System and method for detecting and locating underground objects

• US 6,825,793 B2
• Filed: 02/26/2003
• Issued: 11/30/2004
• Est. Priority Date: 03/01/2002
• Status: Active Grant

• Current Assignee: ENSCO, Incorporated (Teris LLC)
• Original Assignee: ENSCO, Incorporated (Teris LLC)
• Inventors: Taylor, David W. A. Jr., Bell, Alan G. R.
• Primary Examiner(s): Gregory, Bernarr E.
• Assistant Examiner(s): ANDREA, BRIAN K
• Application Number:
  US10/373,095
• Publication Number:
  US 20030164789A1
• Time in Patent Office: 643 Days
• Field of Search: 342/22, 342/27, 324/337, 324/326, 324/329
• US Class Current: 342/22
• CPC Class Codes: G01S 13/88 Radar or analogous systems specially adapted for specific applications electromagnetic prospecting or detecting of objects, e.g. near-field detection, G01V3/00
• CPC Class Codes: G01S 13/885 for ground probing prospecting or detecting using electromagnetic waves G01V3/12
• CPC Class Codes: G01V 3/12 operating with electromagnetic waves operating with millimetre waves G01V8/005

Abstract

A system for detecting and locating an underground object having stationary RF transmitter receivers that define a coordinate system for an area of interest, a sensor adapted to detect presence of an underground object and to provide a presence data, and a mobile RF transmitter receiver that is movable with the sensor, and is adapted to receive and/or transmit location data indicative of location of the mobile transmitter receiver in the coordinate system. A method is also provided for detecting and locating underground object including the steps of establishing a coordinate system for an area of interest, detecting presence of an underground object and providing a presence data upon detection of the underground object, and transmitting and/or receiving location data in a radio frequency, the location data being indicative of location of the underground object in the established coordinate system.

Claims

1. A system for detecting and locating an underground object comprising:

a plurality of stationary transmitter receivers operating in a radio frequency, said plurality of stationary transmitter receivers defining a relative coordinate system for an area of interest;

a sensor adapted to detect an underground object and to provide a presence data upon detection of said underground object;

a mobile transmitter receiver operating in a radio frequency, said mobile transmitter receiver being movable with said sensor, and adapted to at least one of receive location data from and transmit location data to at least one of said plurality of stationary transmitter receivers, said location data being indicative of location of said mobile transmitter receiver in said relative coordinate system; and

a global positioning system (GPS) receiver adapted to fix said relative coordinate system defined by said plurality of stationary transmitter receivers to an absolute global position.

2. The system of claim 1, further comprising a data logger adapted to record at least one of said presence data and said location data.

3. The system of claim 2, wherein said data logger is integral with said mobile transmitter receiver.

4. The system of claim 1, wherein said location data is indicative of distance between said mobile transmitter receiver and at least one of said plurality of stationary transmitter receivers.

5. The system of claim 1, further comprising a processor unit adapted to process at least one of said presence data and said location data.

6. The system of claim 5, wherein said processor unit is adapted to process said location data to generate a mapping of said underground object in said relative coordinate system.

7. The system of claim 6, wherein said processor unit includes a display device for displaying said generated mapping of said underground object.

8. The system of claim 5, wherein said processor unit is further adapted to store at least one of said presence data and said location data.

9. The system of claim 5, wherein said processor unit is connected to at least one of said mobile transmitter receiver and one of said plurality of stationary transmitter receivers.

10. The system of claim 5, wherein said processor unit is a hand held computer.

11. The system of claim 1, wherein said underground sensor is at least one of an electromagnetic, magnetic, radio frequency, radiation, metal, and chemical detection sensor.

12. The system of claim 1, wherein said radio frequency is in a range between 900 MHz to 5.8 GHz.

13. The system of claim 1, wherein said mobile transmitter receiver includes a radio circuit having a data processing circuit adapted to determine propagation times of said location data.

14. The system of claim 13, wherein said data processing circuit is further adapted to determine distance between said mobile transmitter receiver and said at least one of said plurality of stationary transmitter receivers based on said propagation times.

15. The system of claim 1, wherein said mobile transmitter receiver includes at least one battery for providing portable power to said mobile transmitter receiver.

16. The system of claim 1, wherein at least one of said stationary transmitter receivers includes a spread spectrum radio circuit having a data processing circuit adapted to determine propagation times of said location data.

17. The system of claim 16, wherein said data processing circuit is further adapted to determine distance between said at least one of said plurality of stationary transmitter receivers and said mobile transmitter receiver based on said propagation times.

18. The system of claim 1, wherein said underground object is at least one of gas, electric, telephone, fiber optics, cable, water, and sewage utility.

19. A method for detecting and locating underground object comprising the steps of:

establishing a relative coordinate system for an area of interest;

detecting an underground object and providing a presence data upon detection of said underground object;

at least one of transmitting and receiving location data in a radio frequency, said location data being indicative of location of said underground object in said established relative coordinate system;

receiving a global position system (GPS) signal indicative of an absolute global position; and

fixing said relative coordinate system to said absolute global position to establish a fixed coordinate system.

20. The method of claim 19, wherein said step of establishing a relative coordinate system includes the step of arranging a plurality of stationary transmitter receivers operating in a radio frequency proximate to said area of interest.

21. The method of claim 20, wherein said step of fixing said relative coordinate system is attained by determining global position of at least one of said plurality of stationary transmitter receivers.

22. The method of claim 20, wherein said underground object is detected using a sensor.

23. The method of claim 22, wherein said underground sensor is at least one of an electromagnetic, magnetic, and radio detection sensor.

24. The method of claim 20, further including the step of moving a mobile transmitter receiver to the location where said underground object is detected.

25. The method of claim 24, wherein said location data is indicative of distance between said mobile transmitter receiver and at least one of said plurality of stationary transmitter receivers.

26. The method of claim 24, further including the steps of determining propagation times of said location data, and determining distance between at least one of said plurality of stationary transmitter receivers and said mobile transmitter receiver based on said propagation times.

27. The method of claim 20, further comprising the step of processing at least one of said presence data and said location data to generate a mapping of said underground object in said relative coordinate system.

28. The method of claim 27, further comprising the step of displaying said generated mapping of the underground object.

29. The method of claim 20, further including the step of moving said plurality of stationary transmitter receivers to an adjacent area that is adjacent to said area of interest and establishing an adjacent relative coordinate system for said adjacent area.

30. The method of claim 29, further including the steps of detecting an adjacent underground object in said adjacent area and providing adjacent presence data upon detection of said adjacent underground object.

31. The method of claim 30, further including the step of at least one of transmitting and receiving adjacent location data in a radio frequency, said adjacent location data being indicative of location of said adjacent underground object in said established adjacent coordinate system.

32. The method of claim 19, further including the step of recording at least one of said presence data and said location data.

33. The method of claim 19, wherein said radio frequency is in a range between 900 MHz to 5.8 GHz.

34. The method of claim 19, wherein said underground object is at least one of gas, electric, telephone, fiber optics, cable, water, and sewage utility.