ECONOMICAL MAGNETIC LOCATOR APPARATUS AND METHODS

• US 20150338539A1
• Filed: 06/08/2015
• Published: 11/26/2015
• Est. Priority Date: 03/04/2010
• Status: Active Grant

• Current Assignee: Seescan, Inc.
• Original Assignee: Seescan, Inc.
• Inventors: Olsson, Mark S., Merewether, Ray
• Granted Patent: US 9,632,202 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01B 7/003 for measuring position, not involving coordinate determination coordinate measuring G01B7/004
• CPC Class Codes: G01B 7/26 for measuring depth
• CPC Class Codes: G01R 33/096 anisotropic magnetoresistance sensors
• CPC Class Codes: G01R 33/10 Plotting field distribution ; Measuring field distribution
• 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 3/165 operating with magnetic or electric fields produced or modified by the object or by the detecting device with electromagnetic waves G01V3/17
• CPC Class Codes: G01V 3/38 Processing data, e.g. for analysis, for interpretation, for correction

Abstract

Magnetic locators for detection of buried objects, such as ferromagnetic objects, are disclosed. Outputs provided from two or more magnetic sensors, such as three three-axis magnetic sensors, as well as optionally from other sensors, such as accelerometers and gyroscopic sensors, may be used to determine magnetic field distortion indicative of ferromagnetic objects and/or provide output information corresponding to the detected objects based on the sensor outputs.

Claims

1. A magnetic locator, comprising:

a lower housing element;

a first three-axis magnetic sensor disposed on or within the lower housing element;

a second three-axis magnetic sensor positioned above the first three-axis magnetic sensor when the locator is positioned in a vertical orientation;

a circuit board module coupled to an output of the first three-axis magnetic sensor and the output of the second three-axis magnetic sensor for subtracting corresponding output signals from one of the three-axis magnetic sensors from output signals of the other of the three-axis magnetic sensor to determine at least in part a magnetic field distortion caused by a ferromagnetic object; and

an output element for providing an output associated with the ferromagnetic object.

2. The locator of claim 1, wherein the output element is a visual display.

3. The locator of claim 1, wherein the output element is an audible output device.

4. The locator of claim 1, wherein the housing element includes a tapered point.

5. The locator of claim 1, wherein the circuit board module is disposed on or within the lower housing element.

6. The locator of claim 1, wherein the second three-axis magnetic sensor is disposed on or within the lower housing element.

7. The locator of claim 1, further comprising an accelerometer having an output signal coupled to the circuit board module, wherein the output associated with the ferromagnetic object is further based in part on an output signal from the accelerometer.

8. The locator of claim 1, further comprising a gyroscopic sensor having an output signal coupled to the circuit board module, wherein the output associated with the ferromagnetic object is further based in part on an output signal from the gyroscopic sensor.

9. The locator of claim 1, further comprising a GPS receiver having an output signal coupled to the circuit board module, wherein the output associated with the ferromagnetic object is further based in part on an output signal from the GPS receiver.

10. The locator of claim 1, further comprising one or more additional three-axis magnetic sensors, for sensing magnetic fields in three axes at a compact point in space, having output signals coupled to the circuit board module, wherein the magnetic field distortion caused by the ferromagnetic object is further based on the output signals from the one or more additional three-axis magnetic sensors.

11. A magnetic locator, comprising:

a first sensor circuit for generating a first output signal corresponding to magnetic fields sensed in three orthogonal axes at a compact point in space from a magnetic sensor disposed in a locator housing element;

a second sensor circuit for generating a second output signal corresponding to magnetic fields sensed in three orthogonal axes at a compact point in space from a second three-axis magnetic sensor positioned above the first three-axis magnetic sensor when the locator is positioned in a vertical orientation;

a processing element for generating a signal corresponding to a magnetic field distortion caused by the object by subtracting corresponding first or second output signals from the other of the first or second output signals; and

an output device for providing an output corresponding to the object based in part on the magnetic field distortion.

12. A method of magnetically sensing an object with a magnetic locator, comprising:

generating a first output signal corresponding to magnetic fields sensed in three orthogonal axes at a compact point in space from a magnetic sensor disposed in a locator housing element;

generating a second output signal corresponding to magnetic fields sensed in three orthogonal axes at a compact point in space from a second three-axis magnetic sensor positioned above the first three-axis magnetic sensor when the locator is positioned in a vertical orientation;

generating a signal corresponding to a magnetic field distortion caused by the object by subtracting corresponding first or second output signals from the other of the first or second output signals; and

providing an output corresponding to the object based in part on the magnetic field distortion.