Omnidirectional sonde and line locator

• US 7,009,399 B2
• Filed: 10/09/2002
• Issued: 03/07/2006
• Est. Priority Date: 10/09/2002
• Status: Active Grant

• Current Assignee: Seek Tech, Inc.
• Original Assignee: Deep Sea Power & Light Incorporated
• Inventors: Kolb, Thomas R., Barnicoat, Bradley D., Cox, David A., Merewether, Ray, Olsson, Mark S., Martin, Michael J., Hilton, Randall P.
• Primary Examiner(s): Lefkowitz, Edward
• Assistant Examiner(s): Aurora, Reena
• Application Number:
  US10/268,641
• Publication Number:
  US 20040070399A1
• Time in Patent Office: 1,245 Days
• Field of Search: 324/326, 324/329, 324333-334, 342/459
• US Class Current: 324/326
• CPC Class Codes: G01V 3/15 specially adapted for use during transport, e.g. by a person, vehicle or boat

Abstract

At least one antenna array including three mutually orthogonal antennas each sharing a common center point senses an electromagnetic signal emitted by a buried object such as a utility line, pipe or sonde. A circuit at least partially mounted in a housing is connected to the array and determines a location of the buried object by measuring signal strength and field angles in three dimensions without having to align the antenna array relative to the buried object while eliminating nulls and false peaks. A graphical user interface (GUI) has user-friendly icons, symbols, menus, numbers and graphical and auditory representation of signal strength. A SEARCH view indicates signal strength by showing a rotating strength indicator, a trace mode MAP view in which line location is shown by a line that moves side-to-side, and a sonde mode MAP view in which sonde location is shown by a moving line, pole and equator.

Claims

1. An omnidirectional manually portable system for locating a buried object by sensing an electromagnetic signal emitted by the buried object, comprising:

a housing;

at least one antenna array including three substantially mutually orthogonal antennas each sharing a common center point;

an elongate member having an end connected to the housing and supporting the antenna array, the elongate member having a central axis that extends through the common center point, and an angle subtended between the central axis and each of the antennas being substantially identical; and

circuit means at least partially mounted in the housing and connected to the antennas in the antenna array for sensing an electromagnetic signal emitted from a buried object and determining a location of the buried object by measuring signal strength and field angles in three dimensions.

2. The system of claim 1 wherein the circuit means senses an electromagnetic signal in a frequency range of approximately 50 Hz to 500 kHz.

3. The system of claim 1 wherein each of the three antennas has a circular configuration.

4. The system of claim 1 wherein the circuit means includes a display mounted in the housing and means for driving the display to provide a visual indication of the determined location of the buried object.

5. The system of claim 1 wherein the circuit means includes an audio transducer and means for driving the audio transducer to provide an audible indication of the determined location of the buried object.

6. The system of claim 1 and further comprising a fourth antenna spaced from the antenna array and connected to the circuit means for enabling the determination of a depth of the buried object.

7. The system of claim 1 and further comprising a second antenna array mounted to the elongate member and spaced from the one antenna array, the second antenna array also including three substantially mutually orthogonal antennas, and the second antenna array being connected to the circuit means for enabling the determination of a depth of the buried object.

8. An omnidirectional manually portable system for locating a buried object by sensing an electromagnetic signal emitted by the object, comprising:

a first antenna array including three substantially mutually orthogonal antennas in the form of a first plurality of coils sharing a first common center point;

a second antenna array including three substantially mutually orthogonal antennas in the form of a second plurality of coils sharing a second common center point;

a housing including a handle portion;

an elongate member connecting the first and second antenna arrays to the housing and having a central axis extending through the first and second common center points, the elongate member supporting the first and second antenna arrays in spaced apart relation, and an angle subtended between the central axis of the elongate member and each of the antennas being substantially identical; and

circuit means at least partially mounted in the housing and connected to the antennas in the first and second antenna arrays for sensing an electromagnetic signal having a frequency in a range of approximately 50 Hz to 500 kHz emitted by a buried object and determining a location and depth of the buried object by measuring signal strength and field angles in three dimensions utilizing the first and second antenna arrays, the circuit means including means for providing a visual and/or audible indication of the determined location and depth of the buried object.