OBSCURED FEATURE DETECTOR WITH BUILT-IN CORRECTION MODULE

• US 20110215819A1
• Filed: 03/03/2011
• Published: 09/08/2011
• Est. Priority Date: 03/04/2010
• Status: Active Grant

• Current Assignee: Franklin Sensors Inc.
• Original Assignee: Franklin Sensors Inc.
• Inventors: Dorrough, David M.
• Granted Patent: US 8,836,347 B2
• Time in Patent Office: Days
• US Class Current: 324/684
• CPC Class Codes: G01N 27/22 by investigating capacitance
• CPC Class Codes: G01N 27/221 by investigating the dielectric properties using microwaves G01N22/00; measuring loss factors or dielectric constants per se G01R27/26
• CPC Class Codes: G01R 27/26 Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
• CPC Class Codes: G01R 27/2605 Measuring capacitance capacitive sensors G01D5/24
• 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 3/15 specially adapted for use during transport, e.g. by a person, vehicle or boat

Abstract

A surface-conforming obscured feature detector includes a plurality of sensor plates, each having a capacitance that varies based on the dielectric constant of the materials that compose the surrounding objects and the proximity of those objects. A sensing circuit is coupled to the sensor plates 32 to measure the capacitances of the sensor plates. A controller is coupled to the sensing circuit to analyze the capacitances measured by the sensing circuit. One or a plurality of indicators are coupled to the controller, and are selectively activated to identify the location of an obscured feature behind a surface.

Claims

1-181. -181. (canceled)

182. An obscured feature detector comprising:

a plurality of sensor plates, each having a capacitance that varies based on;

(a) the proximity of the sensor plates to one or more surrounding objects, and (b) the dielectric constant(s) of the surrounding object(s);

a sensing circuit coupled to the sensor plates, the sensing circuit being configured to measure the capacitance of each of the sensor plates;

a controller coupled to the sensing circuit, the controller being configured to analyze the capacitances measured by the sensing circuit;

a surface material detection module coupled to the controller and configured to detect one or more properties of a detected surface; and

a correction module coupled to the controller and configured to apply corrections to the measured capacitances using at least one of the properties detected by the surface detection module.

183. The obscured feature detector of claim 182, wherein the detected surface property is the surface'"'"'s dielectric constant.

184. The obscured feature detector of claim 182, wherein the detected surface property is the surface'"'"'s thickness.

185. The obscured feature detector of claim 182, wherein the detected surface property is an estimation based on at least the surface'"'"'s thickness and dielectric constant.

186. The obscured feature detector of claim 182, wherein the surface material detection module uses the smallest measured capacitance from the plurality of capacitances measured on the sensor plates to estimate a property of the surface material.

187. The obscured feature detector of claim 182, wherein the surface material detection module measures the capacitance between two sensor plates to estimate a property of the surface material.

188. The obscured feature detector of claim 182, wherein an estimate of a property of the surface is multiplied by a correction factor(s) to create an adjustment value(s), the adjustment value(s) is then added to, or subtracted from, the measured capacitance(s) to correct the capacitance reading(s).

189. The obscured feature detector of claim 188, wherein a first correction factor is applied to correct a capacitance measurement from a sensor plate that is near the edge of the detector, and a second correction factor is applied to correct a capacitance reading from location sensor plate that is near the center of the detector.

190. The obscured feature detector of claim 182 further comprising:

one or a plurality of indicators coupled to the controller, each indicator capable of toggling between a deactivated state and an activated state, and

wherein the controller is configured to activate one or more of the indicators to identify a location of an obscured feature

191. The obscured feature detector of claim 182, wherein the surface material detection module compares capacitance readings that are derived from two distinct plate activation patterns to estimate a property of the detected surface.

192. The obscured feature detector of claim 191, wherein a pattern of plate activation configurations comprises a set of sensor plates that are floating.

193. A method for determining the location of an obscured feature behind a surface, the method comprising:

placing an obscured feature detector on the surface, the obscured feature detector having a plurality of sensor plates arranged in an array;

measuring capacitance readings in an area surrounding one or more of the sensor plates;

detecting at least one property of the surface;

correcting the capacitance readings, using the detected property of the surface;

identifying, based upon the corrected capacitance readings, the location of one or a plurality of obscured features; and

activating one or a plurality of indicators to identify the location of an obscured feature.

194. The method of claim 193, wherein the step of correcting the capacitance readings uses the surface'"'"'s detected dielectric constant.

195. The method of claim 193, wherein the step of correcting the capacitance readings uses the surface'"'"'s detected thickness.

196. The method of claim 193, wherein the step of correcting the capacitance readings uses a detected correction factor comprising the surface'"'"'s thickness and dielectric constant.

197. The method claim 193, wherein detecting a property of the surface comprises using the one or more plates'"'"' smallest capacitance reading.

198. The method claim 193, wherein detecting a property of the surface comprises reading the capacitance between two sensor plates.

199. The method of claim 193, wherein correcting the capacitance readings comprises:

multiplying the surface property by a correction factor, the product being an adjustment value; and

adding or subtracting the adjustment value from the measured capacitances to correct the readings.

200. The method of claim 199, wherein correcting the capacitance readings comprises:

applying a first correction factor to correct a capacitance reading from a location that is near the edge of the detector, and

applying a second correction factor to correct a capacitance reading from a location that is near the center of the detector.

201. The method of claim 193, wherein detecting a surface property comprises comparing readings from two different plate activation patterns to create an estimate of a surface property.

202. The method of claim 201, wherein detecting a surface property comprises reading the sensor plates with a plate activation pattern comprising a set of sensor plates that are read.

203. The method of claim 202, wherein detecting a surface property comprises reading the sensor plates with a plate activation pattern comprising a set of sensor plates that are left floating.

204-239. -239. (canceled)