Multi-frequency locating system and methods

• US 9,927,545 B2
• Filed: 11/14/2012
• Issued: 03/27/2018
• Est. Priority Date: 11/14/2011
• Status: Active Grant

• Current Assignee: Seescan, Inc.
• Original Assignee: Seescan, Inc.
• Inventors: Olsson, Mark S., Cox, David A., Bench, Stephanie M., Soukup, Jan, Turner, Timothy M., Levin, Ryan B., Merewether, Ray
• Primary Examiner(s): Le, Son
• Assistant Examiner(s): DICKINSON, DUSTIN R
• Application Number:
  US13/677,223
• Publication Number:
  US 20140132269A1
• Time in Patent Office: 1,959 Days
• Field of Search: 324 66- 67, 324326-329
• CPC Class Codes: G01V 3/08 operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices with electromagnetic waves G01V3/12
• CPC Class Codes: G01V 3/10 using induction coils
• CPC Class Codes: G01V 3/15 specially adapted for use during transport, e.g. by a person, vehicle or boat

Abstract

Multi-frequency buried object location system transmitters and locators are disclosed. A transmitter may generate and provide output signals to a buried object at a plurality of frequencies, which may be selected based on a connection type. Corresponding locators may simultaneously receive a plurality of magnetic field signals emitted from the buried object and generate visual and/or audible output information based at least in part on the plurality of received magnetic field signals. The visual and/or audible output may be further based on signals received from a quad-gradient antenna array.

Claims

1. A multi-frequency buried object locating system, comprising:

a buried object transmitter to simultaneously generate and provide a plurality of output current signals, phased locked to one another at different frequencies, to a buried object; and

a buried object locator comprising;

a mast;

an omnidirectional antenna array disposed on or coupled to the mast, the omnidirectional antenna array including three nested coils positioned orthogonally to each other to sense radiated signal components associated with magnetic fields emitted from a buried object in three orthogonal dimensions at different frequencies, wherein the magnetic fields are generated at the buried object based on the output current signals from the buried object transmitter;

a housing coupled to the mast;

a display element disposed on or within the housing; and

a processing element disposed in the housing;

wherein the processing element is configured to simultaneously receive and process the radiated signal components in three orthogonal dimensions at different frequencies and generate, based on two or more of the simultaneously received and processed radiated signal components, information associated with the buried object, including at least a determined depth measurement of the buried object, for rendering of the determined information on the display element.

2. The locating system of claim 1, wherein the display information includes a plurality of lines representing positions of the utility determined based on the plurality of magnetic field signals emitted from the buried object at different frequencies.

3. The locating system of claim 1, wherein the display information includes distortion information associated with estimates of the position of the buried object based on two or more of the plurality of magnetic field signals.

4. The locating system of claim 1, wherein the estimate of the position of the buried object is displayed as object, and the object is blurred as a function of a determined distortion of the position estimate.

5. The locating system of claim 4, wherein the buried object is a line and the line is blurred as a function of the determined distortion of the position estimate.

6. The locating system of claim 1, wherein a first of the plurality of radiated signal components is received at a predefined unique frequency associated with a connection type, and wherein the first of the plurality of radiated signal components is processed to determine the display information associated with the buried object based on the connection type.

7. The locating system of claim 6, wherein a second of the plurality of radiated signal components is received at a second predefined unique frequency associated with a second connection type, and wherein the second of the plurality of radiated signal components is processed to determine the display information associated with the buried object based on the second connection type.

8. The locating system of claim 1, wherein a first of the plurality of radiated signal components is received at a first predefined unique frequency associated with a connection type and a second of the plurality of radiated signal components is simultaneously received at a second predefined unique frequency associated with the connection type, wherein the display information associated with the buried object is based on both the first of the plurality of radiated signal components and the second of the plurality of radiated signal components.

9. The locating system of claim 1, wherein a first of the plurality of radiated signal components is received at a first predefined unique frequency associated with a first connection type and a second of the plurality of radiated signal components is simultaneously received at a second predefined unique frequency associated with a second connection type, wherein the display information associated with the buried object is based on both the first of the plurality of radiated signal components and the second of the plurality of radiated signal components.

10. The locating system of claim 1, wherein the processing element is further configured to generate the display information associated with the buried object based on radiated signal components received from a quad gradient antenna array.

11. The locator of claim 1, wherein the determined information further includes an estimated position of the buried object on the ground surface.

12. A method for use in a buried object locator system, comprising:

simultaneously generating, at a buried object transmitter, a plurality of output signals at ones of a plurality of different output frequencies, wherein the plurality of output signals are phase locked to each other;

coupling the phased locked output signals from the transmitter to a buried object in the ground to generate a buried object current corresponding to the output signal components;

receiving, at a buried object locator, including omnidirectional antenna array including three nested coils positioned orthogonally to each other to sense magnetic field components at a point in space in three orthogonal axes, a plurality of radiated magnetic field signals associated with the buried object current at a plurality of the different output frequencies in three orthogonal dimensions; and

simultaneously determining, at the buried object locator, information associated with the buried object based on two or more of the radiated magnetic field signal components.

13. The method of claim 12, wherein the plurality of output signals are of the same connection type.

14. The method of claim 12, wherein the information associated with the buried object includes one or both of an estimate depth of the buried object and an estimated position of the buried object on the ground surface.

15. A buried object location system, comprising:

a buried object transmitter comprising;

a transmitter housing;

a timing synchronization module disposed in the transmitter housing to generate a timing reference signal;

a signal generation module disposed in the transmitter housing to simultaneously generate a plurality of phase synchronized output signal components at ones of a plurality of different output frequencies, wherein the output signals are phase synchronized based at least in part on the timing reference signal; and

a transmitting antenna disposed in the transmitter housing and coupled to the signal generation module, the transmitting antenna including one or more antenna coils to transmit the one or more output signal components to a buried object in the ground to generate a buried object current; and

a buried object locator including an antenna array having an omnidirectional antenna array for receiving magnetic field signals in three orthogonal dimensions resulting from the buried objection current, and a receiver to;

simultaneously receive and process radiated signal components associated with the buried object current at a plurality of the different output frequencies in three orthogonal dimensions; and

determine, at the buried object locator, information, including a determined depth, associated with the buried object based on two or more of the simultaneously received and processed radiated signal components.

16. The location system of claim 15, wherein the information further includes an estimated position of the buried object on the ground surface based on the two or more of the simultaneously received and processed radiated signal components.