said RF transmitters transmitting a different narrowband frequency.

26. A device for locating underground utilities within an area of interest comprising:

a movable multisensor unit for detecting underground utilities within the area of interest;

said movable multisensor unit including a cable locator including three or more wideband electromagnetic field sensors with at least one sensor oriented vertically, one sensor oriented horizontally and one sensor oriented orthogonal to said vertically and horizontally oriented sensors, each sensor operating to receive multiple frequencies from an underground utility and to provide a data output which includes one or more of said multiple frequencies, and

frequency separator means operative to receive the multiple frequencies in the data output from each of said sensors and to separate each frequency into a single frequency output.

28. A device for locating underground utilities within an area of interest comprising:

a movable multisensor unit for detecting underground utilities within the area of interest;

said movable multisensor unit including a cable locator including two or more magnetic coil sensors, each sensor operating to receive multiple frequencies from an underground utility and to provide a data output which includes one or more of said multiple frequencies, and frequency separator means operative to receive the multiple frequencies in the data output from each of said sensors and to separate each frequency into a single frequency output.